Co-reporter:Jing He, Peiwen Wu, Yingcheng Wu, Hongping Li, Wei Jiang, Suhang Xun, Ming Zhang, Wenshuai Zhu, and Huaming Li
ACS Sustainable Chemistry & Engineering October 2, 2017 Volume 5(Issue 10) pp:8930-8930
Publication Date(Web):August 13, 2017
DOI:10.1021/acssuschemeng.7b01741
Heterogeneous catalysis has become an important branch in the catalytic field, whereas catalytic activities of heterogeneous catalysts are controlled by surface features and structural textures. Herein, we reported a synthesis of an amphiphilic tungsten oxide catalyst with oxygen vacancies. Characterizations showed that oxygen vacancies had been successfully introduced in tungsten oxide by a solution etching process in an acidic condition. The process not only gave rise to oxygen vacancies but also maintained the excellent amphiphilic feature of the catalyst. Both advantages of the catalysts led to a 100% sulfur removal from fuel oil and a 15 times recycling performance without a significant decrease in activity. Additionally, the adsorption and catalytic oxidative desulfurization process was proposed and further studied by gas chromatography–mass spectrometry (GC–MS).Keywords: Amphiphilic; Heterogeneous catalyst; Oxidative desulfurization; Oxygen vacancies; Tungsten oxide;
Co-reporter:Zhigang Chen;Chao Wang;Wangqin Zhu;Peiwen Wu;Hongping Li;Ming Zhang;Wei Jiang;Wenshuai Zhu
Energy & Fuels February 16, 2017 Volume 31(Issue 2) pp:1376-1382
Publication Date(Web):January 9, 2017
DOI:10.1021/acs.energyfuels.6b02624
Four economic and easily prepared metal-based ionic liquids (MILs) were synthesized based on triethylamine hydrochloride (Et3NHCl) and a series of anhydrous metal chlorides (MClx). The stiochemistry of the as-prepared MILs is characterized systematically. Extraction and catalytic oxidative desulfurization (ECODS) of thiophenic sulfides is then achieved using the as-prepared MILs and molecular oxygen (O2) in air as the extractant and oxidant, respectively. The factors that could influence sulfur removal are investigated systematically, and deep desulfurization of oils with different S concentrations and substrates are achieved under optimized conditions simultaneously. Dibenzothiophene (DBT) removal reaches up to 99.4% under the optimized conditions. Sulfur removal with different sulfides decreases in the order of DBT > 4,6-dimethyldibenzothiophene (4,6-DMDBT) > benzothiophene (BT). The influence of the co-existence of alkenes and aromatics is also investigated. Moreover, the used amount of low-cost [Et3NH]FeCl4 is relatively low [V(MIL)/V(oil) = 1:15], and it could be recycled 5 times without a significant decrease in sulfur removal. Besides, it is verified that sulfur compounds are converted to their corresponding sulfones in the reaction process with the help of gas chromatography–mass spectrometry (GC–MS) measurement.
Co-reporter:Wei Jiang;Lei Dong;Wei Liu;Tao Guo;Hongping Li;Ming Zhang;Wenshuai Zhu
RSC Advances (2011-Present) 2017 vol. 7(Issue 87) pp:55318-55325
Publication Date(Web):2017/12/01
DOI:10.1039/C7RA10125B
Deep eutectic solvents (DESs) are ‘green’ sustainable solvents with wide applications such as extractive desulfurization of fuel; however, their low extraction efficiency is a major limitation to such applications. In this work, several SO3H-functionalized polyoxometalates were prepared and applied to oxidative desulfurization of fuels with acidic DESs as extractants and 30 wt% of H2O2 as an oxidant. Compared with neutral POM catalysts, acidic catalysts, such as [PSTEtA]3PW12O40, exhibited higher catalytic performance with 100% desulfurization efficiency. However, in the absence of DESs sulfur removal was only 9.6% with [PSTEtA]3PW12O40 used as a catalyst. To study the role of the DESs, three types of DESs were evaluated on extraction and oxidation of dibenzothiophene (DBT), with acidic DES ChCl/2Ac exhibiting the best performance. The effects of different reaction conditions, such as the amount of H2O2 and ChCl/2Ac, reaction temperature and time, different sulfur compounds, and fuel composition, were investigated. Combined with the kinetic study, results suggested that oxidation of DBT was attributed to a pseudo-first-order kinetic reaction. The activities of different sulfur compounds decreased in the order of DBT > 3-methylbenzothiophene (3-MBT) > 4-methyldibenzothiophene (4-MDBT) > 4,6-dimethyldibenzothiophene (4,6-DMDBT) > benzothiophene (BT). Compared with aromatics, the sulfur removal could be strongly affected by olefins, showing a drop of up to 66.6%.
Co-reporter:Xingwang Zhu;Jinyuan Liu;Zhenzhen Zhao;Jia Yan;Yuanguo Xu;Yanhua Song;Haiyan Ji;Hui Xu
RSC Advances (2011-Present) 2017 vol. 7(Issue 61) pp:38682-38690
Publication Date(Web):2017/08/02
DOI:10.1039/C7RA06681C
To overcome the shortcomings of low photocatalytic efficiency, mpg-C3N4/Bi2WO6 photocatalysts have been successfully designed via a facile hydrothermal method. A succession of techniques was used to explore the morphology, structure, surface composition and photocatalytic property of the mpg-C3N4/Bi2WO6 material. The mpg-C3N4/Bi2WO6 nanohybrid has high photocatalytic performance for the degradation of tetracycline hydrochloride (TC) and rhodamine B (RhB). Holes, ·O2− and ·OH radicals are determined to be the active species in the process of photocatalytic degradation by ESR and capture experiments. The ultrathin thickness of nest-like Bi2WO6 and the introduction of mpg-C3N4 into the Bi2WO6 matrix can improve the photocatalytic efficiency. The photocatalytic Z-scheme mechanism of the system was also discussed in detail. This work paves the way for preparing visible-light-driven nanocomposites for pollutant degradation.
Co-reporter:Jia Yan;Jiemin Gu;Xin Wang;Yamin Fan;Yan Zhao;Jiabiao Lian;Yuanguo Xu;Yanhua Song;Hui Xu
RSC Advances (2011-Present) 2017 vol. 7(Issue 40) pp:25160-25170
Publication Date(Web):2017/05/05
DOI:10.1039/C7RA02929B
3D WO3 nanoparticle/h-BN nanosheet composites (WO3/BN) have been designed and fabricated by a simple in situ one-step calcination method. By homogeneous dispersing WO3 on graphene-like BN nanosheets, the as-fabricated WO3/BN nanocomposites provided large surface area with more active sites, and a significant red shift of absorption edge from 310 nm to 800 nm containing the full visible optical spectrum absorption was realized, which was favorable for enhancing the absorption of the visible light area and taking full advantages of visible light utilization. Subsequently, the as-fabricated nanocomposites were employed for photocatalytic study under visible light illumination, and the 20% WO3/BN sample exhibited the highest photocatalytic activity for Rhodamine B (RhB) degradation with the degradation efficiency of ∼92%. Additionally, the WO3/BN nanocomposites have the excellent degradation efficiency toward Ciprofloxacin (CIP) that was hard to be degradation under visible light illumination, which could be ascribed to the homodisperse WO3 with more effective active sites for the target pollutants and a synergistic effect between the WO3 and graphene-like BN. ESR and the radical trapping experiments were further conducted to study the degradation mechanism, and a possible reaction mechanism was proposed, which revealed that the greatly improved photocatalytic activity was mainly ascribed to the high electron–hole separation and transfer efficiency. Our exploration of graphene-like BN modified with WO3 open a window for the use of other graphene-like BN based composition photocatalysis field.
Co-reporter:Jiemin Gu;Jia Yan;Zhigang Chen;Haiyan Ji;Yanhua Song;Yamin Fan;Hui Xu
Dalton Transactions 2017 vol. 46(Issue 34) pp:11250-11258
Publication Date(Web):2017/08/29
DOI:10.1039/C7DT02092A
Novel two-dimensional (2D) metal-free few-layer BN/graphene-like g-C3N4 (2D BN/g-C3N4) composites have been synthesized by a simple hydrothermal method. The construction of a 2D/2D structure between BN and g-C3N4 could shorten the migration distance of charge transfer, and provide a large contact surface. By introducing few-layer BN nanosheets into g-C3N4, the as-prepared 2D BN/g-C3N4 composites exhibited a much enhanced photocatalytic performance than that of pure g-C3N4. The 0.5% 2D BN/g-C3N4 composite possessed the most wonderful ability towards Rhodamine B (RhB) degradation irradiated by visible light, which could achieve a highest degradation efficiency of 98.2% within 120 min. Further studies revealed that modifying g-C3N4 with few-layer BN could not only facilitate the separation and transfer of photo-induced holes and electrons, but also exposed the fact that the (002) facet edges of BN terminated with –OH groups could act as catalytic sites, and thus enhance the photocatalytic activities. Moreover, the successful preparation of 2D BN/g-C3N4 composites may pave the way for fabricating other 2D composites with a layer-by-layer architecture.
Co-reporter:Jia Yan, Yamin Fan, Jiabiao Lian, Yan Zhao, Yuanguo Xu, Jiemin Gu, Yanhua Song, Hui Xu, Huaming Li
Molecular Catalysis 2017 Volume 438(Volume 438) pp:
Publication Date(Web):1 September 2017
DOI:10.1016/j.mcat.2017.05.023
•The introduction of ZnS nanospheres in GL-C3N4 was benefit for the separation of e−-h+ pairs.•ZnS/GL-C3N4 was efficient for the tetracycline degradation (a colorless antibiotic agent).•O2−, OH and holes are demonstrated as the active species in photocatalytic degradation.In this work, a novel photocatalyst ZnS nanospheres/graphene-like g-C3N4 (ZnS/GL-C3N4) nanocomposite was synthesized by a simple agitation method. Two-dimensional (2D) nanomaterial GL-C3N4, synthesized by thermal exfoliation from g-C3N4, showed large surface area and manifested efficient photocatalytic activity than bulk g-C3N4. ZnS nanospheres were well anchored and covered on the surface of GL-C3N4 nanosheets and a synergetic effect between the ZnS and GL-C3N4 could highly contributed to improvement of the light adsorption capability of GL-C3N4 as well as increasement of the separation efficiency of photon-generated e−-h+ pairs, therefore, enhancing its photocatalytic performance under the illumination of visible light. Methyl orange (MO, a kind of organic dyes which is hard to be degraded by pure C3N4) and tetracycline (TC, a representative broad-spectrum colorless antibiotic agent) were chosen as the targets of pollutants for degradation in this study. The optimum photocatalytic MO degradation of ZnS/GL-C3N4 (50%) was almost 3.48 and 12.4 times higher than that of pure ZnS and GL-C3N4, respectively. 91% TC was photodegraded in the presence of ZnS/GL-C3N4 (50%) and higher than that of GL-C3N4. Furthermore, kinetics and possible photocatalytic mechanism of MO degradation under visible light was proposed in detail. Except for the synergetic effect, the trapping experiments and ESR spectra demonstrated that not only O2− and holes, but also OH were active species playing an importing role in this system for effective degradation. Our research results open an easy pathway for developing highly efficiency photocatalyst.Download full-size image
Co-reporter:Peiwen Wu, Bilian Dai, Yanhong Chao, Yingcheng Wu, Wei Jiang, Changfeng Li, Wenshuai Zhu, Huaming Li
Molecular Catalysis 2017 Volume 436(Volume 436) pp:
Publication Date(Web):1 July 2017
DOI:10.1016/j.mcat.2017.04.008
•Three metal-free catalysts were successfully prepared.•Characterizations show the uniform dispersion of the brönsted acid ionic liquids.•A ∼100% removal of 4,6-DMDBT can be expected.•The catalytic system shows an excellent resistance to chaff interferents.•The catalysts can be recycled for 5 times.Catalytic oxidation of aromatic sulfur compounds for separation from fuel oils has turned to be an important theme in environmental protection. However, most current reports focused on metal-based catalysts, resulting in high costs and potential secondary pollution to fuel oils. In this work, three metal-free brönsted acid ionic liquids were prepared and anchored onto graphene-like hexagonal boron nitride (G-h-BN) to gain metal-free, heterogeneous catalysts. The heterogenization process not only provided convenience to recycling of the catalysts, but also supplied a sharply decreased ILs dosage. Notably, the prepared catalyst [Bmim]H2PO4/G-h-BN held the best catalytic activity, a ∼100% of catalytic activity can be gained in catalytic oxidation of 4,6-dimethyldibenzothiophene (4,6-DMDBT), which has been regarded as the most stubborn sulfide in industrial hydrodesulfurization (HDS). It was also found that distractors in fuels showed almost no influence on catalytic oxidation of 4,6-DMDBT. Besides, the catalytic oxidation product was also investigated to propose a possible reaction mechanism. The heterogeneous metal-free catalyst were recycled for 5 times without significant decrease in catalytic performance.Download full-size image
Co-reporter:Jingxia Qiu, Sheng Li, Xintai Su, Yazhou Wang, Li Xu, Shouqi Yuan, Huaming Li, Shanqing Zhang
Chemical Engineering Journal 2017 Volume 320(Volume 320) pp:
Publication Date(Web):15 July 2017
DOI:10.1016/j.cej.2017.03.054
•The Bi-NS@C composite has been synthesized via a molten salt method.•Bi nanoparticles are well-dispersed and incorporated into the carbon matrix.•The composite boosts the electric conductivity and mass transport of Na+.•The composite delivers excellent cycle performance for sodium ion battery.Sodium ion batteries (SIBs) have been considered as a promising cost-effective alternative for grid energy storage for renewable energy sources such as wind- and solar power. In this work, a bismuth nano-spheres and porous carbon composite (Bi-NS@C) is developed via an oleate-oriented dual-phase interfacial reaction and a molten salt calcination process. Materials characterizations suggest that the Bi-NS with a size of 20–30 nm are uniformly distributed in the sponge-like porous carbon network. Such a structure could enable a conductive network, prevent particle aggregation, shorten the ions transportation pathways, accommodate volume change and prevent the collapse of the electrode. As a result, this anode delivers a reversible discharge capacity of 106 mAh g−1 after even 1000 cycles at 0.2 A g−1. Even at 2 A g−1, the specific capacity of the electrode can still retain at ∼110 mAh g−1. The remarkable electrochemical performance of the Bi-NS@C composite suggests that the as-prepared nanocomposite can simultaneously enhance the Na+ ion conductivity and electronic conductivity in the charge/discharge processes, which offer guidance in anode materials design and synthesis in SIBs.
Co-reporter:Hui Liu;Yue Wang;Wanxia Ma;Hongwei Wang;Deping Wang;Wei Jiang
Chemical Papers 2017 Volume 71( Issue 8) pp:1541-1549
Publication Date(Web):07 March 2017
DOI:10.1007/s11696-017-0148-1
Four Fe-containing ionic liquids (ILs) were synthesized by coupling of conventional imidazole ionic liquids [Cxmim]Cl (x = 4, 8, 12, 16) with FeCl3 and were characterized by FT-IR, Raman, ESI–MS and TG. All of the Fe-containing ILs were applied to the conversion of fructose into 5-hydroxymethylfurfural (HMF) in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) subsequently and the result showed that [C16mim]FeCl4 exhibited excellent catalytic performance. Then the different reaction parameters with [C16mim]FeCl4 as catalyst were studied in detail. A 92.8% yield of HMF was obtained with 0.03 g [C16mim]FeCl4 and 0.1 g fructose in 1.0050 g [Bmim]Cl at 80 °C for 40 min in fructose/[Bmim]Cl solution.
Co-reporter:Xiaojie She, Jingjie Wu, Hui Xu, Zhao Mo, Jiabiao Lian, Yanhua Song, Liang Liu, Daolin Du, Huaming Li
Applied Catalysis B: Environmental 2017 Volume 202(Volume 202) pp:
Publication Date(Web):1 March 2017
DOI:10.1016/j.apcatb.2016.09.013
•In Ag/2D-C3N4/CNTs composite, the electrons can unidirectional flow from Ag to 2D-C3N4, and then to CNTs.•The enhanced photocatalytic activity is due to the efficient unidirectional transfer of the electrons with high density and efficient separation of the e-h pairs.•By ESR analysis, the photocatalytic mechanism was researched detailed.The effective separation of the electron and hole (e-h) pairs plays a key role in enhancing the photocatalytic performance of the semiconductors. The density of electrons participating in the reduction reaction also determines photocatalytic performance. We report here a rational design of a photocatalyst assembly composed of n-type semiconducting two-dimensional g-C3N4 nanosheets (2D-C3N4), carbon nanotubes (CNTs), and plasmonic Ag nanocubes, which exhibits enhanced density of electrons and controlled unidirectional change flow to promote the photocatalytic hydrogen evolution reaction. Plasmonic Ag nanocubes inject the hot-electrons into conduction band of 2D-C3N4 to increase the density of electrons while the CNTs act as a power pump of the electrons to steer electron flow from the conduction band of 2D-C3N4 to reactants. The photocatalytic performance of Ag/2D-C3N4/CNTs assembly was dramatically enhanced for the H2 evolution from water. The enhanced photocatalytic activity is due to the efficient unidirectional transfer of the electrons with high density and efficient separation of the e-h pairs.Download high-res image (144KB)Download full-size imageThe photogenerated electrons with the high density can unidirectionally flow in the composite, which can effectively enhanced the photocatalytic activity of the semiconductor.
Co-reporter:Ming Zhang, Yanchen Wei, Rui Li, Wenshuai Zhu, Hongping Li, Qi Zhang, Miao Wang, Xiao Chen, Huaming Li
Fuel 2017 Volume 209(Volume 209) pp:
Publication Date(Web):1 December 2017
DOI:10.1016/j.fuel.2017.08.001
•Hybrid magnetic POM-based mesoporous silica were facilely prepared for fast oxidation of sulfur compounds.•These hybrid materials could be easily separated by external magnets.•The materials exhibited impressive performance and long cycle life.It is of great importance to develop efficient catalysts to achieve sulfur removal in fuel, protecting the world against the pollution caused by sulfur oxides. Aiming that, polyoxometalates supported materials have been employed as a vital class of heterogeneous catalysts for oxidative desulfurization. In this study, a serial of magnetic polyoxometalates-based mesoporous silica hybrid materials were successfully prepared over a facile hydrothermal and impregnation method, and evaluated in fast oxidation of aromatic sulfur. These hybrid materials exhibited interesting feature of rapid separation by external magnets, and excellent desulfurization performance to refractory sulfur compounds (benzothiophene, 3-methylbenzothiphene, dibenzothiophene, 4-methyldibenzothiophene and 4,6-dimethyldibenzothiphene). Furthermore, the sulfur removal could still reach 94% after recycling for ten times, which could be potentially applied in industry production.Download high-res image (82KB)Download full-size image
Co-reporter:Jun Xiong, Lei Yang, Yanhong Chao, Jingyu Pang, Peiwen Wu, Ming Zhang, Wenshuai Zhu and Huaming Li
Green Chemistry 2016 vol. 18(Issue 10) pp:3040-3047
Publication Date(Web):10 Feb 2016
DOI:10.1039/C5GC02999F
h-BN has been demonstrated to be able to exhibit adsorptive desulfurization from fuel. In order to further optimize the adsorption capacities to meet the potential industrial applications, tuning the nanostructure of BN was taken into account. In this work, we demonstrated that cyanamide, dicyandiamide, and melamine as different nitrogen precursors for synthesizing BN could tune the BN nanoarchitectures. The high performance BN prepared with melamine presented a ribbon-like structure which was assembled with porous nanosheets. This kind of nanoarchitecture with exposed BN sharp edges and a porous structure can be constructed on the BN surface. The large number of low coordinated atoms at the exposed sharp edges and along the edges of the pores could build powerful interaction with sulfide, which was believed to be responsible for the advanced adsorption capacity. The prepared BN with melamine as nitrogen precursors displayed remarkable adsorption performance for DBT (40.2 mg S per g adsorbent for 500 ppm sulfur model oil and 57.5 mg S per g adsorbent according to the Langmuir isotherm model). To the best of our knowledge, it is the highest adsorption capacities reported so far for the adsorptive desulfurization. It is also noteworthy to mention that even for refractory sulfur compound 4,6-DMDBT, the prepared BN still showed high adsorption performance.
Co-reporter:Peiwen Wu, Wenshuai Zhu, Yanhong Chao, Jinshui Zhang, Pengfei Zhang, Huiyuan Zhu, Changfeng Li, Zhigang Chen, Huaming Li and Sheng Dai
Chemical Communications 2016 vol. 52(Issue 1) pp:144-147
Publication Date(Web):16 Oct 2015
DOI:10.1039/C5CC07830J
Hexagonal boron nitride nanosheets (h-BNNs) with rather high specific surface area (SSA) are important two-dimensional layer-structured materials. Here, a solvent-mediated synthesis of h-BNNs revealed a template-free lattice plane control strategy that induced high SSA nanoporous structured h-BNNs with outstanding aerobic oxidative desulfurization performance.
Co-reporter:Jun Xiong, Lei Yang, Yanhong Chao, Jingyu Pang, Ming Zhang, Wenshuai Zhu, and Huaming Li
ACS Sustainable Chemistry & Engineering 2016 Volume 4(Issue 8) pp:4457
Publication Date(Web):June 13, 2016
DOI:10.1021/acssuschemeng.6b01156
Novel BN mesoporous nanowire materials with doped oxygen atoms have been controlled and prepared successfully. Multiple techniques have been employed to determine the structure, morphology, surface feature, defects, and electronic structure. It was the first time that a controlled preparation of this unique structure was applied to adsorptive desulfurization. The obtained BN mesoporous nanowires displayed outstanding adsorptive desulfurization activity for DBT (65.4 mg S g–1 adsorbent according to the Langmuir isotherm model), which was much higher than that of commercial BN and graphene-like BN. At the same time, the BN mesoporous nanowires displayed good stability and excellent adsorption performance for the 4,6-DMDBT (33.2 mg S g–1 adsorbent). The significant enhancement of adsorption desulfurization performance of BN mesoporous nanowires was ascribed to the large number of low coordinated atoms along the nanowire surface and mesopores, which could cause an interaction with DBT, and the doped oxygen atoms further strengthen the interaction.Keywords: Adsorptive desulfurization; Boron nitride; Mesoporous nanowires; Oxygen doping
Co-reporter:Wei Jiang, Hongping Li, Chao Wang, Wei Liu, Tao Guo, Hui Liu, Wenshuai Zhu, and Huaming Li
Energy & Fuels 2016 Volume 30(Issue 10) pp:8164
Publication Date(Web):September 12, 2016
DOI:10.1021/acs.energyfuels.6b01976
Deep eutectic solvents (DESs) have been widely applied in organic synthesis, extraction processes, electrochemistry, enzymatic reactions, and many others. However, the research of DESs on extractive desulfurization of fuel is only in its infancy. Here, a new class of DESs, ionic liquid-based DESs, was synthesized and characterized, where ionic liquid was produced in situ. Among the three DESs prepared from 1-methylimidazole (MIM) and diethanolamine as hydrogen bond acceptors and propanoic acid (PA) and nitric acid as hydrogen bond donors, MIM/PA showed the highest extractive efficiency and the sulfur partition coefficient (KN) reached 2.31. The viscosity of MIM/PA is much lower than other DESs and the low-viscosity ionic liquids in the literature, which is of benefit to mass transfer. The extraction mechanism was discussed by 1H nuclear magnetic resonance, and the activity differences among aromatic sulfur compounds were explained by density functional theory calculations. The addition of p-xylene and cyclohexene in model oil has no obvious effect on extraction of dibenzothiophene, meaning that the extractive desulfurization with DESs may also be suitable for the actual fuel. Finally, the free-sulfur fuel can be obtained after 5 times extraction.
Co-reporter:Hui Xu, Haozhu Zhao, Yuanguo Xu, Zhigang Chen, Liying Huang, Yeping Li, Yanhua Song, Qi Zhang, Huaming Li
Ceramics International 2016 Volume 42(Issue 1) pp:1392-1398
Publication Date(Web):January 2016
DOI:10.1016/j.ceramint.2015.09.081
A series of three-dimensionally ordered macroporous WO3 (3DOM WO3) hybridized Ag3PO4 photocatalysts with different 3DOM WO3 contents were prepared. The composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–visible absorption spectra (UV–vis) and Fourier transform infrared (FT-IR) spectra. Under visible light irradiation, the as-prepared 3DOM WO3–Ag3PO4 composites showed enhanced photocatalytic performance for methylene blue (MB) degradation. The sample with 3DOM WO3–Ag3PO4 (4 wt%) exhibited the highest photocatalytic activity. The enhanced photocatalytic performance under visible light irradiation could be due to a synergistic effect between 3DOM WO3 and Ag3PO4. After the introduction of 3DOM WO3, the separation efficiency of the photogenerated electron-hole pairs could be increased.
Co-reporter:Xin Wang, Wei Jiang, Wenshuai Zhu, Hongping Li, Sheng Yin, Yonghui Chang and Huaming Li
RSC Advances 2016 vol. 6(Issue 36) pp:30345-30352
Publication Date(Web):14 Mar 2016
DOI:10.1039/C5RA27266A
Deep eutectic solvents (DESs), a new class of ionic liquid (IL) analogues, are easily produced through mixing Lewis or Brønsted acid and base. In this study, a class of DESs was prepared by mixing low cost triethylamine and organic acid with different molar ratios. It was found that the base/acid molar ratio (B/A) played an outstanding role in the solubility and extractive ability of DESs. When B/A was 1:3 and 1:5, the loss of DESs in model oil was even less than 0.003%. Take the DES with B/A = 1:3 for example, the extraction ability of DESs showed the following order [TEtA][Pr] > [TEtA][Ac] > [TEtA][Fo], which could be explained by 1H NMR analysis. The extractive mechanism was also discussed by density functional theory (DFT) calculations. The sulfur partition coefficient (KN) was 2.14 using [TEtA][Pr] as the extractant, and the sulfur content could be reduced from 500 ppm to 10 ppm after four times extraction.
Co-reporter:Bilian Dai, Peiwen Wu, Wenshuai Zhu, Yanhong Chao, Jia Sun, Jun Xiong, Wei Jiang and Huaming Li
RSC Advances 2016 vol. 6(Issue 1) pp:140-147
Publication Date(Web):08 Dec 2015
DOI:10.1039/C5RA23272D
A peroxomolybdate ionic liquid (PMo IL) was synthesized and further immobilized on graphene-like hexagonal boron nitride (PMo IL/G-h-BN). Compared with the homogenous PMo IL, the heterogeneous catalyst presented an enhanced catalytic and recyclable performance in oxidative desulfurization. The influence of different desulfurization systems, different carriers and reaction conditions indicated that the PMo IL/G-h-BN exhibited a good catalytic activity with hydrogen peroxide as the oxidant in oxidation of dibenzothiophene (DBT). The catalytic activity of PMo IL/G-h-BN shows a superior performance compared to those of other carriers supported with PMo IL catalysts, reaching 98.5% sulfur removal on DBT. This G-h-BN heterogenization of the IL strategy not only reduced the usage amount of IL active species greatly, but also enhanced the recycling performance of the catalyst. The mechanism of adsorption and catalytic oxidative desulfurization was investigated by gas chromatography-mass spectrometry (GC-MS).
Co-reporter:Tingting Zhu, Liying Huang, Yanhua Song, Zhigang Chen, Haiyan Ji, Yeping Li, Yuanguo Xu, Qi Zhang, Hui Xu and Huaming Li
New Journal of Chemistry 2016 vol. 40(Issue 3) pp:2168-2177
Publication Date(Web):15 Dec 2015
DOI:10.1039/C5NJ02094H
Graphene-like MoS2 photocatalysts were synthesized by the hydrothermal method. The obtained graphene-like MoS2/Ag3VO4 composites were characterized using a series of techniques to determine their structures and properties. Due to elevated photogenerated electron separation and strong hole oxidizability as well as light harvesting, the obtained graphene-like MoS2/Ag3VO4 composites display enhanced properties for the degradation of methylene blue (MB) and rhodamine B (RhB) in comparison with pure Ag3VO4 under visible light illumination. The degradation kinetics of the graphene-like MoS2/Ag3VO4 composites for MB and RhB were calculated to demonstrate their excellent photocatalytic activities. Electrochemical impedance spectroscopy (EIS) Nyquist plots were obtained to determine the electron transfer and recombination processes of the graphene-like MoS2/Ag3VO4 composite. The possible photocatalytic mechanism of the graphene-like MoS2/Ag3VO4 composites is proposed based on active species trapping experiments. Results show that the formative interface between graphene-like MoS2 and Ag3VO4 accelerates the electron transfer performance.
Co-reporter:Jinyuan Liu, Jia Yan, Haiyan Ji, Yuanguo Xu, Liying Huang, Yeping Li, Yanhua Song, Qi Zhang, Hui Xu, Huaming Li
Materials Science in Semiconductor Processing 2016 Volume 46() pp:59-68
Publication Date(Web):May 2016
DOI:10.1016/j.mssp.2015.11.013
In this study, an ordered mesoporous g-C3N4 (ompg-C3N4) photocatalyst was synthesized successfully using silica material SBA-15 as the hard template via an impregnation method at different calcinations temperatures. The as-prepared samples were characterized by Brunauer–Emmett–Teller, Barrett–Joyner–Halenda, scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared spectroscopy, wide and small angle X-ray diffraction, and UV–vis diffuse reflectance spectroscopy. The prepared materials were also evaluated to determine their photocatalytic degradation activities against methylene blue and rhodamine B under visible light irradiation. The calcination temperature greatly affected the structure and photocatalytic activity of ompg-C3N4. The sample calcined at 550 °C had the largest specific surface area and the highest photocatalytic activity, which were attributable to the characteristic confined space effect found in ordered mesoporous materials as well as the ordered mesoporous structure. A free radicals trapping test indicated that holes and ⋅O2− were the main active species related to photocatalytic degradation.
Co-reporter:Wei Liu, Wei Jiang, Wangqin Zhu, Wenshuai Zhu, Hongping Li, Tao Guo, Weihua Zhu, Huaming Li
Journal of Molecular Catalysis A: Chemical 2016 Volume 424() pp:261-268
Publication Date(Web):1 December 2016
DOI:10.1016/j.molcata.2016.08.030
•Different deep eutectic solvents were applied for oxidative desulfurization.•Desulfurization efficiency can be greatly promoted by adding a few amount of DES.•The neutral DES ChCl/2PEG showed the best performance.•The oxidative products DBTO and DBTO2 were proved by GC–MS analysis.In this study, a new type of “green solvents” named deep eutectic solvents (DESs) has been synthesized by combining hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs). Choline chloride (ChCl) was chosen as typical HBA, and polyethylene glycol (PEG), 1,3-butyleneglycol (BG), ethylene glycol (EG), glycerol (Gl), propionate (Pr), malonic acid (MA) and urea (U) were chosen as HBDs. The extraction and catalytic oxidative desulfurization (ECODS) system was evaluated with phosphotungstic acid (HPW) as catalyst and 30 wt% H2O2 as oxidant. Among all the neutral, acid and basic DESs, choline chloride/2polyethylene glycol (ChCl/2PEG) showed the best performance and 99.1% of dibenzothiophene (DBT) could be eliminated from model oil at 50 °C within 3 h. Interestingly, the volume ratio of DES to model oil was just 1:10, which was much less than the amount of extractant in the literature. The gas chromatography–mass spectrometer (GC–MS) analysis demonstrated that DBT sulfoxide (DBTO) and sulfone (DBTO2) were the products of oxidation of DBT. The desulfurization efficiency of the five sulfides in ECODS system occured in the following order: DBT > 4-MDBT > 4,6-DMDBT > 3-MBT >BT.Different deep eutectic solvents combining choline chloride (ChCl) and hydrogen bond donor were synthesized and used as w new green solvent in the field of oxidative desulfurization. Dibenzothiophene (DBT) in model oil was removed completely in ChCl/2PEG with HPW as catalyst in the presence of H2O2 under mild conditions. The oxidation products consist of sulfoxide DBTO and sulfone DBTO2.
Co-reporter:Siwen Zhu, Hongping Li, Wenshuai Zhu, Wei Jiang, Chao Wang, Peiwen Wu, Qi Zhang, Huaming Li
Journal of Molecular Graphics and Modelling 2016 Volume 68() pp:158-175
Publication Date(Web):July 2016
DOI:10.1016/j.jmgm.2016.05.003
•The calculated spectra agree well with the experimental results. Experimental characteristic peaks have been assigned.•Redshifts were observed and the formation of hydrogen bonds mainly contributes to the redshifts.•Both of the B3LYP and B3LYP-D3 are excellent to reproduce the experimental results.•The hydrogen bonds were proved to exist in DESs between the HBD and HBA by structure analysis and RDG analysis.Deep eutectic solvents (DESs), as ionic liquid analogues for green solvents, have gained increasing attentions in chemistry. In this work, three typical kinds of DESs (ChCl/Gly, ChCl/AcOH and ChCl/Urea) were successfully synthesized and characterized by Fourier transform infrared spectroscopy (FTIR) and Raman. Then comprehensive and systematical analyses were performed by the methods of density functional theory (DFT). Two methods (B3LYP/6-311 + +G(2d,p) and dispersion-corrected B3LYP-D3/6-311 + +G(2d,p)) were employed to investigate the structures, vibrational frequencies and assign their ownership of vibrational modes for the DESs, respectively. Nearly all the experimental characteristic peaks of IR and Raman were identified according to the calculated results. By linear fitting of the combined calculated vs experimental vibration frequencies, it can be found that both of the two methods are excellent to reproduce the experimental results. Besides, hydrogen bonds were proved to exist in DESs by IR spectrum, structure analysis and RDG analysis. This work was aimed at predicting and understanding the vibrational spectra of the three typical DESs based on DFT methods. Moreover, by comparing experimental and theoretical results, it provides us a deep understanding of the formation mechanisms of DESs.A bridge connecting experiment and calculation for deep eutectic solvents (DESs) has been built by density functional theory. The infrared and Raman spectra have been calculated to compare with experiment. Almost all the experimental characteristic peaks can be assigned according to computational results. Structure analysis and reduced density gradient analysis (RDG) have been carried out to deep understand the interactions in deep eutectic solvents.
Co-reporter:Haiyan Ji, Jia Sun, Peiwen Wu, Bilian Dai, Yanhong Chao, Ming Zhang, Wei Jiang, Wenshuai Zhu, Huaming Li
Journal of Molecular Catalysis A: Chemical 2016 Volume 423() pp:207-215
Publication Date(Web):November 2016
DOI:10.1016/j.molcata.2016.06.019
•Microporous h-BN is employed as a confining support for heterogenization of HPW.•The obtained HPW/h-BN show ∼100% sulfur removal from fuel oil.•Confining effect is key to the high catalytic activity.•The HPW/h-BN can be recycled for 6 times.Hexagonal boron nitride (h-BN), a layer structure material, has gained increasing attentions as a support. Herein, a few-layer h-BN is constructed and employed as an interlayer confining support for heterogenization of phosphotungstic acid (HPW/h-BN). The obtained HPW/h-BN is applied in oxidative desulfurization (ODS) and a ∼100% of sulfur removal can be achieved. Detailed experiments show that porous structure of h-BN, functioned as confining sites, contributes to the remarkable catalytic activity. Besides, aromatic hydrocarbon and olefin are further applied as chaff interferent in ODS showing no obvious effects, suggesting a promising prospect. This catalyst presents preferable recyclability in ODS, which can be recycled 6 times without noticeable decrease in reactivity. Moreover, the reaction mechanism and resultant are instantly detected by gas chromatography-mass spectrometry.
Co-reporter:Jun Xiong, Wenshuai Zhu, Hongping Li, Lei Yang, Yanhong Chao, Peiwen Wu, Suhang Xun, Wei Jiang, Ming Zhang and Huaming Li
Journal of Materials Chemistry A 2015 vol. 3(Issue 24) pp:12738-12747
Publication Date(Web):01 May 2015
DOI:10.1039/C5TA01346A
Novel carbon-doped porous boron nitride (C-BN) has been successfully prepared by using 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) as a soft template and the carbon source via calcination under N2 atmosphere. Multiple techniques were applied to investigate the structure, morphology, and adsorptive desulfurization performance. The metal-free porous C-BN displayed enhanced adsorption performance for dibenzothiophene (DBT) than pure BN materials and exhibited one of the highest adsorption capacities reported up to now (49.75 mg S g−1 adsorbent according to the Langmuir isotherm model, 35.2 mg S g−1 adsorbent for 500 ppm sulfur model oil). After three times recycling, the adsorption capacity slightly decreased from 35.2 to 27.2 mg S g−1 adsorbent. The excellent adsorption performance of porous C-BN was attributed to the more exposed atoms along the edges of the pores and the stronger Lewis acid–base interactions between DBT and carbon-doped porous BN. Moreover, it is believed that this strategy to control the structure and composition of BN can be extended to incorporate other heteroatoms and control the pore size for BN materials by changing the anion or cation of the ionic liquids.
Co-reporter:Yanhua Song, Yucheng Lei, Hui Xu, Cheng Wang, Jia Yan, Haozhu Zhao, Yuanguo Xu, Jiexiang Xia, Sheng Yin and Huaming Li
Dalton Transactions 2015 vol. 44(Issue 7) pp:3057-3066
Publication Date(Web):05 Dec 2014
DOI:10.1039/C4DT03242J
Novel few-layer MoS2/Ag3PO4 composites were fabricated. The results indicated that Ag3PO4 nanoparticles were directly formed on the surface of few-layer MoS2. The physical and chemical properties of the few-layer MoS2/Ag3PO4 composite photocatalysts were tested in order to investigate the effects of few-layer MoS2 on the photocatalytic activity of Ag3PO4. The photocatalytic activity of the few-layer MoS2/Ag3PO4 composites was evaluated by the photocatalytic degradation of Rhodamine B (RhB) and bisphenol A (BPA) under visible light irradiation. The photocatalytic activity of the few-layer MoS2/Ag3PO4 composites was higher than that of pure Ag3PO4. The optimal few-layer MoS2 content for the organic pollutant degradation of the heterojunction structures was determined. The synergic effect between few-layer MoS2 and Ag3PO4 was found to lead to an improved photogenerated carrier separation. The stability and the possible photocatalytic mechanism of the composites were also discussed.
Co-reporter:Xiaojie She, Hui Xu, Hefei Wang, Jiexiang Xia, Yanhua Song, Jia Yan, Yuanguo Xu, Qi Zhang, Daolin Du and Huaming Li
Dalton Transactions 2015 vol. 44(Issue 15) pp:7021-7031
Publication Date(Web):26 Jan 2015
DOI:10.1039/C4DT03793F
This research has developed a photocatalytic reactor that includes circulating water, light, and a temperature control system. CeO2/g-C3N4 composites with high photocatalytic activity and stability were synthesized by a simple and facile hydrothermal method. The obtained photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It was found that in the CeO2/g-C3N4 composites, the CeO2 nanoparticles were homogeneously cubic in shape (from 3 to 10 nm) and were evenly dispersed on the surface of the g-C3N4. At constant temperature (30 °C), 5% CeO2/g-C3N4 photocatalyst showed the best photocatalytic activity for degrading organic dye methylene blue (MB) under visible light irradiation. The photocatalytic reaction for degrading MB followed first-order kinetics and 5% CeO2/g-C3N4 exhibited a higher apparent rate of 1.2686 min−1, 7.8 times higher than that of the pure g-C3N4 (0.1621 min−1). In addition, it was found that 5% CeO2/g-C3N4 had a new property that it could be used as a sensor for the determination of trace amounts of Cu2+. Such unique design and one-step synthesis, with an exposed high-activity surface, are important for both technical applications and theoretical investigations.
Co-reporter:Hongping Li, Yonghui Chang, Wenshuai Zhu, Changwei Wang, Chao Wang, Sheng Yin, Ming Zhang and Huaming Li
Physical Chemistry Chemical Physics 2015 vol. 17(Issue 43) pp:28729-28742
Publication Date(Web):22 Sep 2015
DOI:10.1039/C5CP04172D
The nature of the interaction between deep eutectic solvents (DESs), formed by ChCl and glycerol, and SO2 has been systematically investigated using the M06-2X density functional combined with cluster models. Block-localized wave function energy decomposition (BLW-ED) analysis shows that the interaction between SO2 and DESs is dominated by a charge transfer interaction. After this interaction, the SO2 molecule becomes negatively charged, whereas the ChCl–glycerol molecule is positively charged, which is the result of Lewis acid–base interaction. The current result affords a theoretical proof that it is highly useful and efficient to manipulate the Lewis acidity of absorbents for SO2 capture. Moreover, hydrogen bonding as well as electrostatic interactions may also contribute to the stability of the complex. Structure analysis shows that solvent molecules will adjust their geometries to interact with SO2. In addition, the structure of SO2 is barely changed after interaction. The interaction energy between different cluster models and SO2 ranges from −6.8 to −14.4 kcal mol−1. It is found that the interaction energy is very sensitive to the solvent structure. The moderate interaction between ChCl–glycerol and SO2 is consistent with the concept that highly efficient solvents for SO2 absorption should not only be solvable but also regenerable.
Co-reporter:Hui Xu, Jiaxiang Zhu, Yongxiu Song, Tingting Zhu, Wenkai Zhao, Yanhua Song, Zulin Da, Chengbao Liu, Huaming Li
Journal of Alloys and Compounds 2015 Volume 622() pp:347-357
Publication Date(Web):15 February 2015
DOI:10.1016/j.jallcom.2014.09.148
•The novel AgX/Ag2CO3 composites have been synthesized by ion exchange reaction.•AgX/Ag2CO3 exhibit higher photoactivity and stability than that of Ag2CO3.•The band structure of AgX/Ag2CO3 is beneficial to improve the photoactivity.The novel visible-light-driven AgX/Ag2CO3 (X = Cl, I) hybrid materials were synthesized by ion exchange reaction. The physical and chemical properties of the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), diffuse-reflection spectra (DRS) and photocurrent techniques. The as-prepared AgX/Ag2CO3 (X = Cl, I) composites showed higher photocatalytic activity than that of the pure Ag2CO3 photocatalyst under visible light irradiation (λ ⩾ 400 nm) in the process of methylene blue (MB) degradation. The optimal mass percentage of AgCl and AgI in the AgX/Ag2CO3 (X = Cl, I) composite was 20.54 wt% and 40 wt%, respectively. The enhancement of photocatalytic activity was attributed to the suitable band potential between AgX and Ag2CO3, which was beneficial to increase the separation efficiency of electrons and holes. Besides, the photocatalytic mechanism of AgX/Ag2CO3 (X = Cl, I) composites was also proposed.
Co-reporter:Weibin Li, Qi Wang, Liying Huang, Yeping Li, Yuanguo Xu, Yanhua Song, Qi Zhang, Hui Xu and Huaming Li
RSC Advances 2015 vol. 5(Issue 108) pp:88832-88840
Publication Date(Web):09 Oct 2015
DOI:10.1039/C5RA15417K
Bi2WO6 modified with few-layer BN was synthesized by an impregnation method. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflection spectroscopy (DRS) and Fourier transform infrared spectroscopy (FT-IR). The as-prepared BN/Bi2WO6 photocatalysts exhibited a higher photocatalytic activity for the degradation of Rhodamine B (RhB) than the pure Bi2WO6. The 3 wt% BN/Bi2WO6 photocatalyst showed the best photocatalytic activity and high stability after five runs under visible light irradiation. The enhanced visible-light photocatalytic activity could be attributed to the synergetic effect of few-layer BN and Bi2WO6.
Co-reporter:Jun Xiong, Wenshuai Zhu, Wenjing Ding, Lei Yang, Ming Zhang, Wei Jiang, Zhen Zhao and Huaming Li
RSC Advances 2015 vol. 5(Issue 22) pp:16847-16855
Publication Date(Web):09 Jan 2015
DOI:10.1039/C4RA14382E
Hydrogen peroxide is usually used as an oxidant in oxidative desulfurization. However, in order to reach a high level of sulfur removal, excess of hydrogen peroxide needs to be added into the oxidative system. In this study, phosphomolybdic acid immobilized on imidazole-based ionic liquid modified mesoporous SBA-15 (HPMo-IL/SBA-15) was prepared. The as-prepared material combines the advantages of H3PMo12O40 (HPMo) and SBA-15. The high special surface area of SBA-15 could well disperse the HPMo active species. The results show that HPMo could be steadily immobilized across the surface of SBA-15 by using an imidazole-based ionic liquid. At the same time, after the introduction of the imidazole-based ionic liquid, HPMo-IL/SBA-15 material exhibited hydrophobic property. Experiments demonstrated that the hydrophobic catalyst exhibited a high activity in oxidative desulfurization. When hydrogen peroxide with a stoichiometric ratio (H2O2/sulfur mole ratio is 2) was used, the removal of dibenzothiophene (DBT) could achieve levels of above 90% at 60 °C in 90 min. When the concentration of hydrogen peroxide was slightly increased (H2O2/sulfur mole ratio increased from 2 to 2.5), the sulfur removal reached 100% in 40 min. Moreover, the synthesis catalyst could adsorb dibenzothiophene sulfone (DBTO2), which is the oxidant product of DBT. In this regard, HPMo-IL/SBA-15 served as not only a high-efficiency catalyst but also an adsorbent.
Co-reporter:Hui Liu, Hongwei Wang, Yuan Li, Wei Yang, Changhua Song, Huaming Li, Wenshuai Zhu and Wei Jiang
RSC Advances 2015 vol. 5(Issue 12) pp:9290-9297
Publication Date(Web):10 Dec 2014
DOI:10.1039/C4RA09131K
In this work, D001-cc cation-exchange resin was modified by CrCl3 using an ion exchange method to obtain a Cr3+-D001-cc catalyst. FT-IR, UV-vis, SEM, EDX, ICP-OES and Py-IR were used to characterize the catalyst. Subsequently, the effects of the modified metal ion and different cation-exchange resin on the direct conversion of glucose to 5-hydroxymethylfurfural in [Bmim]Cl were examined. The results showed that Cr3+-D001-cc resin exhibited excellent catalytic performance. Moreover, with Cr3+-D001-cc resin as a catalyst, the influence of the reaction conditions on the dehydration of glucose was investigated in detail. 61.3% yield of 5-hydroxymethylfurfural was achieved in the [Bmim]Cl ionic liquid at 110 °C for 30 min with 0.1 g catalyst. Finally, a recycling experiment was performed. The result indicated that the HMF yield in the Cr3+-D001-cc resin and [Bmim]Cl system significantly decreased after six recycles.
Co-reporter:Haiyan Ji, Xiaocui Jing, Yuanguo Xu, Jia Yan, Hongping Li, Yeping Li, Liying Huang, Qi Zhang, Hui Xu and Huaming Li
RSC Advances 2015 vol. 5(Issue 71) pp:57960-57967
Publication Date(Web):08 Jun 2015
DOI:10.1039/C5RA07148H
Composite photocatalysts have attracted considerable attention in the exploration of both highly efficient and low cost materials. In this study, novel magnetic g-C3N4/NiFe2O4 photocatalysts were fabricated by a facile chemisorption method. X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectroscopy (IR), UV-vis diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS) were utilized to analyze the structure and properties of samples, which indicated that NiFe2O4 had been integrated onto the surface of g-C3N4 successfully. The as-prepared 7.5% g-C3N4/NiFe2O4, with the best photocatalytic activity, can maintain high photocatalytic activity and stability after five runs in the presence of hydrogen peroxide under visible light irradiation. During the catalytic reaction, the synergistic effect between g-C3N4 and NiFe2O4 can accelerate photogenerated charge separation and facilitate the photo-Fenton process to get an enhanced photocatalytic activity. Moreover, the collection and recycling of photocatalyst was readily achieved owing to the distinctive magnetism of g-C3N4/NiFe2O4.
Co-reporter:Yuanguo Xu, Meng Xie, Shuquan Huang, Hui Xu, Haiyan Ji, Jiexiang Xia, Yeping Li and Huaming Li
RSC Advances 2015 vol. 5(Issue 33) pp:26281-26290
Publication Date(Web):27 Feb 2015
DOI:10.1039/C5RA01206F
Nano-size g-C3N4 derivatives were fabricated by a simple dissolve-regrowth method in HNO3 solution followed by a calcination process. X-ray diffraction (XRD), Z-potential, elemental analysis and IR are used to investigate the structure, composition and the properties of the samples. Scanning electron microscopy (SEM) shows the average size of the nano-size g-C3N4 derivatives increases with increasing calcination temperature. Methyl orange (MO) dye was used as the target pollutant to investigate the photoactivity of the samples. The pure g-C3N4 can only degrade about 1.1% MO, while the g-C3N4 derivatives calcined at 300 °C can decompose about 31.9% of MO in 4 h. Besides, when a small amount of methylene blue (MB) solution was introduced, the g-C3N4–HNO3-300 can decompose about 75.8% in 4 h. The photoactivity of g-C3N4 was greatly enhanced after the modification process (especially with the assistance of MB). Additionally, this work supplied a simple method to modify materials with enhanced photoactivity. Finally, the possible reactive species and the possible mechanism were proposed based on Electron spin resonance (ESR) and XPS results.
Co-reporter:Zhao Mo, Xiaojie She, Yeping Li, Liang Liu, Liying Huang, Zhigang Chen, Qi Zhang, Hui Xu and Huaming Li
RSC Advances 2015 vol. 5(Issue 123) pp:101552-101562
Publication Date(Web):10 Nov 2015
DOI:10.1039/C5RA19586A
In this paper, a simple preparation method was utilized to study for the optimum calcination temperature of graphitic carbon nitride (g-C3N4). The g-C3N4 prepared at different temperatures were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS) and so on. The results demonstrated that g-C3N4 could not be formed fully until the calcination temperature was higher than 500 °C. From DRS and photoluminescence (PL) spectrum, a red shift of absorption peaks with increasing calcination temperatures was found. This could enhance the visible light absorption, and then the photocatalytic activity would be improved. The photocatalytic activity was evaluated via the photodegradation of methylene blue (MB) and 4-chlorophenol (4-CP), respectively. Moreover, due to the gradual decrement trend of photocurrent intensity with addition of MB, g-C3N4 prepared at 650 °C could be used as a photoelectrochemical sensor to detect the existence of MB and estimate the concentration of MB. Hence g-C3N4 will become a promising candidate for photoelectrochemical applications.
Co-reporter:Yanhong Chao;Wenshuai Zhu;Zhihong Ye;Peiwen Wu;Nannan Wei;Xiangyang Wu
Journal of Applied Polymer Science 2015 Volume 132( Issue 15) pp:
Publication Date(Web):
DOI:10.1002/app.41803
ABSTRACT
In this study, the strong-acid polystyrene resin D001 was modified by impregnation with metal ions Fe3+, Cu2+, and Zn2+ to prepare new kinds of sorbents. The modified D001 was characterized by N2 sorption–desorption isotherms, X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The sorption performance of the metal modified resins for removal of antibiotics tetracycline (TC) and doxycycline (DC) from aquatic environment was investigated and excellent sorption capability with more than 98% removal ratio was observed for these resins after modification. Although these modified resins also presented pH-dependent sorption, they showed much better flexibility with pH fluctuation than those of the unmodified original D001, and extremely strong sorption capability was exhibited in a wide range of pH 2–8 for both TC and DC. Pseudo-second-order kinetic equation described the sorption process more reasonably than pseudo-first-order equation. Langmuir isotherm model provided the best match to the equilibrium data with monolayer maximum sorption capacity of 417–625 mg g−1 under 288–318 K. The sorption capacity decreased with the increase of ionic strength of NaCl. The main sorption mechanism was proposed to be surface complexation, cation bridge interaction and electrostatic attraction/competition between antibiotics and metal modified resins. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41803.
Co-reporter:Ming Zhang;Wenshuai Zhu;Suhang Xun;Jun Xiong;Wenjing Ding;Meng Li;Qian Wang
Chemical Engineering & Technology 2015 Volume 38( Issue 1) pp:117-124
Publication Date(Web):
DOI:10.1002/ceat.201400023
Abstract
Functional mesoporous Mo–SiO2 materials were synthesized by a one-pot and facile room-temperature procedure, and characterized by X-ray diffraction, TEM, Raman spectroscopy, FT-IR, diffuse reflectance spectra, and BET analysis. The experimental results demonstrated that the mesoporous materials presented a high dispersion of molybdenum species and excellent catalytic activity for the removal of dibenzothiophene (DBT) without organic solvents as extractants. The catalytic performance on different sulfur-containing compounds was also investigated in detail. After recycling for eight times, the removal of the oxidation desulfurization system could still reach high values. GC-MS analysis detected the oxidation product of DBT. A mechanism was proposed for the absorptive oxidation process of sulfur compounds.
Co-reporter:Hui Xu, Haozhu Zhao, Yanhua Song, Wei Yan, Yuanguo Xu, Hongping Li, Liying Huang, Sheng Yin, Yeping Li, Qi Zhang, Huaming Li
Materials Science in Semiconductor Processing 2015 Volume 39() pp:726-734
Publication Date(Web):November 2015
DOI:10.1016/j.mssp.2015.04.013
The g-C3N4 was synthesized by a hydrothermal method and the g-C3N4/Ag3PO4 composites were prepared by a ordinary precipitation method. Microstructures, morphologies and optical properties of the as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), UV–vis diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). The results showed that the Ag3PO4 nanoparticles were dispersed on the surface of the flake-like g-C3N4, and the heterojunction was formed on the interface. The g-C3N4/Ag3PO4 (2 wt%) photocatalyst presented the highest photocatalytic activity for organic dye methylene blue (MB) degradation, and its photocurrent intensity was approximately 2 times than that of the pure Ag3PO4. The g-C3N4/Ag3PO4 (2 wt%) photocatalyst also exhibited photocatalytic performance in the decomposition of colorless antibiotic ciprofloxacin (CIP). The capture experiment confirmed that holes acted as the main active species during the photocatalytic reaction.
Co-reporter:Hui Liu, Chun Hua, Changhua Song, Shifeng Dai, Hongwei Wang, Wenshuai Zhu, Huaming Li
Inorganica Chimica Acta 2015 Volume 428() pp:32-36
Publication Date(Web):24 March 2015
DOI:10.1016/j.ica.2015.01.016
•(NH4)2S2O3 and [Bmim]Cl could be an excellent combination for the conversion of fructose to HMF.•The catalytic system had a good tolerance for high concentration fructose and water.•The catalytic system exhibited constant stability and activity.Some sulfur oxyacid salts with weak acidity or alkalinity, including Na2SO4, (NH4)2SO4, (NH4)2S2O3 and Na2S2O3, were applied to the conversion of fructose to 5-hydroxymethylfurfural. The results indicated that (NH4)2S2O3 had excellent catalytic performance for the conversion of fructose. A desired HMF yield of 81.6% was obtained with only 5 mg (NH4)2S2O3 as the catalyst in [Bmim]Cl at 120 °C for 50 min. Furthermore, the HMF yield remained at 76.6% with 60 wt% water in the IL–water mixture solvent. In addition, the system of (NH4)2S2O3 and [Bmim]Cl exhibited a constant stability and activity, and a good HMF yield was maintained after nine recycles.A agreeable HMF yield of 81.6% was reached with only 5 mg (NH4)2S2O3 as the catalyst in [Bmim]Cl at 120 °C for 50 min, although S2O32− had the similar structure as SO42−.
Co-reporter:Yeping Li, Shilong Wu, Liying Huang, Hui Xu, Rongxian Zhang, Minglan Qu, Qiang Gao, Huaming Li
Journal of Physics and Chemistry of Solids 2015 Volume 76() pp:112-119
Publication Date(Web):January 2015
DOI:10.1016/j.jpcs.2014.08.012
•Novel g-C3N4/Bi2O3 composites were synthesized by a mixing-calcination method.•The g-C3N4/Bi2O3 composites show high visible-light photocatalytic performance.•The enhanced photocatalytic activity is mainly attributed to effective separation of electron and hole.Novel g-C3N4 modified Bi2O3 (g-C3N4/Bi2O3) composites were synthesized by a mixing-calcination method. The samples were characterized by thermogravimetry (TG), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), UV–vis diffuse reflection spectroscopy (DRS), photoluminescence (PL) and photocurrent-time measurement (PT). The photocatalytic activity of the composites was evaluated by degradation of Rhodamine B (RHB) and 4-chlorophenol (4-CP) under visible light irradiation (>400 nm). The results indicated that the g-C3N4/Bi2O3 composites showed higher photocatalytic activity than that of Bi2O3 and g-C3N4. The enhanced photocatalytic activity of the g-C3N4/Bi2O3 composites could be attributed to the suitable band positions between g-C3N4 and Bi2O3. This leads to a low recombination between the photogenerated electron–hole pairs. The proposed mechanism for the enhanced visible-light photocatalytic activity of g-C3N4/Bi2O3 composites was proven by PL and PT analysis.
Co-reporter:Hongping Li, Yonghui Chang, Wenshuai Zhu, Wei Jiang, Ming Zhang, Jiexiang Xia, Sheng Yin, and Huaming Li
The Journal of Physical Chemistry B 2015 Volume 119(Issue 19) pp:5995-6009
Publication Date(Web):April 24, 2015
DOI:10.1021/acs.jpcb.5b00516
In this work, the interaction nature between [BMIM]+[AlCl4]− ionic liquid (IL) and aromatic sulfur compounds (thiophene, benzothiophene, and dibenzothiophene) has been studied by means of density functional theory (M06-2X functional) combined with an implicit solvation model. Although [BMIM]+[AlCl4]− is a metal-containing IL, its extractive desulfurization mechanism is different from other metal-containing ILs but similar to non-metal-containing ILs. Important reactions involved in extractive desulfurization (EDS) were systematically studied. Our results have demonstrated that both the cation and the anion play important roles in EDS. On the basis of the structure analysis, reduced density gradient analaysis (RDG), and energy decomposition analysis, [BMIM]+ cation affords a π–π interaction while [AlCl4]− anion provides a hydrogen bonding interaction. Electrostatic potential analysis implies the dominant π–π interaction and hydrogen bonding interaction are driven by electrostatic interaction between IL and aromatic sulfur compounds. Interaction energy between [BMIM]+[AlCl4]− and thiophene (TH), benzothiophene (BT), and dibenzothiophene (DBT) follows the order TH < BT < DBT. Moreover, Al-containing IL with a high molar ratio of AlCl3 ([BMIMCl]/2[AlCl3]) has also been studied. Results show that [Al2Cl7]− species will be formed with excess AlCl3. However, the [Al2Cl7]−-based IL cannot improve the EDS performance. Improvement of EDS performance with a high molar ratio of AlCl3 is credited to the Lewis acidity of AlCl3. Charge analysis reveals that there is no obvious charge transfer during the reaction, which is different from Fe-containing ILs as well as solid sorbents. In addition, CH−π interaction is not important for the current system.
Co-reporter:Hongping Li, Wenshuai Zhu, Yonghui Chang, Wei Jiang, Ming Zhang, Sheng Yin, Jiexiang Xia, Huaming Li
Journal of Molecular Graphics and Modelling 2015 Volume 59() pp:40-49
Publication Date(Web):June 2015
DOI:10.1016/j.jmgm.2015.03.007
•A coordination structure has been found in extractive desulfurization by using [BMIM]+[FeCl4]− ionic liquid.•Interaction energy and extraction selectivity follow the order: TS < DBT ≈ BT.•The alkyl group for TS and BT may improve the interaction energy and extraction selectivity.•NBO results show that the mechanism of this extractive desulfurization is determined by charge transfer.In this work, interaction nature between a group of aromatic sulfur compounds and [BMIM]+[FeCl4]− have been investigated by density functional theory (DFT). A coordination structure is found to be critical to the mechanism of extractive desulfurization. Interaction energy and extractive selectivity follow the order: thiophene (TH) < dibenzothiophene (DBT) ≈ benzothiophene (BT). Alkylation of TH or BT (e.g. 3-methylthiophene, and 3-methylbenzothiophene) leads to a stronger interaction with ionic liquid, but steric hindrance effects of some alkylic derivatives (e.g. 2,7-dimethylbenzothiophene) lead to a weaker interaction with ionic liquid. The mechanism of extractive desulfurization is attributed to the charge transfer effect. During extractive desulfurization, electrons on aromatic sulfur compounds transfer into the Lewis part of ionic liquid, namely, [FeCl4]−. Furthermore, it is better to consider the Lewis acidity of Fe-containing ionic liquid by the whole unit (such as [FeCl4]− and aromatic sulfur compounds (X)) rather than only Fe or S atom.Desulfurization of aromatic sulfur compounds is attributed to a coordination interaction by [BMIM]+[FeCl4]− ionic liquid. The interaction energy and selectivity is linearly related to the amount of charge transfer between them.
Co-reporter:Xiaojie She, Hui Xu, Yuanguo Xu, Jia Yan, Jiexiang Xia, Li Xu, Yanhua Song, Yan Jiang, Qi Zhang and Huaming Li
Journal of Materials Chemistry A 2014 vol. 2(Issue 8) pp:2563-2570
Publication Date(Web):12 Nov 2013
DOI:10.1039/C3TA13768F
Due to their unprecedented electronic, surface and optical properties, the atomic-thick graphene-like materials have aroused great interest. Compared with the bulk counterparts, the graphene-like material can not only enhance the internal properties, but also gives rise to new promising properties. Herein, the graphene-like carbon nitride (graphene-like C3N4) was synthesized via liquid exfoliation from the bulk graphitic carbon nitride (g-C3N4) in 1,3-butanediol (1,3-BUT) for the first time. And the graphene-like C3N4 was characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), thermogravimetric analysis (TG), and X-ray photoelectron spectroscopy (XPS). The obtained graphene-like C3N4 exhibited a two-dimensional thin-layer structure with about 3–6 atoms thickness, a high specific surface area of 32.54 m2 g−1, increased photocurrent responses, improved electron transport ability and enhanced photocatalytic activity. The photocatalytic reaction for the organic dye methylene blue (MB) by the graphene-like C3N4 followed first-order kinetics. Moreover, the graphene-like C3N4 exhibited a higher apparent rate of 0.1262 min−1, which was 3.1 times higher than that of the bulk g-C3N4 (0.0409 min−1). The enhanced photocatalytic reaction was due to a high specific surface area and a larger bandgap (by 0.14 eV). The yield of the graphene-like C3N4 was up to ∼0.35 mg mL−1. Moreover, the graphene-like C3N4 had a new property that it could be used as the sensor for trace amounts of Cu2+ determination, so the graphene-like C3N4 is a new but promising candidate for heavy metal ions (Cu2+) determination in water environment. Photoelectrochemical selective sensing of trace amounts of Cu2+ was also discussed.
Co-reporter:Hui Xu, Jia Yan, Xiaojie She, Li Xu, Jiexiang Xia, Yuanguo Xu, Yanhua Song, Liying Huang and Huaming Li
Nanoscale 2014 vol. 6(Issue 3) pp:1406-1415
Publication Date(Web):22 Oct 2013
DOI:10.1039/C3NR04759H
Graphene-analogue nanostructures defined as a new kind of promising materials with unique electronic, surface and optical properties have received much attention in the fields of catalysis, energy storage, sensing and electronic devices. Due to the distinctive structure characteristics of the graphene-analogue materials, they brought novel and amazing properties. Herein, graphene-analogue carbon nitride (GA-C3N4) was synthesized by high-yield, large-scale thermal exfoliation from the graphitic C3N4-based intercalation compound. Graphene-analogue carbon nitride exhibited 2D thin-layer structure with 6–9 atomic thickness, a high specific surface area of 30.1 m2 g−1, increased photocurrent responses and improved electron transport ability, which could give rise to enhancing the photocatalytic activity and stability. The graphene-analogue carbon nitride had a new features that could make it suitable as a sensor for Cu2+ determination. So GA-C3N4 is a new but promising candidate for heavy metal ions (Cu2+) determination in water environment. The photocatalytic mechanism and photoelectrochemical selective sensing of Cu2+ were also discussed.
Co-reporter:Jun Xiong, Wenshuai Zhu, Wenjing Ding, Peng Wang, Yanhong Chao, Ming Zhang, Fengxia Zhu and Huaming Li
RSC Advances 2014 vol. 4(Issue 76) pp:40588-40594
Publication Date(Web):11 Aug 2014
DOI:10.1039/C4RA05260A
The synthesis of mesoporous materials with metal species highly dispersed in the mesoporous channels, and which still retain a high surface area and pore volume, is a considerable challenge. In the present study, however, the synthesis of mesoporous silica, assisted by metal-based ionic liquids, has achieved this goal. The metal-containing mesoporous silica materials were synthesized using a variety of metal-based ionic liquids as templates and metal sources, including [C16mim]Cl/CuCl2, 2[C16mim]Cl/CuCl2, 3[C16mim]Cl/FeCl3, [C16mim]Cl/MnCl2, and [C16mim]Cl/NiCl2. The mesoporous materials obtained were characterized by X-ray diffraction, transmission electron microscopy and nitrogen adsorption–desorption isotherms, and the results confirmed that they possessed a well-ordered hexagonal structure, a high surface area (∼1400 m2 g−1), a large pore volume (∼0.8 cm3 g−1), and an accessible mesoporous structure. The metal species were highly dispersed throughout the mesoporous framework. The results indicate that these ionic liquid-functionalized metal-containing mesoporous silica materials are suitable adsorbents for the removal of dibenzothiophene from fuels.
Co-reporter:Hui Xu, Yongxiu Song, Yanhua Song, Jiaxiang Zhu, Tingting Zhu, Chengbao Liu, Dexiang Zhao, Qi Zhang and Huaming Li
RSC Advances 2014 vol. 4(Issue 65) pp:34539-34547
Publication Date(Web):30 Jun 2014
DOI:10.1039/C4RA03443K
A facile, simple method was developed for the synthesis of g-C3N4/Ag2CO3 at room temperature. The samples were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and Fourier transformed infrared (FT-IR) spectroscopy. The photocatalytic activity of g-C3N4/Ag2CO3 composites for the photo-degradation of methyl orange (MO) was much higher than that of the pure Ag2CO3. The kinetics of the g-C3N4/Ag2CO3 composites were proposed. The electrochemical impedance spectroscopy of g-C3N4/Ag2CO3 composites and a series of radical trapping experiment were also carried out to explore the possible photocatalytic mechanism. The results indicated that the enhanced photocatalytic activity of g-C3N4/Ag2CO3 composites under visible light irradiation was attributed to the formed heterostructure between g-C3N4 and Ag2CO3, which was beneficial to the separation of the photoinduced electron–hole pairs.
Co-reporter:Hui Xu, Jiaxiang Zhu, Yongxiu Song, Wenkai Zhao, Yuanguo Xu, Yanhua Song, Haiyan Ji and Huaming Li
RSC Advances 2014 vol. 4(Issue 18) pp:9139-9147
Publication Date(Web):10 Jan 2014
DOI:10.1039/C3RA46111D
The AgBr/Ag2CO3 composite was synthesized by an ion-exchange reaction. The physical and chemical properties of the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), diffuse-reflection spectra (DRS) and photocurrent techniques. The photocatalytic performance of the samples was evaluated by photocatalytic oxidation of methylene blue (MB) dye under visible-light irradiation. The XRD, SEM-EDS, TEM, and XPS analyses indicated that the heterojunction structure had been obtained. The results indicated that the AgBr/Ag2CO3 heterojunction had exhibited a much higher photocatalytic activity than the pure Ag2CO3. The enhancement of photocatalytic activity was related to the efficient separation of electron–hole pairs because of the stagger band potentials between AgBr and Ag2CO3.
Co-reporter:Yeping Li, Jian Zhan, Liying Huang, Hui Xu, Huaming Li, Rongxian Zhang and Shilong Wu
RSC Advances 2014 vol. 4(Issue 23) pp:11831-11839
Publication Date(Web):03 Feb 2014
DOI:10.1039/C3RA46818F
Novel bentonite/g-C3N4 composite photocatalysts were synthesized through a conventional calcination method and systematically characterized by thermogravimetric analysis (TG), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV-vis diffuse reflection spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) and photocurrent–time measurement (PT). The optimal sample bentonite/g-C3N4 (5.4%) composite shows an enhanced photocurrent value (about 8 times as high as that of g-C3N4) under visible light irradiation and high efficiency for the degradation of methylene blue (the photoreaction kinetics constant value is about 2.5 times that of g-C3N4) under visible light. Results show the improved photoactivity is mainly attributed to the electrostatic interaction between g-C3N4 and negatively charged bentonite, this leads to the efficient migration of the photogenerated electrons and holes of g-C3N4. This study reports an inexpensive and environmentally friendly photocatalyst for pollution degradation and prospective photoelectric materials.
Co-reporter:Jiajia Chen, Jiaxiang Zhu, Zulin Da, Hui Xu, Jia Yan, Haiyan Ji, Huoming Shu, Huaming Li
Applied Surface Science 2014 Volume 313() pp:1-9
Publication Date(Web):15 September 2014
DOI:10.1016/j.apsusc.2014.04.109
Highlights
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Graphene-like BN/AgBr photocatalysts were prepared by facile water bath method.
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The photoactivity and stability of AgBr could be improved by coupling with BN.
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The synergetic effect of BN and AgBr were beneficial for enhancing photoactivity.
Co-reporter:Wei Jiang, Wenshuai Zhu, Yonghui Chang, Huaming Li, Yanhong Chao, Jun Xiong, Hui Liu, and Sheng Yin
Energy & Fuels 2014 Volume 28(Issue 4) pp:2754
Publication Date(Web):March 24, 2014
DOI:10.1021/ef500082y
A series of organic hexacyanoferrates were synthesized and employed as catalysts in ionic liquids (ILs) for catalytic oxidation of dibenzothiophene (DBT), benzothiophene (BT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT). High activity was achieved using 1-butyl-3-methylimidazolium hexacyanoferrate ([C4mim]3Fe(CN)6) as a catalyst and 1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim]BF4) as an extractant in the presence of H2O2 under mild conditions. It was interesting to find that the concentration of H2O2 had a significant influence on desulfurization efficiency. The sulfur removal was 76.3% with 30 wt % H2O2 as an oxidant, while it could reach 97.9% with 7.5 wt % H2O2. Electron spin resonance (ESR) spectroscopy measurements gave the evidence that the active oxygen species O2• – was generated in the catalytic oxidative desulfurization process, and gas chromatography–mass spectrometry (GC–MS) analysis indicated that the sulfur compounds were oxidized to the corresponding sulfones. The influence factors, such as reaction temperature, time, concentration, and dosage of H2O2, amount of catalyst, catalytic system recycling, and different sulfur-containing compounds, were investigated. The kinetic investigations showed that oxidation of sulfur compounds presented a pseudo-first-order kinetic. Under the optimal conditions, the catalytic system could be recycled at least 4 times without a remarkable decrease in activity.
Co-reporter:Jun Xiong, Wenshuai Zhu, Wenjing Ding, Lei Yang, Yanhong Chao, Hongping Li, Fengxia Zhu, and Huaming Li
Industrial & Engineering Chemistry Research 2014 Volume 53(Issue 51) pp:19895-19904
Publication Date(Web):November 26, 2014
DOI:10.1021/ie503322a
A heterogeneous catalyst system was synthesized by immobilizing phosphotungstic acid on ionic liquid-modified mesoporous silica SBA-15 and applied in oxidative desulfurization. Structure and properties of catalyst were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the contact angle. The results demonstrated that the synthesized catalyst possessed ordered mesopore structure and high special surface area. Due to the introduction of imidazole-based ionic liquid, the catalyst exhibited good wettability for model oil, which had significant contribution to desulfurization activity. Both DBT and 4,6-DMDBT could be removed completely at mild conditions (60 °C, 40 min). The removal of BT also can reach 81.3% within 60 min. Furthermore, the catalyst was recovered and reused in four reaction runs with a slight decrease in activity.
Co-reporter:Teng Zhou, Yuanguo Xu, Hui Xu, Hefei Wang, Zulin Da, Shuquan Huang, Haiyan Ji, Huaming Li
Ceramics International 2014 Volume 40(Issue 7) pp:9293-9301
Publication Date(Web):August 2014
DOI:10.1016/j.ceramint.2014.01.152
The Ag/AgCl/g-C3N4 composites were prepared by in situ oxidation process. During the process, the prefabricated Ag nanoparticles well dispersed on the surface of g-C3N4 employed as a template and oxidized by FeCl3 to form the Ag/AgCl core–shell structure. The resultant samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (IR) spectroscopy and UV–vis diffuse-reflection spectra (DRS). As a kind of visible-light-driven plasmonic photocatalysts, the Ag/AgCl/g-C3N4 with the Ag/AgCl amount of 2.7 at% achieved the best photocatalytic activity for the methyl orange (MO) dye degradation. The photocatalytic degradation rate was 6.77 and 6.27 times as that of the g-C3N4 and Ag/g-C3N4 composites. The results indicated that the cooperative or synergistic effects between Ag/AgCl and g-C3N4 was existed which facilitated the separation of photo-induced electron–hole pairs and enhanced the photoactivity. Based on the results, a possible visible-light photocatalytic degradation mechanism was also discussed.
Co-reporter:Changhua Song;Hui Liu;Yuan Li;Shuai Ge;Hongwei Wang;Wenshuai Zhu;Yonghui Chang;Changri Han
Chinese Journal of Chemistry 2014 Volume 32( Issue 5) pp:434-442
Publication Date(Web):
DOI:10.1002/cjoc.201400054
Abstract
A series of metal-Al2O3 catalysts were prepared simply by the conventional impregnation with Al2O3 and metal chlorides, which were applied to the dehydration of fructose to 5-hydroxymethylfurfural (HMF). An agreeable HMF yield of 93.1% was achieved from fructose at mild conditions (100°C and 40 min) when employing Cr(III)-Al2O3 as catalyst in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl). The Cr(III)-Al2O3 catalyst was characterized via XRD, DRS and Raman spectra and the results clarified the interaction between the Cr(III) and the alumina support. Meanwhile, the reaction solvents ([Bmim]Cl) collected after 1st reaction run and 5th reaction run were analyzed by ICP-OES and LC-ITMS and the results confirmed that no Cr(III) ion was dropped off from the alumina support during the fructose dehydration. Notably, Cr(III)-Al2O3 catalyst had an excellent catalytic performance for glucose and sucrose and the HMF yields were reached to 73.7% and 84.1% at 120°C for 60 min, respectively. Furthermore, the system of Cr(III)-Al2O3 and [Bmim]Cl exhibited a constant stability and activity at 100°C for 40 min and a favorable HMF yield was maintained after ten recycles.
Co-reporter:Wenshuai Zhu;Yehai Xu;Bilian Dai
Korean Journal of Chemical Engineering 2014 Volume 31( Issue 2) pp:211-217
Publication Date(Web):2014 February
DOI:10.1007/s11814-013-0224-3
Three types of TiO2 were synthesized by a hydrolysis and calcination method. The catalysts were characterized by X-ray powder diffraction (XRD), diffuse reflectance spectrum (DRS), Raman spectra, and X-ray photoelectron spectroscopy (XPS). The XRD and Raman spectra indicated that amorphous TiO2 was successfully obtained at 100 °C. The results indicated that amorphous TiO2 achieved the highest efficiency of desulfurization. The photocatalytic oxidation of dibenzothiophene (DBT), benzothiophene (BT), 4,6-dimethyldibenzothiophene (4,6-DMDBT) and dodecanethiol (RSH) in model oil was studied at room temperature (30 °C) with three catalysts. The system contained amorphous TiO2, H2O2, and [Bmim]BF4 ionic liquid, ultraviolet (UV), which played vitally important roles in the photocatalytic oxidative desulfurization. Especially, the molar ratio of H2O2 and sulfur (O/S) was only 2: 1, which corresponded to the stoichiometric reaction. The sulfur removal of DBT-containing model oil with amorphous TiO2 could reach 96.6%, which was apparently superior to a system with anatase TiO2 (23.6%) or with anatase — rutile TiO2 (18.2%). The system could be recycled seven times without a signicant decrease in photocatalytic activity.
Co-reporter:Qingqing Gu, Wenshuai Zhu, Suhang Xun, Yonghui Chang, Jun Xiong, Ming Zhang, Wei Jiang, Fengxia Zhu, Huaming Li
Fuel 2014 Volume 117(Part A) pp:667-673
Publication Date(Web):30 January 2014
DOI:10.1016/j.fuel.2013.08.082
•W-mesoporous silicas were synthesized by functional IL [(n-C8H17)3NCH3]2W2O11.•The functional IL acted as template and W precursors during the synthesis process.•W species were highly dispersed into the mesoporous silica.•The catalysts showed good catalytic performance and reusability.A series of W-containing mesoporous silicas with different calcination temperatures were in situ synthesized by using [(n-C8H17)3NCH3]2W2O11 not merely as a novel template but also the W precursors. The catalysts were characterized by N2 adsorption–desorption, XRD, XPS, HRTEM, EDS, ICP, FTIR, and UV–vis DRS analysis. The N2 adsorption–desorption and HRTEM results indicated that these catalysts possessed mesoporous structure with relatively uniform pores and large internal surface areas. The XRD, ICP and HRTEM results indicated that the W species were highly dispersed on the surface and into the mesoporous silicas matrix. The catalysts also showed excellent catalytic performance on the removal of refractory bulky molecule sulfur compounds from the model oil with H2O2. Based on the removal of DBT in the model oil, the optimal calcination temperature of the catalysts is 450 °C. The catalytic activity of different sulfur-containing substrates was also investigated. After 8-times recycling, the sulfur removal could still reach 99.2% without any significant decrease.Graphical abstractA series of W-containing mesoporous silicas were designed, prepared and evaluated as the catalysts of oxidative desulfurization.
Co-reporter:Wei Jiang, Wenshuai Zhu, Huaming Li, Yanhong Chao, Suhang Xun, Yonghui Chang, Hui Liu, Zhen Zhao
Journal of Molecular Catalysis A: Chemical 2014 Volume 382() pp:8-14
Publication Date(Web):February 2014
DOI:10.1016/j.molcata.2013.10.017
•Several Fenton-like catalysts were synthesized and characterized systematically.•Deep desulfurization can be obtained in both hydrophilic IL and hydrophobic IL.•The oxidative desulfurization mechanism was studied by ESR spin-traping technique.•The oxidized products could be determined by GC–MS.Various Fenton-like catalysts prepared by choline chloride (ChCl) and metal salts (FeCl3, ZnCl2, SnCl2) were characterized by FT-IR, UV–vis, Raman, ESI-MS and elemental analysis. High desulfurization efficiency of dibenzothiophene (DBT) could be obtained not only in hydrophilic ionic liquid (IL) [Bmim]BF4 (94.9%) but also in hydrophobic IL [Omim]BF4 (97.2%) by using ChFeCl4 as a catalyst under mild conditions. ESR measurements could give the evidence that the active oxygen species generated by ChFeCl4 and H2O2 in IL were involved in the catalytic oxidation of DBT. The influential factors, including reaction time, temperature, catalyst dosage, and O/S (H2O2/DBT) molar ratio, were investigated in detail to estimate the optimal conditions for the desulfurization system in [Omim]BF4. The aromatic sulfur compounds, DBT, benzothiophene (BT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT), could be oxidized to the corresponding sulfones, which were detected by GC–MS. Moreover, the catalytic system containing IL and catalyst could be easily separated from oil and could be recycled at least five times without a significant decrease on removal of DBT.Dibenzothiophene (DBT) in model oil was first extracted into IL phase and oxidized to the corresponding sulfone by O2−, which was generated by ChFeCl4 upon interaction with H2O2 in IL.
Co-reporter:Wenshuai Zhu, Guopeng Zhu, Huaming Li, Yanhong Chao, Ming Zhang, Daolin Du, Qian Wang, Zhen Zhao
Fuel Processing Technology 2013 Volume 106() pp:70-76
Publication Date(Web):February 2013
DOI:10.1016/j.fuproc.2012.07.003
Surfactant-type polyoxometalate-based ionic liquids (SPILs), such as [(n-C8H17)3NCH3]3{PO4[MoO(O2)2]4}, [(n-C12H25)3NCH3]3{PO4[MoO(O2)2]4}, [(n-C8H17)3NCH3]3{PO4[WO(O2)2]4} and [(n-C12H25)3NCH3]3{PO4[WO(O2)2]4} have been investigated on their oxidative desulfurization. SPILs were very promising for the desulfurization of DBT in the model oil using H2O2 as the oxidant. Supposed mechanism and kinetics studies on the catalytic avtivity of SPIL [(n-C8H17)3NCH3]3{PO4[MoO(O2)2]4} revealed that the oxidative desulfurization of organosulfur compounds could present a pseudo first-order kinetic. The reaction rate constant and half-life of DBT oxidation were calculated. Moreover, the catalytic activity for other sulfur-containing compounds increased in the order BT < 4, 6-DMDBT < DBT. There is little change for the oxidative desulfurization efficiency of SPIL after 8 recycles. And this work offers an alternative for oxidative desulfurization of actual prehydrotreated fuel as well.Highlights► SPILs were designed based on the quaternary ammonium cations pairing with polyoxometalates anions. ► SPIL not only acted as an extractant but also served as a catalyst. ► The mechanism and kinetic of oxidation of DBT were proposed. ► SPILs can deeply remove refractory organosulfur compounds in both model oil and actual fuel.
Co-reporter:Yuanguo Xu, Hui Xu, Lei Wang, Jia Yan, Huaming Li, Yanhua Song, Liying Huang and Guobin Cai
Dalton Transactions 2013 vol. 42(Issue 21) pp:7604-7613
Publication Date(Web):28 Feb 2013
DOI:10.1039/C3DT32871F
A novel, multi-walled carbon nanotubes (CNT) modified white C3N4 composite (CNT/white C3N4) with enhanced visible-light-response photoactivity was prepared. The white C3N4 and CNT combined together and formed the CNT/white C3N4 composite due to electrostatically-driven self-assembly with the hydrothermal method. The as-prepared white C3N4 and CNT/white C3N4 composite photocatalyst were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-vis absorption spectra, X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). The photoelectrochemical i–t curves were tested using several on–off cycles of light irradiation. The photoactivity of the catalysts was evaluated by degrading methylene blue (MB) dye solution. The results showed that the photoactivity for the degradation of MB solution was in the following order: CNT/white C3N4 composite > C3N4 > the white C3N4. The photoactivity of the CNT/white C3N4 composite was 66.5% and 34.5% higher than that of the white C3N4 sample and that of the C3N4 at 1.5 h, respectively. The degradation rate of the CNT/white C3N4 photocatalyst was almost 8.1 times as high as that of the white C3N4. The results indicated that CNT played an important role, which led to the efficient separation of the photo-generated charge carriers. The reason why the photoactivity of the CNT/white C3N4 was much higher than that of C3N4 and the white C3N4 was discussed. A possible mechanism of CNT on the enhancement of composites' visible light performance was also proposed.
Co-reporter:Yuanguo Xu, Hui Xu, Jia Yan, Huaming Li, Liying Huang, Qi Zhang, Chuanjing Huang and Huilin Wan
Physical Chemistry Chemical Physics 2013 vol. 15(Issue 16) pp:5821-5830
Publication Date(Web):11 Feb 2013
DOI:10.1039/C3CP44104K
A facile, one-step synthesis of carbon nanotube (CNT)-loaded Ag/AgBr is reported. The as-prepared samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), UV/Vis absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, photoluminescence (PL) spectroscopy and electrochemical impedance spectroscopy (EIS). The CNT/Ag/AgBr composite exhibited much higher photocatalytic activity than pure Ag/AgBr in degrading methyl orange (MO) dye solution. The loading amount of CNT had a significant influence on the photoactivity of the CNT/Ag/AgBr composite. When the CNT loading amount was 1.4 at%, the hybrid material showed the highest photocatalytic ability. The result showed that a small amount of CNT was beneficial for photo-generated electron transfer, which could enhance the photoactivity of CNT/Ag/AgBr. The degradation dye solution was tested by liquid chromatography/mass spectrometry (LC/MS) and total organic carbon (TOC) analysis. Based on the results, the structure of the synthesized CNT/Ag/AgBr hybrid material was verified and the possible degradation path of the MO dye was proposed. A possible visible-light photocatalytic degradation mechanism was also discussed.
Co-reporter:Liying Huang, Hui Xu, Rongxian Zhang, Xiaonong Cheng, Jiexiang Xia, Yuanguo Xu, Huaming Li
Applied Surface Science 2013 Volume 283() pp:25-32
Publication Date(Web):15 October 2013
DOI:10.1016/j.apsusc.2013.05.106
Highlights
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Visible-light driven g-C3N4/MoO3 photocatalyst has been synthesized.
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The optimal photoactivity of g-C3N4/MoO3 is 4.2 times as high as that of MoO3.
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The heterojunction is favorable to improve the separation of electron and hole.
Co-reporter:Wenshuai Zhu, Yuxiao Ding, Huaming Li, Jiao Qin, Yanhong Chao, Jun Xiong, Yehai Xu and Hui Liu
RSC Advances 2013 vol. 3(Issue 12) pp:3893-3898
Publication Date(Web):07 Feb 2013
DOI:10.1039/C3RA23274C
A tungsten-containing task-specific ionic liquid (IL) [(C6H13)3PC14H29]2W6O19 was synthesized and applied in the desulfurization process of a dibenzothiophene-containing model oil with aqueous hydrogen peroxide. In the desulfurization process, a novel aqueous hydrogen peroxide-in-IL emulsion catalytic system was found. The task-specific IL not only acted as extraction media for the organo-sulfur compounds and served as a catalyst for the hydrogen peroxide but also provided an oxidation micro-environment for the conversion from sulfur compounds to sulfones by forming IL emulsions. The self-emulsifiable IL played two roles in the emulsification process: the surfactant and the dispersion medium.
Co-reporter:Wenshuai Zhu, Peiwen Wu, Yanhong Chao, Huaming Li, Fang Zou, Suhang Xun, Fengxia Zhu, and Zhen Zhao
Industrial & Engineering Chemistry Research 2013 Volume 52(Issue 49) pp:17399
Publication Date(Web):November 4, 2013
DOI:10.1021/ie402513x
A novel reaction-controlled foam-type catalyst has been designed by pairing 1-hexadecyl-3-methyl-imidazolium cation with peroxomolybdate anion. This catalyst switched from the powder to the foam-type active species, exhibiting high catalytic activity in the oxidative desulfurization process. After the reaction was finished, the foam became brittle and returned to powder form, which could be easily separated and reused. Reasons for this change were detailed by experiments. The removal of dibenzothiophene (DBT) could reach 98.4% under the optimal conditions of n(DBT)/n(catalyst)/n(H2O2) = 30:1:180, at 50 °C for 1 h. The catalyst could be recycled six times, and the sulfur removal still remained to be about 93.9%.
Co-reporter:Jiexiang Xia, Jing Zhang, Sheng Yin, Huaming Li, Hui Xu, Li Xu, Qi Zhang
Journal of Physics and Chemistry of Solids 2013 Volume 74(Issue 2) pp:298-304
Publication Date(Web):February 2013
DOI:10.1016/j.jpcs.2012.10.002
BiOCl uniform flower-like microspheres and porous nanospheres structures have been successfully synthesized through a one-pot ethylene glycol (EG)-assisted solvothermal process in the presence of reactable ionic liquid 1-hexadecy-3-methylimidazolium chloride ([C16mim]Cl) and [C16mim]Cl–PVP composite system. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and UV–vis diffuse reflectance spectroscopy (DRS). During the reaction process, the ionic liquid acted not only as the solvent and the template, but also as a Cl source for the fabrication of BiOCl microspheres. The effect of the cation alkyl chain length of ionic liquids on morphology and optical absorption properties was investigated and is discussed in detail. In addition, the photocatalytic activity of the BiOCl samples was evaluated by rhodamine B (RhB) dye degradation under visible-light irradiation. It was found that BiOCl porous nanospheres exhibited higher photocatalytic activity than that of the samples prepared with conventional method and TiO2 (Degussa, P25).Highlights► Flower-like and porous BiOCl materials have been synthesized with ionic liquid [C16mim]Cl. ► Ionic liquid [C16mim]Cl played the role of solvent, reactant and template simultaneously. ► Porous BiOCl catalyst showed efficient degradation of RhB under the visible light irradiation.
Co-reporter:Yuanguo Xu, Hui Xu, Jia Yan, Huaming Li, Liying Huang, Jiexiang Xia, Sheng Yin, Huoming Shu
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2013 Volume 436() pp:474-483
Publication Date(Web):5 September 2013
DOI:10.1016/j.colsurfa.2013.06.005
•A plasmonic photocatalyst Ag/AgBr/g-C3N4 nanocomposite was synthesized via a solvothermal method.•The Ag/AgBr/g-C3N4 showed enhanced photoactivity than g-C3N4 under visible light.•Highly dispersed Ag/AgBr anchored on the surface of g-C3N4 played an important role.•A possible reaction mechanism was proposed.A plasmonic photocatalyst of Ag/AgBr/g-C3N4 was prepared by a solvothermal method. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV–vis absorption spectra (in the diffuse reflectance spectra mode), photoluminescence (PL) emission spectra, and infrared (IR) spectra have been employed to determine the structure, morphology and optical property of the as-prepared Ag/AgBr/g-C3N4 composite. The interaction between Ag/AgBr and g-C3N4 has been observed by X-ray photoemission spectroscopy (XPS) analysis, and which is facile to the electron transfer between Ag/AgBr and g-C3N4 and result in the enhancing photocatalytic activity of Ag/AgBr/g-C3N4 composite. The Ag/AgBr/g-C3N4 showed much higher photoactivity than the simple mixing of Ag/AgBr and g-C3N4 with the same amount. Besides, the high dispersion of Ag/AgBr anchored on the surface of g-C3N4 was also assumed to be responsible for the enhanced activity and good recycling ability. The 17.8 at.% Ag/AgBr/g-C3N4 showed the highest photoactivity, the degradation rate constant of 17.8 at.% Ag/AgBr/g-C3N4 was as high as 18.3 times to that of the pure g-C3N4. The relationship between the photocatalytic activity and the structure of Ag/AgBr/g-C3N4 hybrid materials was discussed and the possible reaction mechanism was proposed.Ag/AgBr/g-C3N4 photocatalyst with enhanced photocatalytic activity was designed and fabricated.
Co-reporter:Yuanguo Xu, Hui Xu, Huaming Li, Jia Yan, Jiexiang Xia, Sheng Yin, Qi Zhang
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2013 Volume 416() pp:80-85
Publication Date(Web):5 January 2013
DOI:10.1016/j.colsurfa.2012.07.014
Ag@AgCl core–shell nanocomposite was synthesized by using [Bmim]FeCl4 IL etching Ag nanowires into Ag@AgCl in solution at room temperature. The obtained samples exhibited highly visible-light photocatalytic ability for the degradation of methyl orange and 4-chlorophenol in water solution. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of Ag and AgCl crystals. Scanning electron microscopy (SEM) images and X-ray energy-dispersive spectroscopy (EDS) of the samples revealed that AgCl nanoparticles (NPs) formed on the surface of Ag nanowires. UV–vis spectroscopy showed that Ag@AgCl core–shell structure enhanced its absorption in the visible-light region. The results showed that the absorption ability of Ag@AgCl was related to the change of Ag@AgCl. The absorption ability of the samples increased with the increasing etching time, and the enhancing photocatalytic ability was due to the increasing plasmonic absorbance of the photocatalysts. The effect of the etching time on the photocatalyst activity was studied, and the reaction mechanism was proposed.Graphical abstractThis is the first report investigates Ag etched into Ag@AgCl by [Bmim]FeCl4 IL and its photocatalytic activity. The photocatalytic activity of the as-prepared materials had been investigated by the degradation of methyl orange and 4-chlorophenol under visible-light irradiation. The influence of the etching time on the photocatalytic activity of the sample was studied. We deduced the formation process of the catalyst and discussed the mechanism of the reaction process based on X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible diffused reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS).Highlights► There was no report investigate Ag@AgCl core-shell structure synthesized by [Bmim]FeCl4 IL. ► The photocatalytic activity of the catalysts is greatly depends on the etching time. ► The photocatalytic ability of the catalyst enhanced with the increasing of the plasmon absorption. ► The possible photocatalytic mechanism was proposed.
Co-reporter:Jing Zhang, Jiexiang Xia, Sheng Yin, Huaming Li, Hui Xu, Minqiang He, Liying Huang, Qi Zhang
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2013 420() pp: 89-95
Publication Date(Web):
DOI:10.1016/j.colsurfa.2012.11.054
Co-reporter:Hui Xu, Yuanguo Xu, Huaming Li, Jiexiang Xia, Jun Xiong, Sheng Yin, Chuanjing Huang and Huilin Wan
Dalton Transactions 2012 vol. 41(Issue 12) pp:3387-3394
Publication Date(Web):06 Feb 2012
DOI:10.1039/C2DT11969B
A novel heterojunction AgBr/BiPO4 photocatalyst was synthesized with the hydrothermal method. The photocatalyst was characterized by X-Ray powder Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectrometry (EDS), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectrscopy (XPS) and Diffuse Reflectance Spectroscopy (DRS). The XRD, SEM-EDS, TEM and XPS analyses indicated that the heterojunction structure formed during the process of hydrothermal treatment. The photocatalytic activity of the photocatalysts was evaluated by degradation of methylene blue dye (MB). The results indicated that the AgBr/BiPO4 heterojunction exhibited a much higher photocatalytic activity than the pure BiPO4. The mechanism of the enhancing AgBr/BiPO4 heterojunction's photocatalytic activity was discussed. It was also found that the photocatalytic degradation of MB over AgBr/BiPO4 heterojunction photocatalysts followed the pseudo-first-order reaction model.
Co-reporter:Wenshuai Zhu, Jingtong Zhang, Huaming Li, Yanhong Chao, Wei Jiang, Sheng Yin and Hui Liu
RSC Advances 2012 vol. 2(Issue 2) pp:658-664
Publication Date(Web):16 Nov 2011
DOI:10.1039/C1RA00163A
The extraction desulfurization (EDS) and extraction combined with oxidation desulfurization (EODS) for the removal of dibenzothiophene (DBT), benzothiophene (BT), and 4,6-dimethyldibenzothiphene (4,6-DMDBT) in a model oil were carried out in Fenton-like ionic liquids, such as [Et3NHCl]FeCl3, [Et3NHCl]CuCl2, [Et3NHCl]ZnCl2, [Et3NHCl]CoCl2, [Et3NHCl]SnCl2 and [Et3NHCl]CrCl3. The deep desulfurization could be achieved in [Et3NHCl]FeCl3 for only 5 min at room temperature. The reaction conditions such as temperature, the molar ratio of H2O2 and DBT and the amount of ionic liquid (IL) were investigated in the EODS system. By controlling the way of adding H2O2 into the desulfurization system, the sulfur content in the model oil could decrease from 500 mg L−1 to less than 10 mg L−1 at the IL/oil volume of 1:5. The oxidation reactivity of the different sulfur-containing compounds was found to be in the order of DBT > BT > 4,6-DMDBT. Moreover, the EODS system could be recycled ten times with a slight decrease in activity to model oil. EODS process was applied to prehydrotreated gasoline and the sulfur content could decrease from 150 to 15 mg L−1 after two rounds of reaction.
Co-reporter:Hui Xu;Yanhua Song;Ling Liu;Yuanguo Xu;Jiexiang Xia;Xiangyang Wu;Shuowei Zhao
Journal of Chemical Technology and Biotechnology 2012 Volume 87( Issue 12) pp:1626-1633
Publication Date(Web):
DOI:10.1002/jctb.3841
Abstract
BACKGROUND: Plasmonic photocatalysts have attracted considerable attention because of their applications in the degradation of organic pollutants. In order to enhance the stability of AgX photocatalyst, Ag/AgCl, Ag/AgBr/WO3, and Ag@AgCl/RGO were developed. Results implied that silver halides could maintain stability if the metal Ag was well dispersed on the silver halide particles and could display high catalytic activity.
RESULTS: PVP acted as a structure-directing agent, and a reducing reagent in the reaction. Results show that Ag–AgBr delivered a much higher photocatalytic activity than AgBr and Ag–AgCl. The high photocatalytic activity of the Ag–AgBr composites can be attributed to the presence of metal Ag and the smaller particle size of the samples. The photocatalytic reaction followed first-order kinetics. The rate constant k for the degradation of MO by Ag–AgBr was 2 and 18 times higher than that of AgBr and Ag–AgCl, respectively.
CONCLUSIONS: The MO degradation efficiency of Ag–AgBr was 94% after 10 min. After 5 cycles of repeatability tests, the degradation efficiency of MO still remained at 90%. The high photocatalytic activity of the Ag–AgBr composites can be attributed to the presence of metal Ag and the smaller particle size of the samples. Copyright © 2012 Society of Chemical Industry
Co-reporter:Ling Liu, Hui Xu, Huaming Li, Yuanguo Xu, Jiexiang Xia, Sheng Yin
Journal of Physics and Chemistry of Solids 2012 Volume 73(Issue 4) pp:523-529
Publication Date(Web):April 2012
DOI:10.1016/j.jpcs.2011.11.034
AgBr photocatalysts were prepared with the 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br) reactable ionic liquid at different temperatures by one-step hydrothermal method, in which the ionic liquid acted as a precursor and a template to control the size of AgBr crystal. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), the Brunauer–Emmett–Teller (BET) surface area and diffuse reflectance spectroscopy (DRS). Methyl orange (MO) dye was chosen as a model pollutant to investigate the photocatalytic activity and the stability of the samples under visible light irradiation. The results indicated that the AgBr photocatalysts showed high efficiency in the degradation of MO under visible light irradiation. The kinetic property of the reaction followed the first-order reaction model. During the photocatalytic degradation reaction, AgBr was transformed to the Ag0/AgBr composite. However, the photocatalytic efficiency was still high and the photocatalytic activity was stable. The possible photocatalytic mechanism of the photocatalysts was also eventually proposed.Highlights► The ionic liquid acted as a precursor and template in the synthesis of AgBr. ► The size and light absorption ability of AgBr affected the photocatalytic activity. ► AgBr photocatalyst showed high and good stable efficiency after five cycles.
Co-reporter:Sheng Feng, Hui Xu, Ling Liu, Yanhua Song, Huaming Li, Yuanguo Xu, Jiexiang Xia, Sheng Yin, Jia Yan
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2012 410() pp: 23-30
Publication Date(Web):
DOI:10.1016/j.colsurfa.2012.06.009
Co-reporter:Yuxiao Ding, Wenshuai Zhu, Huaming Li, Wei Jiang, Ming Zhang, Yuqing Duan and Yonghui Chang
Green Chemistry 2011 vol. 13(Issue 5) pp:1210-1216
Publication Date(Web):21 Mar 2011
DOI:10.1039/C0GC00787K
Three hexatungstates ([(C4H9)3NCH3]2W6O19, [(C8H17)3NCH3]2W6O19, [(C12H25)3NCH3]2W6O19) have been synthesized and characterized. The hexatungstates were dissolved in the hydrophobic 1-octyl-3-methylimidazolium hexafluorophosphoric ([Omim]PF6) ionic liquid (IL) forming a water-in-IL emulsion system with aqueous hydrogen peroxide. Catalytic oxidation of sulfur-containing model oil and real gasoline was studied under different conditions with this system. The multiphase reaction of the new IL emulsion system made for easy separation and exhibited good recycleability. As a stable macrocosm, the separated catalytic system could be directly added to fresh oil and H2O2 for the next run without any treatment and after recycling 15 times, the sulfur removal could still reach a high level without any decrease. The supposed mechanism is given to show the superiority of the new emulsion catalytic system.
Co-reporter:Hui Xu, Huaming Li, Jiexiang Xia, Sheng Yin, Zhijun Luo, Ling Liu, and Li Xu
ACS Applied Materials & Interfaces 2011 Volume 3(Issue 1) pp:22
Publication Date(Web):December 28, 2010
DOI:10.1021/am100781n
Plasmonic photocatalyst Ag/AgCl was prepared by in situ hydrothermal method with the contribution of 1-octyl-3-methylimidazolium chloride ([Omim]Cl), in which the [Omim]Cl ionic liquid acted not only as a precursor but also as a reducing reagent in the process of formation of Ag0. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and thermogravimetric and differential scanning calorimetry (TG-DSC). The photocatalytic activity of the composites were evaluated by degradation of methyl orange (MO) under visible light irradiation. The experimental results showed that the high activity and stability of Ag/AgCl photocatalysts under visible-light irradiation were due to their localized surface plasmon resonance (LSPR). Based on the characterization of the structure and photocatalytic performance, the LSPR was determined by synergetic effect of many factors, such as particle size of metallic Ag, contents of the Ag0 nanoparticles, and the extent of metallic Ag dispersing. A photocatalytic mechanism of the Ag/AgCl photocatalyst was also proposed.Keywords: Ag/AgCl; Ionic liquid; Localized surface plasmon resonance; Plasmonic photocatalyst
Co-reporter:Jiexiang Xia, Sheng Yin, Huaming Li, Hui Xu, Li Xu and Yuanguo Xu
Dalton Transactions 2011 vol. 40(Issue 19) pp:5249-5258
Publication Date(Web):06 Apr 2011
DOI:10.1039/C0DT01511C
BiOBr uniform flower-like hollow microsphere and porous nanosphere structures have been successfully synthesized through a one-pot EG-assisted solvothermal process in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br). The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). Possible formation mechanism for the growth of hollow microspheres was discussed. During the reactive process, ionic liquid [C16mim]Br played the role of solvent, reactant and template at the same time. Moreover, the photocatalytic activities of BiOBr flower-like hollow and porous structures were evaluated on the degradation of rhodamine B (RhB) under visible light irradiation. The results assumed that BiOBr porous nanospheres sample showed much higher photocatalytic activity than the conventionally prepared sample and TiO2 (Degussa, P25). The relationship between the structure of the photocatalyst and the photocatalytic activities were also discussed in detail; it can be assumed that the enhanced photocatalytic activities of BiOBr materials could be ascribed to a synergistic effect, including high BET surface area, the energy band structure, the smaller particle size and light absorbance.
Co-reporter:Wenshuai Zhu, Wangli Huang, Huaming Li, Ming Zhang, Wei Jiang, Guangying Chen, Changri Han
Fuel Processing Technology 2011 Volume 92(Issue 10) pp:1842-1848
Publication Date(Web):October 2011
DOI:10.1016/j.fuproc.2011.04.030
In order to obtain the ultra low-sulfur diesel, deep desulfurization of diesel oil has become a vital subject of environmental catalysis studies. Extraction and catalytic oxidation desulfurization (ECODS) system is one of the most promising desulfurization processes. A series of Keggin-type POM-based ionic liquids hybrid materials [MIMPS]3PW12O40·2H2O (1-(3-sulfonic group) propyl-3-methyl imidazolium phosphotungstate), [Bmim]3PW12O40 (1-butyl 3-methyl imidazolium phosphotungstate), [Bmim]3PMo12O40 (1-butyl 3-methyl imidazolium phosphomolybdate) and [Bmim]4SiW12O40 (1-butyl-3-methyl imidazolium silicotungstate) have been developed in this study, and the reaction has performed using the POM-ILs materials as catalysts, H2O2 as oxidant, and ionic liquid (IL) as solvent. Through experimental evaluations, [MIMPS]3PW12O40·2H2O was found to be the best catalyst, with an S-removal of 100% at 30 °C for 1 h. The main factors affecting the process including temperature, catalyst dosage, and O/S (H2O2/DBT) molar ratio were investigated in detail. Under the optimal conditions, DBT (dibenzothiophene) and 4,6-DMDBT (4,6-dimethyl-dibenzothiophene) could achieve high desulfurization efficiency. Moreover, the reaction system also exhibited high activity in actual diesel oil, which could be reduced from 1113 ppm to 198 ppm. The reaction system could recycle 8-times with a slight decrease in activity.Research highlights► Several POM-based ILs were synthesized and characterized. ► New attempt with POM-based ILs as catalysts in removing DBT in fuels. ► High desulfurization was achieved in water-immiscible IL. ► Desulfurization differences among different POM-ILs catalysts have been explained.
Co-reporter:Hui Xu, Chengtang Liu, Huaming Li, Yuanguo Xu, Jiexiang Xia, Sheng Yin, Ling Liu, Xiangyang Wu
Journal of Alloys and Compounds 2011 Volume 509(Issue 37) pp:9157-9163
Publication Date(Web):15 September 2011
DOI:10.1016/j.jallcom.2011.06.100
A series of NaNbO3/ZnO heteronanostructures were synthesized with the hydrothermal method. Various characterization methods such as X-ray powder diffraction (XRD), scanning electronic microscope (SEM) and energy dispersive X-ray spectrometer (EDS), transmission electron microscope (TEM), X-ray photoelectron spectra (XPS) and diffuse reflectance spectra (DRS) were employed to investigate the structure, morphology and photocatalytic properties. The photocatalytic activity of the catalysts was evaluated by the degradation of methylene blue dye and the highest photocatalytic efficiency was observed when the content of NaNbO3 was 10 wt.%. The photocatalytic mechanism of the heterojunction was also discussed. The effective transformation of the photoexcited electron and holes restricted the recombination of charges, which was regarded as the main reason of the high photocatalytic activity.Highlights► There was no report to investigate the photocatalytic activity of NaNbO3/ZnO heterojunction. ► The relationship between the photocatalytic activity and the structural features of the prepared catalysts was investigated through a systematic characterization analysis. ► The possible photocatalytic mechanism was proposed.
Co-reporter:Li Xu;Jiexiang Xia, ;Henan Li;Kun Wang ;Sheng Yin
European Journal of Inorganic Chemistry 2011 Volume 2011( Issue 9) pp:1361-1365
Publication Date(Web):
DOI:10.1002/ejic.201001160
Abstract
Cu polyhedron-pattern nanostructures have been successfully synthesized in the presence of the ionic liquid (IL) 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br) under solvothermal conditions. The as-prepared samples were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared (FTIR) spectroscopy and diffuse reflectance spectroscopy (DRS). During the reaction process, the ionic liquid played an important role in controlling the morphology and size of the Cu polyhedron-pattern nanostructures. The results of FTIR spectroscopic analysis indicated that there was the ionic liquid [C16mim]Br on the surface of the Cu polyhedron-pattern nanostructures. Cu polyhedron-pattern nanostructures exhibited better thermal stability in air than Cu samples synthesized without ionic liquid at room temperature. In addition, the electrocatalytic activity of the Cu-modified electrodes towards glucose oxidation was investigated by cyclic voltammetry. The results clearly demonstrated that the unique morphology and small size of the Cu polyhedron-pattern nanostructures made them suitable for application as non-enzymatic glucose sensors. Simultaneously, the [C16mim]Br ionic liquid on the surface of the Cu polyhedron-pattern nanostructures had a significant impact on the electrocatalytic activity of Cu polyhedron-pattern nanostructures. Thus, electrodes modified with these Cu polyhedron-pattern nanostructures are promising for the future development of non-enzymatic glucose sensors.
Co-reporter:Yuanguo Xu, Hui Xu, Huaming Li, Jiexiang Xia, Chengtang Liu, Ling Liu
Journal of Alloys and Compounds 2011 Volume 509(Issue 7) pp:3286-3292
Publication Date(Web):17 February 2011
DOI:10.1016/j.jallcom.2010.11.193
A new composite photocatalyst Ag/AgCl/ZnO was fabricated by a two-step synthesis method under the hydrothermal condition. The sample was characterized by XRD, TG-DSC, SEM, TEM, DRS and XPS. The results showed that the samples were composed of Ag, AgCl and ZnO, and the particle size was in the range of 100 nm–1 μm. Methyl orange (MO) was used as a representative dye pollutant to evaluate the photocatalytic activity of Ag/AgCl/ZnO. The photocatalytic activity of Ag/AgCl/ZnO catalyst was higher than that of the pure ZnO catalyst. It was found that the Ag/AgCl/ZnO structure changed to Ag/ZnO gradually after several repeated experiments. However, the photocatalytic ability of the sample was not reduced. Finally, a possible photocatalytic mechanism was proposed.Research highlights▶ There was no report to investigate the photocatalytic activities of Ag/AgCl/ZnO. ▶ The catalyst changed in the reaction process (Ag/AgCl/ZnO to Ag/ZnO). ▶ The activity of the catalyst did not change after its structure changed. ▶ The possible photocatalytic mechanism was proposed.
Co-reporter:Wenshuai Zhu, Guopeng Zhu, Huaming Li, Yanhong Chao, Yonghui Chang, Guangying Chen, Changri Han
Journal of Molecular Catalysis A: Chemical 2011 Volume 347(1–2) pp:8-14
Publication Date(Web):1 August 2011
DOI:10.1016/j.molcata.2011.07.002
Metal-based surfactant-type ionic liquids (MSILs) methyltri-n-octylammonium peroxomolybdate [(CH3)N(n-C8H17)3]2Mo2O11 and peroxotungstate [(CH3)N(n-C8H17)3]2W2O11 were synthesized and characterized, which have been extended to new families and generations of functionalized ILs. Here the MSILs were applied in removal of sulfur-containing compounds with H2O2 and possessed of the character of reaction-induced self-separation catalysis. The effects of H2O2/DBT (molar ratio), oil/MSIL (mass ratio) and the agitation rate were studied to estimate the optimal conditions for the desulfurization system catalyzed by [(CH3)N(n-C8H17)3]2Mo2O11. The quaternary ammonium cation could transfer the catalytic active species to the aromatic sulfur compounds under the reaction conditions and higher oxidative reaction rate was achieved. Kinetic experiments revealed that the oxidative desulfurization reaction was in accordance with pseudo-first-order kinetics and the reaction rate constant and half-life were calculated. Furthermore, the oxidation reactivity of different substrates was in the following order: DBT > 4,6-DMDBT > BT. The MSIL [(CH3)N(n-C8H17)3]2Mo2O11 could be recycled for 10-times with a slight decrease in activity. [(CH3)N(n-C8H17)3]2Mo2O11 was also an efficient catalyst to remove the sulfur-containing compound in different solvents. Multiple reactions of oxidation desulfurization process were feasible and effective for prehydrotreated gasoline.Graphical abstractHighlights► MSILs were designed by pairing quaternary ammonium cation with polyoxometalate anions. ► [(CH3)N(n-C8H17)3]2Mo2O11 can be self-separated at the end of the reaction. ► For self-separation, [(CH3)N(n-C8H17)3]2Mo2O11 is convenient for recycle. ► MSILs can deeply remove refractory organosulfur in both model oil and prehydrotreated gasoline.
Co-reporter:Yunqing Jiang;Dr. Wenshuai Zhu; Huaming Li;Dr. Sheng Yin;Dr. Hua Liu ;Dr. Qingjie Xie
ChemSusChem 2011 Volume 4( Issue 3) pp:399-403
Publication Date(Web):
DOI:10.1002/cssc.201000251
Abstract
Oxidation of the sulfur-containing compounds benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) has been studied in a desulfurization system composed of model oil, hydrogen peroxide, and different types of ionic liquids [(C8H17)3CH3N]Cl/FeCl3, [(C8H17)3CH3N]Cl/CuCl2, [(C8H17)3CH3N]Cl/ZnCl2, [(C8H17)3CH3N]Cl/SnCl2, [(C4H9)3CH3N]Cl/FeCl3, [C10H21(CH3)3N]Cl/FeCl3, [(C10H21)2(CH3)2N]Cl/FeCl3. Deep desulfurization is achieved in the Fenton-like ionic liquid [(C8H17)3CH3N]Cl/FeCl3 at 25 °C for 1 h. The desulfurization of DBT reaches 97.9 %, in consuming very low amount of [(C8H17)3CH3N]Cl/FeCl3 (only 0.702 mmol). The reaction conditions, for example, the amount of [(C8H17)3CH3N]Cl/FeCl3 or H2O2, the temperature, and the molar ratio of FeCl3 to [(C8H17)3CH3N]Cl, are investigated for this system. The oxidation reactivity of the different sulfur-containing compounds is found to decrease in the order of DBT>BT>4,6-DMDBT. The desulfurization system can be recycled six times without significant decrease in activity. The sulfur level of FCC gasoline could be reduced from 360 ppm to 110 ppm.
Co-reporter:WenShuai Zhu, Huaming Li, QingQing Gu, Peiwen Wu, Guopeng Zhu, Yongsheng Yan, Guangying Chen
Journal of Molecular Catalysis A: Chemical 2011 Volume 336(1–2) pp:16-22
Publication Date(Web):14 February 2011
DOI:10.1016/j.molcata.2010.12.003
Three peroxo-molybdenum amino acid complexes (PMAACs) were synthesized and characterized. Their catalytic activities for oxidation of dibenzothiophene (DBT) in extraction and catalytic oxidative desulfurization system (ECODS) were evaluated using different ionic liquids. Comparing with simple catalyst Na2MoO4·2H2O in ECODS, PMAACs were effective wide-ranging catalysts and exhibited high desulfurization efficiency not only in water-miscible IL [bmim]BF4 but also in water-immiscible [bmim]PF6, [omim]BF4 and [omim]PF6. Especially 4,6-dimethyldibenzothiophene (4,6-DMDBT), the most difficult refractory compound in HDS, could be completely removed under optimal conditions. The reaction mechanism and desulfurization differences between using Na2MoO4·2H2O catalyst and PMAACs in water-miscible and water-immiscible ionic liquids have been investigated and explained by UV–vis. Kinetic parameters of the oxidation of DBT, BT and 4,6-DMDBT were studied.Graphical abstractResearch highlights▶ Peroxo-molybdenum amino acid complexes were effective wide-ranging catalysts in ECODS. ▶ High desulfurization was not only in water-miscible IL but also in water-immiscible IL. ▶ The most difficult refractory compound, 4,6-DMDBT in HDS, can be removed completely. ▶ Reaction mechanism in water-miscible and water-immiscible ILs was investigated. ▶ Desulfurization difference between using simple catalysts and PMAACs was explained.
Co-reporter:Jiexiang Xia, Sheng Yin, Huaming Li, Hui Xu, Li Xu, Qi Zhang
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2011 Volume 387(1–3) pp:23-28
Publication Date(Web):20 August 2011
DOI:10.1016/j.colsurfa.2011.07.023
BiOI uniform flower-like porous microspheres have been successfully synthesized through an EG-assisted solvothermal process in the presence of ionic liquid 1-butyl-3-methylimidazolium iodine ([bmim]I) and polyvinyl-pyrrolidone (PVP). The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), nitrogen sorption and diffuse reflectance spectroscopy (DRS). During the reactive process, ionic liquid not only acted as I source but also as template for the fabrication of BiOI porous microspheres. In addition, the photocatalytic activities experiments of BiOI catalyst on the degradation of methyl orange (MO) showed that as-prepared BiOI porous microspheres exhibited higher photocatalytic activity than that of BiOI nanoplates. On the basis of such analysis, it can be assumed that the enhanced photocatalytic activities of BiOI porous microspheres could be ascribed to its energy band structure, high Brunauer–Emmett–Teller (BET) surface area and high surface-to-volume ratios.Graphical abstractIn this paper, we developed a facile reactable ionic liquids (RILs) synthesis of BiOI porous microspheres by an EG-assisted solvothermal process. During the reactive process, it could be assumed that ionic liquid [bmim]I played an important role as solvent, reactant and template at the same time. Additionally, we evaluated the photocatalytic activities of BiOI on the degradation of MO under visible light irradiation and found that porous BiOI structures exhibited higher photocatalytic activity than BiOI nanoplates. The relationship between the structure of the photocatalyst and the photocatalytic activities was also discussed.Highlights► A novel method has been demonstrated to the synthesis of BiOI porous microspheres in the presence of a reactable ionic liquid 1-butyl-3-methylimidazolium iodine ([Bmim]I) and polyvinyl-pyrrolidone (PVP). ► During the reactive process, ionic liquid [Bmim]I played the role of solvent, reactant and template at the same time, and was vital for the flower-like BiOI porous architectures. ► The obtained porous BiOI catalyst showed the higher photocatalytic degradation activities of methyl orange (MO) than other BiOI catalysts in the literatures under the visible light irradiation.
Co-reporter:Jiexiang Xia, Sheng Yin, Huaming Li, Hui Xu, Yongsheng Yan, and Qi Zhang
Langmuir 2011 Volume 27(Issue 3) pp:1200-1206
Publication Date(Web):December 29, 2010
DOI:10.1021/la104054r
BiOI uniform flowerlike hollow microspheres with a hole in its surface structures have been successfully synthesized through an EG-assisted solvothermal process in the presence of ionic liquid 1-butyl-3-methylimidazolium iodine ([Bmim]I). The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), nitrogen sorption, and diffuse reflectance spectroscopy (DRS). A possible formation mechanism for the growth of hollow microspheres was discussed. During the reactive process, ionic liquid not only acted as solvents and templates but also as an I source for the fabrication of BiOI hollow microspheres and was vital for the structure of hollow microspheres. Additionally, we evaluated the photocatalytic activities of BiOI on the degradation of methyl orange (MO) under visible light irradiation and found that as-prepared BiOI hollow microspheres exhibited higher photocatalytic activity than BiOI nanoplates and TiO2 (Degussa, P25) did. On the basis of such analysis, it can be assumed that the enhanced photocatalytic activities of BiOI hollow microspheres could be ascribed to its energy band structure, high BET surface area, high surface-to-volume ratios, and light absorbance.
Co-reporter:Wangli Huang, Wenshuai Zhu, Huaming Li, Hua Shi, Guopeng Zhu, Hui Liu, and Guangying Chen
Industrial & Engineering Chemistry Research 2010 Volume 49(Issue 19) pp:8998-9003
Publication Date(Web):August 19, 2010
DOI:10.1021/ie100234d
A heteropolyanion-based ionic liquid, [(3-sulfonic acid) propylpyridine]3PW12O40·2H2O, [PSPy]3PW12O40·2H2O, abbreviated [PSPy]3PW, was synthesized and approved as an effective catalyst for desulfurization of fuels in [omim]PF6 by using aqueous H2O2 as oxidant. The catalysis was fulfilled with advantages of high activity, simplified workup, and flexible recyclability. The catalytic oxidation reactivity of sulfur-containing compounds was in the order dibenzothiophene (DBT) > 4,6-dimethyldibenzothiophene (4,6-DMDBT) > benzothiophene (BT). The effects of the amount of [PSPy]3PW, H2O2, and reaction time and temperature were investigated in detail. Under the optimal conditions, the removal of DBT achieved 99.4%. Especially, we found that the removal of 4,6-DMDBT could be up to 98.8%, and the system could be recycled at least 9 times without significant decrease in activity. The sulfur level of FCC gasoline could be reduced from 360 to 70 ppm in the extraction and catalytic oxidation system.
Co-reporter:Jiexiang Xia, Huaming Li, Zhijun Luo, Kun Wang, Sheng Yin, Yongsheng Yan
Applied Surface Science 2010 Volume 256(Issue 6) pp:1871-1877
Publication Date(Web):1 January 2010
DOI:10.1016/j.apsusc.2009.10.022
Abstract
Uniform peachstone-like CuO 3D architectures consisting of single-crystal nanosheets have been successfully synthesized by using ionic liquid 1-octyl-3-methylimidazolium trifluoroacetate ([Omim]TA) as capping reagents under the ionic liquid-assisted hydrothermal condition. Detailed proofs indicated that the process of crystal growth was dominated by an oriented aggregation and self-assemble growth mechanism. The morphology of CuO evolved from nanoparticles to two-dimensional (2D) nanosheets and three-dimensional (3D) peachstone-like nanostructures. A formation process is proposed to illustrate the growth of peachstone-like CuO crystal. The influence of the ionic liquid cations on the morphology of CuO materials was studied in detail. The cations of the ionic liquids control the morphology of crystals. Additionally, it was also found that the concentration of ionic liquids and the reaction time have direct influences on the morphology of the products. Their optical absorption spectra were also studied. The synthetic strategy could be extended to assemble 3D architectures of other materials.
Co-reporter:Jiexiang Xia, Huaming Li, Zhijun Luo, Hui Xu, Kun Wang, Sheng Yin, Yongsheng Yan
Materials Chemistry and Physics 2010 Volume 121(1–2) pp:6-9
Publication Date(Web):15 May 2010
DOI:10.1016/j.matchemphys.2010.01.046
Bi2WO6 uniform hierarchical nest-like structures have been successfully synthesized through an ionic liquid-assisted hydrothermal method in the presence of 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4). The Bi2WO6 hierarchical structures have an average diameter of about 3–5 μm and are assembled by Bi2WO6 nanosheets with size ranging from 16 to 20 nm. The results show that ionic liquid [Bmim]BF4 is vital for the formation of Bi2WO6 nest-like hierarchical structures. The UV–vis diffuse reflectance spectroscopy indicate that Bi2WO6 hierarchical nest-like structures induce a significantly enhanced optical absorbance in the UV–vis region, which is ascribed to multiple scattering within the hierarchical assemblies to the lengthened optical path length for light transporting.
Co-reporter:Huaming Li, Wenshuai Zhu, Yan Wang, Jingtong Zhang, Jidong Lu and Yongsheng Yan
Green Chemistry 2009 vol. 11(Issue 6) pp:810-815
Publication Date(Web):26 Mar 2009
DOI:10.1039/B901127G
Three redox ionic liquids based on iron chloride were synthesized and employed in extraction and catalytic oxidation desulfurization systems for removal of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) in model oil. Sulfur removal selectivity for S-compounds followed the order of DBT > 4,6-DMDBT > BT. Due to the redox properties of 1-butyl-3-methylimidazolium chloride iron chloride ([bmim]Cl/FeCl3) with addition of hydrogen peroxide, DBT removal can reach 99.2% under mild reaction conditions, which is not only higher than mere extraction with ionic liquid (IL), but also superior to two other ILs based on iron chloride under the same reaction conditions. Herein, [bmim]Cl/FeCl3 played a dual role in the process of desulfurization, not only acting as catalyst but also acting as an extractant. [bmim]Cl/FeCl3 is insoluble in n-octane, and the solubility in the model oil is also negligible. The used ionic liquid could be recycled for six times with a slight decrease in activity.
Co-reporter:Jingtong Zhang, Wenshuai Zhu, Huaming Li, Wei Jiang, Yunqing Jiang, Wangli Huang and Yongsheng Yan
Green Chemistry 2009 vol. 11(Issue 11) pp:1801-1807
Publication Date(Web):10 Sep 2009
DOI:10.1039/B914130H
The oxidation of dibenzothiophene (DBT), benzothiophene (BT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) in model oil was studied in the extraction and catalytic oxidative desulfurization (ECODS) system at room temperature (30 °C). Various Fenton-like reagents, such as Co2+, Cu2+, Ni2+, Mn2+, Cr3+, Fe3+ and H2O2, were screened for desulfurization in ionic liquids. The experimental results demonstrated that the desulfurization system containing anhydrous FeCl3, H2O2, and [bmim]BF4 exhibited high catalytic activity. The sulfur removal of DBT-containing model oil could reach 96.1%, which was obviously superior to mere solvent extraction with [bmim]BF4 (28.5%) or catalytic oxidation without [bmim]BF4 (7.3%). In a combination of extraction and oxidation, the sulfur content decreased from 500 ppm to 5 ppm, when the hydrogen peroxide was added into the desulfurization system in four batches. The catalytic oxidation reactivity of the sulfur-containing compounds was found to be in the following order: DBT > BT > 4,6-DMDBT. Moreover, the desulfurization system could be recycled five times without a significant decrease in activity.
Co-reporter:Hui Xu, Huaming Li, Li Xu, Chundu Wu, Guangsong Sun, Yuanguo Xu and Jinyu Chu
Industrial & Engineering Chemistry Research 2009 Volume 48(Issue 24) pp:10771
Publication Date(Web):October 9, 2009
DOI:10.1021/ie900835g
Rare-earth-loaded Ag3VO4 catalysts (RE3+-Ag3VO4, RE = Nd, Sm, and Eu) were prepared by the wetness impregnation technique and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS). The photocatalytic activities of the samples were evaluated by rhodamine B (RhB) dye degradation under visible-light irradiation. It was found that the presence of rare-earth oxides in the host Ag3VO4 could decrease the band gap and accelerate the separation of photogenerated electron−hole pairs, which led to higher photocatalytic activities. Among the rare-earth-loaded samples, Nd3+-loaded Ag3VO4 catalyst showed the highest photocatalytic activity. The optimum contents of Nd3+, Eu3+, and Sm3+ were found to be 2, 3, and 2 wt %, respectively. It was also found that the photocatalytic degradation of RhB over RE3+-Ag3VO4 (2 wt %) followed pseudo-first-order kinetics. A possible mechanism for RhB photocatalytic degradation over RE3+-Ag3VO4 catalysts is also proposed.
Co-reporter:Huaming Li, Xue Jiang, Wenshuai Zhu, Jidong Lu, Huoming Shu and Yongsheng Yan
Industrial & Engineering Chemistry Research 2009 Volume 48(Issue 19) pp:9034-9039
Publication Date(Web):September 2, 2009
DOI:10.1021/ie900754f
Three decatungstates with short carbon chains as the cations, such as tetrabutylammonium decatungstate ([(C4H9)4N]4W10O32), tetramethylammonium decatungstate ([(CH3)4N]4W10O32), and benzyltriethylammonium decatungstate ([(C2H5)3NC7H7]4W10O32), were synthesized and then used as a catalyst in the extractive catalytic oxidative desulfurization (ECODS) system in the ionic liquid (IL) of [Bmim]PF6, and hydrogen dioxide (H2O2) was used as an oxidant. During the optimized process, the sulfur level in the model oil (1000 ppm S) can be reduced to 8 ppm, which is consistent with the standards of deep desulfurization. The temperature, the reaction time, and the amount of H2O2 and catalyst, as well as the type of the cations of decatungstates, all played vital roles in desulfurization efficiency, which were studied in detail to optimize the reaction conditions. The system could be recycled five times before the sulfur removal decreased sharply.
Co-reporter:Dan Xu, Wenshuai Zhu, Huaming Li, Jingtong Zhang, Fang Zou, Hua Shi and Yongsheng Yan
Energy & Fuels 2009 Volume 23(Issue 12) pp:5929-5933
Publication Date(Web):October 6, 2009
DOI:10.1021/ef900686q
An extraction and catalytic oxidation desulfurization (ECODS) system composed of V2O5, 30 wt % H2O2 and 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) as the basic experiment was used for the removal of DBT from the model oil at moderate temperature (30 °C). In the reaction process, V2O5 was oxidized by H2O2 into peroxovanadium compounds. Meanwhile, the sulfur-containing compounds, such as benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT), were extracted into ionic liquid (IL) from the model oil and oxidized into their corresponding sulfones by peroxovanadium compounds. The reactivity of sulfur-containing compounds in the ECODS followed this order: DBT > BT > 4,6-DMDBT. In the case of ECODS, the sulfur removal of DBT can reach 98.7%, which was superior to that of the simple extraction with IL (16.5%) or the catalytic oxidation (2.8%). This ECODS system could be recycled seven times without a significant decrease in activity.
Co-reporter:Huaming Li, Lining He, Jidong Lu, Wenshuai Zhu, Xue Jiang, Yan Wang and Yongsheng Yan
Energy & Fuels 2009 Volume 23(Issue 3) pp:1354-1357
Publication Date(Web):February 12, 2009
DOI:10.1021/ef800797n
A simplified extraction and catalytic oxidative desulfurization (ECODS) system composed of phosphotungstic acid (H3PW12O40·14H2O), 30% H2O2, and [bmim]BF4 was found suitable for the deep removal of sulfur in model oil. By this desulfurization system dibenzothiophene (DBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), and benzothiophene (BT) could be effectively removed. Removal of DBT could reach 98.2% at room temperature (30 °C) for 1 h, which was remarkably superior to mere solvent extraction with IL (14.2%) or catalytic oxidation without IL (15.9%). When the reaction temperature increased to 70 °C, treatment of BT, DBT, and 4,6-DMDBT with our ECODS system showed 100% removal of sulfur compounds in 3 h. This desulfurization system could be recycled five times with slight decrease in activity.
Co-reporter:Jiexiang Xia, Huaming Li, Zhijun Luo, Hua Shi, Kun Wang, Huoming Shu, Yongsheng Yan
Journal of Physics and Chemistry of Solids 2009 Volume 70(Issue 11) pp:1461-1464
Publication Date(Web):November 2009
DOI:10.1016/j.jpcs.2009.08.006
Flower-like and leaf-like cupric oxide (CuO) single-crystal nanostructures have been successfully synthesized using ionic liquid 1-octyl-3-methylimidazolium trifluoroacetate ([Omim]TA) under the microwave-assisted approach. By controlling the concentration of [Omim]TA and reaction temperature, shape transformation of CuO nanostructures could be achieved in a short period of time. The results indicate that ionic liquid [Omim]TA plays an important role in the formation of different morphologies of CuO crystals. The crystal structure and morphology of products were characterized by X-ray powder diffraction (XRD), infrared spectrum (IR), scanning electron microscope (SEM), transmission electron microscopy (TEM), and selected-area electron diffraction (SAED). A possible mechanism for CuO nanostructure was proposed. In addition, UV–vis spectroscopy was employed to estimate the band gap energies of CuO crystals.
Co-reporter:Huaming Li;Wenshuai Zhu;Jidong Lu;Xue Jiang
Reaction Kinetics, Mechanisms and Catalysis 2009 Volume 96( Issue 1) pp:165-173
Publication Date(Web):2009 February
DOI:10.1007/s11144-009-5426-7
The catalytic system of pristine simple tungstic acid and quaternary ammonium salts has been found suitable for deep removal of sulfur in diesel with H2O2 as oxidant. The longer the length of the carbon chain of the quaternary ammonium salt is, the better its catalytic activity is in desulfurization. By combining oxidation and extraction with dimethylformamide, low sulfur level in diesel could be obtained.
Co-reporter:Lining He, Huaming Li, Wenshuai Zhu, Junxiang Guo, Xue Jiang, Jidong Lu and Yongsheng Yan
Industrial & Engineering Chemistry Research 2008 Volume 47(Issue 18) pp:6890-6895
Publication Date(Web):August 6, 2008
DOI:10.1021/ie800857a
A combination of catalytic oxidation and extraction in ionic liquid (IL) was used for the removal of benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) from the model oil. Three peroxophosphomolybdates Q3{PO4[MoO(O2)2]4} (Q = [(C4H9)4N]+, [C14H29N(CH3)3]+ and [C16H33NC5H5]+) were synthesized and characterized. In the catalytic oxidation desulfurization (CODS) system containing the peroxophosphomolybdate with short alkyl chain ([(C4H9)4N]3{PO4[MoO(O2)2]4}) and H2O2, the process exhibited low sulfur removal (16.8%). However, with addition of 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4), the extraction and catalytic oxidative desulfurization (ECODS) system remarkably increased the removal of sulfur to 97.3% (with stoichiometric amounts of H2O2). The process was superior to the simple extraction with IL (16.3%). The results demonstrated that the ECODS system could deeply remove DBT from the model oil, and this desulfurization system could be recycled 4 times with slight decrease in activity. We also found that the catalysts with short alkyl chains exhibited higher catalytic activity than that with long alkyl chain in the ECODS system. Moreover, the reactivity of sulfur compounds decreased in the order of DBT > 4,6-DMDBT > BT.
Co-reporter:Zhijun Luo, Huaming Li, Huoming Shu, Kun Wang, Jiexiang Xia, Yongsheng Yan
Materials Chemistry and Physics 2008 Volume 110(Issue 1) pp:17-20
Publication Date(Web):15 July 2008
DOI:10.1016/j.matchemphys.2008.01.012
A new type of BaMoO4 spherical nanostructure consisting of numbers of nanosheets has been successfully synthesized through a very simple reflux method under microwave irradiation. Our result shows that the concentration of initial reagents and the reaction temperature played important roles in the formation of BaMoO4 crystal with different morphology. The products were characterized by X-ray powder diffraction (XRD), Scanning electron microscope (SEM), transmission electron microscopy (TEM) and electron diffraction (ED).
Co-reporter:Hui Xu, Huaming Li, Chundu Wu, Jinyu Chu, Yongsheng Yan, Huoming Shu
Materials Science and Engineering: B 2008 Volume 147(Issue 1) pp:52-56
Publication Date(Web):25 January 2008
DOI:10.1016/j.mseb.2007.11.011
The Fe-, Co- and Cu-loaded BiVO4 were synthesized by wet impregnation method. The physical and photophysical properties of the samples were characterized by ICP-OES, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis diffused reflectance spectroscopy (DRS), photoluminescence (PL) and specific surface area. The XRD analysis confirmed that all photocatalysts had the same crystal forms with the single monoclinic scheelite structure. The results showed that Fe2O3, Co3O4 and CuO existed on the surface of M-BiVO4 catalysts (M = Fe, Co and Cu), respectively. The red-shifted trend of absorption band by DRS studies was as follows: Co-BiVO4 > Cu-BiVO4 > Fe-BiVO4 > pure BiVO4. The observed trends for the PL intensities of M-BiVO4 were Co-BiVO4 > Fe-BiVO4 > Cu-BiVO4. The influence of different transition metal oxides loading (Fe2O3, Co3O4 and CuO) on the photocatalytic activity for photocatalytic decolorization of methylene blue (MB) was discussed under UV and visible light irradiation. It is found that Cu-loaded BiVO4 showed the highest reaction activity among all transition metal oxides-loaded samples.
Co-reporter:Zhijun Luo, Huaming Li, Jiexiang Xia, Wenshuai Zhu, Junxiang Guo, Beibei Zhang
Materials Letters 2007 Volume 61(8–9) pp:1845-1848
Publication Date(Web):April 2007
DOI:10.1016/j.matlet.2006.07.143
Single-crystal BaWO4 nanosheets and nanobelts have been successfully synthesized by using polymer PVP micelle as templates in a reflux system under microwave irradiation. Our result shows that the concentration of PVP aqueous solutions played an important role in the formation of BaWO4 crystal with different morphologies. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and electron diffraction (ED).
Co-reporter:Jinyuan Liu, Yanhua Song, Hui Xu, Xingwang Zhu, Jiabiao Lian, Yuanguo Xu, Yan Zhao, Liying Huang, Haiyan Ji, Huaming Li
Journal of Colloid and Interface Science (15 May 2017) Volume 494() pp:
Publication Date(Web):15 May 2017
DOI:10.1016/j.jcis.2017.01.010
Nitrogen-doped carbon nanotubes (N-CNT) is a promising metal-free candidate and electronic acceptor. It has been employed to modify mesoporous carbon nitride (mpg-C3N4) for photocatalytic degradation of organic dye and antibiotics under visible-light irradiation. Herein, we report a facile synthesis strategy involving polymerization of cyanamide as the precursor in the presence of N-CNT via thermal polycondensation. The morphology and structure of as-prepared N-CNT/mpg-C3N4 were analyzed by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The N-CNT/mpg-C3N4-15 exhibited increased photocatalytic activity for rhodamine B (RhB), methyl orange (MO) and tetracycline hydrochloride (TC) degradation compared with the pure one under visible-light irradiation, which is mainly due to the efficiently separation of photogenerated electron-hole pairs for the introduction of N-CNT as electronic acceptor. The photocatalytic reaction can fit the first order kinetics. Additionally, superoxide radical (O2−) was regarded as main reactive species participating in the photodegradation reaction process. Furthermore, the reason for enhancing photocatalytic activity of N-CNT/mpg-C3N4 is mainly attributed to synergistic effects between mpg-C3N4 as main ingredient and N-CNT as electron acceptor.We report a facile synthesis strategy involving polymerization of cyanamide as the precursor in the presence of N-CNT via thermal polycondensation. The N-CNT/mpg-C3N4 exhibited enhanced photocatalytic activity for Rhodamine B (RhB), Methyl orange (MO) and Tetracycline (TC) degradation compared with the pure one under visible-light irradiation, which is mainly due to the efficiently separation of photogenerated electron-hole pairs for the introduction of N-CNT as electronic transfer channels. The photocatalytic reaction can fit as first order kinetics. Additionally, superoxide radical (O2•−) was regarded as main reactive species participate in the photodegradation reaction process. Furthermore, the proposed mechanism for enhancing photocatalytic activity of N-CNT/mpg-C3N4 is attributed to synergistic effects between mpg-C3N4 as main ingredient and N-CNT as transfer media.Figure optionsDownload full-size imageDownload high-quality image (217 K)Download as PowerPoint slide
Co-reporter:Hui Xu, Huaming Li, Guangsong Sun, Jiexiang Xia, Chundu Wu, Zhixiang Ye, Qi Zhang
Chemical Engineering Journal (15 May 2010) Volume 160(Issue 1) pp:33-41
Publication Date(Web):15 May 2010
DOI:10.1016/j.cej.2010.02.054
La2O3/Ag3VO4 samples were synthesized by impregnation process and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS). The XRD, SEM–EDS and XPS analyses revealed that La3+ was dispersed on Ag3VO4 in the form of La2O3 cluster. The DRS results indicated that the absorption edge of the La3+–Ag3VO4 catalyst shifted to longer wavelength. The enhanced photocatalytic activity of La2O3/Ag3VO4 for Rhodamine B (RhB) dye degradation under visible light irradiation was due to its wider absorption edge and higher separation rate of photo-generated electron and holes. The highest photodegradation efficiency was obtained when the La2O3/Ag3VO4 catalyst was calcined at 300 °C with 3 wt% La content. The photocatalytic degradation intermediates of the solution were identified by LC/MS.
Co-reporter:Xiaojie She, Liang Liu, Haiyan Ji, Zhao Mo, Yeping Li, Liying Huang, Daolin Du, Hui Xu, Huaming Li
Applied Catalysis B: Environmental (15 June 2016) Volume 187() pp:144-153
Publication Date(Web):15 June 2016
DOI:10.1016/j.apcatb.2015.12.046
Co-reporter:Hua Shi, Wenshuai Zhu, Huaming Li, Hua Liu, Ming Zhang, Yongsheng Yan, Zhigao Wang
Catalysis Communications (10 March 2010) Volume 11(Issue 7) pp:588-591
Publication Date(Web):10 March 2010
DOI:10.1016/j.catcom.2009.12.025
A variety of Brönsted acidic ionic liquids were screened as catalysts for the esterification of salicylic acid. The experimental results indicated that SO3H-functionalized ionic liquids with HSO4- performed high catalytic activity under microwave irradiation, and the yields can reach 91.9–93.6%. Furthermore, ionic liquids can be easily separated by simple decantation and have a fair reusability. The Brönsted acidity–catalytic activity relationships were also investigated and the results showed that the activity of the acidic ionic liquids is in excellent agreement with their acidity order.
Co-reporter:Xiaojie She, Hui Xu, Yuanguo Xu, Jia Yan, Jiexiang Xia, Li Xu, Yanhua Song, Yan Jiang, Qi Zhang and Huaming Li
Journal of Materials Chemistry A 2014 - vol. 2(Issue 8) pp:NaN2570-2570
Publication Date(Web):2013/11/12
DOI:10.1039/C3TA13768F
Due to their unprecedented electronic, surface and optical properties, the atomic-thick graphene-like materials have aroused great interest. Compared with the bulk counterparts, the graphene-like material can not only enhance the internal properties, but also gives rise to new promising properties. Herein, the graphene-like carbon nitride (graphene-like C3N4) was synthesized via liquid exfoliation from the bulk graphitic carbon nitride (g-C3N4) in 1,3-butanediol (1,3-BUT) for the first time. And the graphene-like C3N4 was characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), thermogravimetric analysis (TG), and X-ray photoelectron spectroscopy (XPS). The obtained graphene-like C3N4 exhibited a two-dimensional thin-layer structure with about 3–6 atoms thickness, a high specific surface area of 32.54 m2 g−1, increased photocurrent responses, improved electron transport ability and enhanced photocatalytic activity. The photocatalytic reaction for the organic dye methylene blue (MB) by the graphene-like C3N4 followed first-order kinetics. Moreover, the graphene-like C3N4 exhibited a higher apparent rate of 0.1262 min−1, which was 3.1 times higher than that of the bulk g-C3N4 (0.0409 min−1). The enhanced photocatalytic reaction was due to a high specific surface area and a larger bandgap (by 0.14 eV). The yield of the graphene-like C3N4 was up to ∼0.35 mg mL−1. Moreover, the graphene-like C3N4 had a new property that it could be used as the sensor for trace amounts of Cu2+ determination, so the graphene-like C3N4 is a new but promising candidate for heavy metal ions (Cu2+) determination in water environment. Photoelectrochemical selective sensing of trace amounts of Cu2+ was also discussed.
Co-reporter:Peiwen Wu, Wenshuai Zhu, Yanhong Chao, Jinshui Zhang, Pengfei Zhang, Huiyuan Zhu, Changfeng Li, Zhigang Chen, Huaming Li and Sheng Dai
Chemical Communications 2016 - vol. 52(Issue 1) pp:NaN147-147
Publication Date(Web):2015/10/16
DOI:10.1039/C5CC07830J
Hexagonal boron nitride nanosheets (h-BNNs) with rather high specific surface area (SSA) are important two-dimensional layer-structured materials. Here, a solvent-mediated synthesis of h-BNNs revealed a template-free lattice plane control strategy that induced high SSA nanoporous structured h-BNNs with outstanding aerobic oxidative desulfurization performance.
Co-reporter:Jiexiang Xia, Sheng Yin, Huaming Li, Hui Xu, Li Xu and Yuanguo Xu
Dalton Transactions 2011 - vol. 40(Issue 19) pp:NaN5258-5258
Publication Date(Web):2011/04/06
DOI:10.1039/C0DT01511C
BiOBr uniform flower-like hollow microsphere and porous nanosphere structures have been successfully synthesized through a one-pot EG-assisted solvothermal process in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br). The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). Possible formation mechanism for the growth of hollow microspheres was discussed. During the reactive process, ionic liquid [C16mim]Br played the role of solvent, reactant and template at the same time. Moreover, the photocatalytic activities of BiOBr flower-like hollow and porous structures were evaluated on the degradation of rhodamine B (RhB) under visible light irradiation. The results assumed that BiOBr porous nanospheres sample showed much higher photocatalytic activity than the conventionally prepared sample and TiO2 (Degussa, P25). The relationship between the structure of the photocatalyst and the photocatalytic activities were also discussed in detail; it can be assumed that the enhanced photocatalytic activities of BiOBr materials could be ascribed to a synergistic effect, including high BET surface area, the energy band structure, the smaller particle size and light absorbance.
Co-reporter:Yanhua Song, Yucheng Lei, Hui Xu, Cheng Wang, Jia Yan, Haozhu Zhao, Yuanguo Xu, Jiexiang Xia, Sheng Yin and Huaming Li
Dalton Transactions 2015 - vol. 44(Issue 7) pp:NaN3066-3066
Publication Date(Web):2014/12/05
DOI:10.1039/C4DT03242J
Novel few-layer MoS2/Ag3PO4 composites were fabricated. The results indicated that Ag3PO4 nanoparticles were directly formed on the surface of few-layer MoS2. The physical and chemical properties of the few-layer MoS2/Ag3PO4 composite photocatalysts were tested in order to investigate the effects of few-layer MoS2 on the photocatalytic activity of Ag3PO4. The photocatalytic activity of the few-layer MoS2/Ag3PO4 composites was evaluated by the photocatalytic degradation of Rhodamine B (RhB) and bisphenol A (BPA) under visible light irradiation. The photocatalytic activity of the few-layer MoS2/Ag3PO4 composites was higher than that of pure Ag3PO4. The optimal few-layer MoS2 content for the organic pollutant degradation of the heterojunction structures was determined. The synergic effect between few-layer MoS2 and Ag3PO4 was found to lead to an improved photogenerated carrier separation. The stability and the possible photocatalytic mechanism of the composites were also discussed.
Co-reporter:Yuanguo Xu, Hui Xu, Jia Yan, Huaming Li, Liying Huang, Qi Zhang, Chuanjing Huang and Huilin Wan
Physical Chemistry Chemical Physics 2013 - vol. 15(Issue 16) pp:NaN5830-5830
Publication Date(Web):2013/02/11
DOI:10.1039/C3CP44104K
A facile, one-step synthesis of carbon nanotube (CNT)-loaded Ag/AgBr is reported. The as-prepared samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), UV/Vis absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, photoluminescence (PL) spectroscopy and electrochemical impedance spectroscopy (EIS). The CNT/Ag/AgBr composite exhibited much higher photocatalytic activity than pure Ag/AgBr in degrading methyl orange (MO) dye solution. The loading amount of CNT had a significant influence on the photoactivity of the CNT/Ag/AgBr composite. When the CNT loading amount was 1.4 at%, the hybrid material showed the highest photocatalytic ability. The result showed that a small amount of CNT was beneficial for photo-generated electron transfer, which could enhance the photoactivity of CNT/Ag/AgBr. The degradation dye solution was tested by liquid chromatography/mass spectrometry (LC/MS) and total organic carbon (TOC) analysis. Based on the results, the structure of the synthesized CNT/Ag/AgBr hybrid material was verified and the possible degradation path of the MO dye was proposed. A possible visible-light photocatalytic degradation mechanism was also discussed.
Co-reporter:Xiaojie She, Hui Xu, Hefei Wang, Jiexiang Xia, Yanhua Song, Jia Yan, Yuanguo Xu, Qi Zhang, Daolin Du and Huaming Li
Dalton Transactions 2015 - vol. 44(Issue 15) pp:NaN7031-7031
Publication Date(Web):2015/01/26
DOI:10.1039/C4DT03793F
This research has developed a photocatalytic reactor that includes circulating water, light, and a temperature control system. CeO2/g-C3N4 composites with high photocatalytic activity and stability were synthesized by a simple and facile hydrothermal method. The obtained photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It was found that in the CeO2/g-C3N4 composites, the CeO2 nanoparticles were homogeneously cubic in shape (from 3 to 10 nm) and were evenly dispersed on the surface of the g-C3N4. At constant temperature (30 °C), 5% CeO2/g-C3N4 photocatalyst showed the best photocatalytic activity for degrading organic dye methylene blue (MB) under visible light irradiation. The photocatalytic reaction for degrading MB followed first-order kinetics and 5% CeO2/g-C3N4 exhibited a higher apparent rate of 1.2686 min−1, 7.8 times higher than that of the pure g-C3N4 (0.1621 min−1). In addition, it was found that 5% CeO2/g-C3N4 had a new property that it could be used as a sensor for the determination of trace amounts of Cu2+. Such unique design and one-step synthesis, with an exposed high-activity surface, are important for both technical applications and theoretical investigations.
Co-reporter:Yuanguo Xu, Hui Xu, Lei Wang, Jia Yan, Huaming Li, Yanhua Song, Liying Huang and Guobin Cai
Dalton Transactions 2013 - vol. 42(Issue 21) pp:NaN7613-7613
Publication Date(Web):2013/02/28
DOI:10.1039/C3DT32871F
A novel, multi-walled carbon nanotubes (CNT) modified white C3N4 composite (CNT/white C3N4) with enhanced visible-light-response photoactivity was prepared. The white C3N4 and CNT combined together and formed the CNT/white C3N4 composite due to electrostatically-driven self-assembly with the hydrothermal method. The as-prepared white C3N4 and CNT/white C3N4 composite photocatalyst were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-vis absorption spectra, X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). The photoelectrochemical i–t curves were tested using several on–off cycles of light irradiation. The photoactivity of the catalysts was evaluated by degrading methylene blue (MB) dye solution. The results showed that the photoactivity for the degradation of MB solution was in the following order: CNT/white C3N4 composite > C3N4 > the white C3N4. The photoactivity of the CNT/white C3N4 composite was 66.5% and 34.5% higher than that of the white C3N4 sample and that of the C3N4 at 1.5 h, respectively. The degradation rate of the CNT/white C3N4 photocatalyst was almost 8.1 times as high as that of the white C3N4. The results indicated that CNT played an important role, which led to the efficient separation of the photo-generated charge carriers. The reason why the photoactivity of the CNT/white C3N4 was much higher than that of C3N4 and the white C3N4 was discussed. A possible mechanism of CNT on the enhancement of composites' visible light performance was also proposed.
Co-reporter:Hui Xu, Yuanguo Xu, Huaming Li, Jiexiang Xia, Jun Xiong, Sheng Yin, Chuanjing Huang and Huilin Wan
Dalton Transactions 2012 - vol. 41(Issue 12) pp:NaN3394-3394
Publication Date(Web):2012/02/06
DOI:10.1039/C2DT11969B
A novel heterojunction AgBr/BiPO4 photocatalyst was synthesized with the hydrothermal method. The photocatalyst was characterized by X-Ray powder Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectrometry (EDS), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectrscopy (XPS) and Diffuse Reflectance Spectroscopy (DRS). The XRD, SEM-EDS, TEM and XPS analyses indicated that the heterojunction structure formed during the process of hydrothermal treatment. The photocatalytic activity of the photocatalysts was evaluated by degradation of methylene blue dye (MB). The results indicated that the AgBr/BiPO4 heterojunction exhibited a much higher photocatalytic activity than the pure BiPO4. The mechanism of the enhancing AgBr/BiPO4 heterojunction's photocatalytic activity was discussed. It was also found that the photocatalytic degradation of MB over AgBr/BiPO4 heterojunction photocatalysts followed the pseudo-first-order reaction model.
Co-reporter:Jun Xiong, Wenshuai Zhu, Hongping Li, Lei Yang, Yanhong Chao, Peiwen Wu, Suhang Xun, Wei Jiang, Ming Zhang and Huaming Li
Journal of Materials Chemistry A 2015 - vol. 3(Issue 24) pp:NaN12747-12747
Publication Date(Web):2015/05/01
DOI:10.1039/C5TA01346A
Novel carbon-doped porous boron nitride (C-BN) has been successfully prepared by using 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) as a soft template and the carbon source via calcination under N2 atmosphere. Multiple techniques were applied to investigate the structure, morphology, and adsorptive desulfurization performance. The metal-free porous C-BN displayed enhanced adsorption performance for dibenzothiophene (DBT) than pure BN materials and exhibited one of the highest adsorption capacities reported up to now (49.75 mg S g−1 adsorbent according to the Langmuir isotherm model, 35.2 mg S g−1 adsorbent for 500 ppm sulfur model oil). After three times recycling, the adsorption capacity slightly decreased from 35.2 to 27.2 mg S g−1 adsorbent. The excellent adsorption performance of porous C-BN was attributed to the more exposed atoms along the edges of the pores and the stronger Lewis acid–base interactions between DBT and carbon-doped porous BN. Moreover, it is believed that this strategy to control the structure and composition of BN can be extended to incorporate other heteroatoms and control the pore size for BN materials by changing the anion or cation of the ionic liquids.
Co-reporter:Hongping Li, Yonghui Chang, Wenshuai Zhu, Changwei Wang, Chao Wang, Sheng Yin, Ming Zhang and Huaming Li
Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 43) pp:NaN28742-28742
Publication Date(Web):2015/09/22
DOI:10.1039/C5CP04172D
The nature of the interaction between deep eutectic solvents (DESs), formed by ChCl and glycerol, and SO2 has been systematically investigated using the M06-2X density functional combined with cluster models. Block-localized wave function energy decomposition (BLW-ED) analysis shows that the interaction between SO2 and DESs is dominated by a charge transfer interaction. After this interaction, the SO2 molecule becomes negatively charged, whereas the ChCl–glycerol molecule is positively charged, which is the result of Lewis acid–base interaction. The current result affords a theoretical proof that it is highly useful and efficient to manipulate the Lewis acidity of absorbents for SO2 capture. Moreover, hydrogen bonding as well as electrostatic interactions may also contribute to the stability of the complex. Structure analysis shows that solvent molecules will adjust their geometries to interact with SO2. In addition, the structure of SO2 is barely changed after interaction. The interaction energy between different cluster models and SO2 ranges from −6.8 to −14.4 kcal mol−1. It is found that the interaction energy is very sensitive to the solvent structure. The moderate interaction between ChCl–glycerol and SO2 is consistent with the concept that highly efficient solvents for SO2 absorption should not only be solvable but also regenerable.
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![2,5-Cyclohexadien-1-one, 4-[(4-hydroxyphenyl)methylene]-](http://img.cochemist.com/ccimg/19100/19052-70-1_b.png)
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