Co-reporter:Jian Li;Runni Wu;Zhijiao Jing;Long Yan;Fei Zha
Langmuir October 6, 2015 Volume 31(Issue 39) pp:10702-10707
Publication Date(Web):2017-2-22
DOI:10.1021/acs.langmuir.5b02734
A simple method was used to generate colorful hydrophobic stearate particles via chemical reactions between inorganic salts and sodium stearate. Colored self-cleaning superhydrophobic coatings were prepared through a facile one-step spray-coating process by spraying the stearate particle suspensions onto stainless steel substrates. Furthermore, the colorful superhydrophobic coating maintains excellent chemical stability under both harsh acidic and alkaline circumstances. After being immersed in a 3.5 wt % NaCl aqueous solution for 1 month, the as-prepared coatings remained superhydrophobic; however, they lost their self-cleaning property with a sliding angle of about 46 ± 3°. The corrosion behavior of the superhydrophobic coatings on the Al substrate was characterized by the polarization curve and electrochemical impedance spectroscopy (EIS). The electrochemical corrosion test results indicated that the superhydrophobic coatings possessed excellent corrosion resistance, which could supply efficient and long-term preservation for the bare Al substrate.
Co-reporter:Xiaozhong Zhou, Zhengfeng Zhang, Xiaofang Lu, Xueyan Lv, Guofu Ma, Qingtao Wang, and Ziqiang Lei
ACS Applied Materials & Interfaces October 11, 2017 Volume 9(Issue 40) pp:34927-34927
Publication Date(Web):September 21, 2017
DOI:10.1021/acsami.7b10107
Sb2O3 nanoparticles are uniformly anchored on reduced graphene oxide (rGO) sheets via a facile and ecofriendly route based on the alcohol dissolution–reprecipitation method. Such obtained Sb2O3/rGO composite demonstrates a highly reversible specific capacity (1355 mA h g–1 at 100 mA g–1), good rate capability, and superior life cycle (525 mA h g–1 after 700 cycles at 600 mA g–1) when used an anode electrode for lithium-ion batteries (LIBs). The outstanding electrochemical properties of Sb2O3/rGO composite could be attributed to its unique structure in which the strong electronic coupling effect between Sb2O3 and rGO leads to an enhanced electronic conductivity, structure stability, and electrochemical activity during reversible conversion-alloying reactions. Also, these findings are helpful in both developing novel high-performance electrodes for LIBs and synthesizing functional materials in an ecofriendly and economical way.Keywords: alcohol dissolution−reprecipitation method; electronic coupling effect; lithium-ion batteries; lithium-storage properties; Sb2O3/rGO composite;
Co-reporter:Xiaozhong Zhou, Zhengfeng Zhang, Xiaofang Lu, Xueyan Lv, Guofu Ma, Qingtao Wang, and Ziqiang Lei
ACS Applied Materials & Interfaces October 11, 2017 Volume 9(Issue 40) pp:34927-34927
Publication Date(Web):September 21, 2017
DOI:10.1021/acsami.7b10107
Sb2O3 nanoparticles are uniformly anchored on reduced graphene oxide (rGO) sheets via a facile and ecofriendly route based on the alcohol dissolution–reprecipitation method. Such obtained Sb2O3/rGO composite demonstrates a highly reversible specific capacity (1355 mA h g–1 at 100 mA g–1), good rate capability, and superior life cycle (525 mA h g–1 after 700 cycles at 600 mA g–1) when used an anode electrode for lithium-ion batteries (LIBs). The outstanding electrochemical properties of Sb2O3/rGO composite could be attributed to its unique structure in which the strong electronic coupling effect between Sb2O3 and rGO leads to an enhanced electronic conductivity, structure stability, and electrochemical activity during reversible conversion-alloying reactions. Also, these findings are helpful in both developing novel high-performance electrodes for LIBs and synthesizing functional materials in an ecofriendly and economical way.Keywords: alcohol dissolution−reprecipitation method; electronic coupling effect; lithium-ion batteries; lithium-storage properties; Sb2O3/rGO composite;
Co-reporter:Hui Peng, Chunding Wei, Kai Wang, Tianyu Meng, Guofu Ma, Ziqiang Lei, and Xiong Gong
ACS Applied Materials & Interfaces May 24, 2017 Volume 9(Issue 20) pp:17067-17067
Publication Date(Web):May 9, 2017
DOI:10.1021/acsami.7b02776
In this study, we report novel Ni0.85Se@MoSe2 nanosheet arrays prepared by a facile one-step hydrothermal method through nickel (Ni) foam as Ni precursor and the framework of MoSe2. Owing to the unique interconnection and hierarchical porous nanosheet array architecture, the Ni0.85Se@MoSe2 nanosheet arrays exhibit a high specific capacitance of 774 F g–1 at the current density of 1 A g–1, which is almost 2 times higher than that (401 F g–1) of the Ni0.85Se matrix and about 7 times greater than that (113 F g–1) of the MoSe2 nanoparticles. Moreover, we report an asymmetric supercapacitor (ASC), which is fabricated by using the Ni0.85Se@MoSe2 nanosheet arrays as the positive electrode and the graphene nanosheets (GNS) as the negative electrode, with aqueous KOH as the electrolyte. The Ni0.85Se@MoSe2//GNS ASC possesses an output voltage of 1.6 V, an energy density of 25.5 Wh kg–1 at a power density of 420 W kg–1, and a cycling stability of 88% capacitance retention after 5000 cycles. These results indicate that the Ni0.85Se@MoSe2 nanosheet arrays are a good electrode for supercapacitors.Keywords: heterostructure; molybdenum selenide; nanosheet arrays; nickel selenide; supercapacitor;
Co-reporter:Hengchang Ma;Manyi Yang;Caili Zhang;Yucheng Ma;Yanfang Qin;Lu Chang;Lei Lei;Tao Wang;Yuan Yang
Journal of Materials Chemistry B 2017 vol. 5(Issue 43) pp:8525-8531
Publication Date(Web):2017/11/08
DOI:10.1039/C7TB02399E
Aggregation-induced emission (AIE)-active compounds are attractive fluorescent materials for applications in chemical and biological sensing. The AIE effect of such materials amplifies changes in the fluorescence signal due to the physical state transformation from aggregation to disaggregation, which can be employed for detecting various analytes with high sensitivity. In particular, specific bio-active analyte recognition is not only very interesting but also challenging. In this paper, we report a set of novel AIE-active fluorescent probes containing pyridiniums and boric acid groups (TPA-PP, TPA-PPA-1, TPA-PPA-2, TPA-PPA-3), which has been developed for adenosine 5′-triphosphate (ATP) recognition. These probes with two types of interaction modes and multiple connection sites toward ATP molecules are able to selectively discriminate ATP among other bioactive anions with a significant enhancement in fluorescence emission. In particular, in the application of cell imaging, as the number of positive charges and boric acid group increased further, the probes could penetrate into cells, and then enter into the nucleus very specifically. These results clearly demonstrate that the newly developed sensors are suitable for specific tracing of different cell organelles with a height visualization and retention ability. Therefore, all of them are confirmed as promising alternatives for live cell imaging in the future.
Co-reporter:Enke Feng;Guofu Ma;Kanjun Sun;Feitian Ran;Hui Peng
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 5) pp:1986-1992
Publication Date(Web):2017/02/28
DOI:10.1039/C6NJ02710E
A primary challenge of gel electrolytes in the development of flexible and wearable devices is their weak mechanical strength and poor electrochemical performances. Here, we prepare a novel PVA (polyvinyl alcohol)–H2SO4–BAAS (bromamine acid sodium) gel polymer with a porous network structure as both electrolyte and separator, which achieves excellent mechanical strength, maintains a high ionic conductivity of 21.4 mS cm−1 and provides a reversible redox reaction for enhanced supercapacitor performance. Surprisingly, the operating voltage of the present active electrolyte enhanced supercapacitor (AEESC) is up to 1.5 V, which is much larger than that of the previously reported active electrolyte based supercapacitors (about 1.0 V). Furthermore, the AEESC exhibits a maximum specific capacitance of 390 F g−1 at a current density of 0.8 A g−1, a remarkably high energy density of 30.5 W h kg−1 at a power density of 600 W kg−1 and good cycling stability. Additionally, such a device displays only a small capacitance loss when the gel polymer is under a large tensile strain of 100% or under a high pressure of 2000 kPa. Meanwhile, the capacitance of the device was maintained very well after 500 complete bending cycles, indicating that the robust gel polymer endows the fabricated AEESC with good flexibility and electrochemical stability.
Co-reporter:Enke Feng;Hui Peng;Zhiguo Zhang;Jindan Li
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 17) pp:9024-9032
Publication Date(Web):2017/08/21
DOI:10.1039/C7NJ01478C
A novel and high-performance foldable solid-state supercapacitor has been developed based on nitrogen-containing polyaniline-based carbon nanosphere (C-PANI) coated carbon cloth electrodes and the AQSA-Na (anthraquinone-2-sulfonic acid sodium salt) redox mediator doped PVA (polyvinyl alcohol)–H2SO4 robust gel film electrolyte. The foldable solid-state supercapacitor demonstrates outstanding electrochemical performance such as a large specific capacitance of 430 F g−1 at a current density of 0.8 A g−1, a remarkably high energy density of 33.4 W h kg−1 at a power density of 600 W kg−1 and excellent cycling stability with 90% specific capacitance retention after 1000 cycles. Simultaneously, the high flexibility of the as-fabricated solid-state supercapacitor enabled it to work under both normal and folding conditions, and the device could be folded/unfolded repeatedly up to 500 times with only a small capacitance loss of 9%. These results indicate that the as-fabricated solid-state supercapacitor is suitable for highly fold-tolerant high-energy-density energy storage device applications. More importantly, owing to the solid-state and integrated configuration, several supercapacitors can be conveniently interconnected together in series or parallel to improve the output potential or current.
Co-reporter:H.C. Ma, Z.M. Yang, H.Y. Cao, L. Lei, Z.Q. Lei
Dyes and Pigments 2017 Volume 140(Volume 140) pp:
Publication Date(Web):1 May 2017
DOI:10.1016/j.dyepig.2017.01.035
•Multi-functional sensing platform towards CO2 capture, F− detection in aqueous phase.•The CO2 sensing technique could be applied in the rough real application via contact and non-contact modes.•The real visualized exhibitions of sensitive F− detection followed one stimulus, but two responses.The development of CO2-active fluorescent sensors is paramount to the climate assessment. And also, because of the biological and environmental importance, trace detection F− is a great challenge task but very necessary for human daily life. This paper presented a water-soluble fluorescent sensor fabricated by triphenylamine derivative of NBTA3− and quaternary ammonium salt (CTAC), which was further explored as a green and multi-functional sensing platform, and demonstrated excellent CO2 response ability and trace amount of F− recognition with obvious visualized exhibitions. Especially, our research result has potential application in the CO2 sensing by contact and vapor modes. Both of techniques exhibited reliable and sensitive and quick CO2 sensing capability. We hope our research result is of real-time monitoring CO2 in our surroundings.Download high-res image (303KB)Download full-size image
Co-reporter:Guofu Ma;Jindan Li;Kanjun Sun;Hui Peng
Journal of Solid State Electrochemistry 2017 Volume 21( Issue 2) pp:525-535
Publication Date(Web):24 September 2016
DOI:10.1007/s10008-016-3389-y
Nitrogen-doped porous activated carbons have been fabricated through a simple and efficient carbonization method at 700 °C with the waste tea-leaves as carbon precursor and ZnCl2 as activating agent. The average pore size and specific surface area are in the ranges of 2.3–6.6 nm and 10.3 ~ 1143.9 m2 g−1, with the ZnCl2 to tea-leaves weight ratio from 0 to 3. As an electrode material for supercapacitors, the TPACs-2 (the ZnCl2 to tea-leaves weight ratio is 2) which has 3.0 wt% nitrogen content, possesses a large specific capacitance of 296 F g−1 at 0.5 A g−1 and excellent rate capability (74 % retention at 10 A g−1) in 2 mol L−1 KOH. Furthermore, the symmetric supercapacitor fabricated with TPACs-2 electrodes delivers a high energy density of 13.5 Wh kg−1 at a power density of 221 W kg−1 and superior cycle stability (only 9 % loss after 5000 cycles), operating in the wide voltage range of 0–1.8 V in 0.5 mol L−1 Na2SO4 aqueous electrolyte. The results demonstrate TPACs-2 is a promising candidate for the electrode material of supercapacitors.
Co-reporter:Wei Wang, Dan Chai, Jisan Zhang, Shouyuan Xue, ... Ziqiang Lei
Journal of the Taiwan Institute of Chemical Engineers 2017 Volume 80(Volume 80) pp:
Publication Date(Web):1 November 2017
DOI:10.1016/j.jtice.2017.07.017
•Ni5Sm-P/C is developed as an efficient UOR catalyst.•Peak current of Ni5Sm-P/C is over 29 times higher than Ni/C.•Addition of Sm and P contributes to the formation of active NiOOH.A ternary Ni5Sm-P/C electrocatalyst is successfully prepared for urea electrooxidation. Physical characterization reveals that the addition of samarium (Sm) and phosphorus (P) to nickel (Ni) can change the electronic configurations of the Ni5Sm-P/C catalyst, leading to more active form of NiOOH. Electrochemical measurements show that the Ni5Sm-P/C catalyst exhibits exceptionally high activity and good stability for the electrooxidation of urea. Notably, the anodic peak current of Ni5Sm-P/C catalyst is over 1.5 times, 21 times and 29 times higher than that of Ni-P/C, Ni5Sm/C and Ni/C, respectively. The high activity on Ni5Sm-P/C owes to the synergistic contribution among Ni, Sm and P. All results demonstrate that adding metal and non-metallic components into Ni/C catalyst will provide a valuable resource of research and practical application for improving the performance of direct urea fuel cells.Download high-res image (124KB)Download full-size image
Co-reporter:Yumao Kang, Wei Wang, Yanling Pu, Jinmei Li, Dan Chai, Ziqiang Lei
Chemical Engineering Journal 2017 Volume 308(Volume 308) pp:
Publication Date(Web):15 January 2017
DOI:10.1016/j.cej.2016.09.087
•A novel electrocatalyst of Pd-NiOx-P/C is fabricated.•The Pd-NiOx-P/C exhibits high catalytic performance for glycerol oxidation.•Phosphorus and nickel oxide synergistically promote Pd performance.Highly active and durable catalysts are crucial for the development of direct alcohol fuel cells (DAFCs). Herein, a phosphorus and nickel oxide co-existed composite catalyst (Pd-NiOx-P/C) is prepared for glycerol electrooxidation in alkaline media. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis reveal that the phosphorus and nickel oxide are co-existed in the Pd-NiOx-P/C composite catalyst. Compared with Pd/C catalyst, electrochemical measurements present that it has good electrocatalytic performance with higher electrochemically active surface area (EASA = 576.3 cm2 mg−1Pd), larger peak current (Ip = 0.3640 A mg−1Pd) and lower activation energy (Ea = 21 kJ mol−1). More importantly, the Pd-NiOx-P/C exhibits high stability. It will be a promising Pd-based catalyst in DAFCs.Download high-res image (108KB)Download full-size image
Co-reporter:Zhiwang Yang, Xueqing Xu, Xixi Liang, Cheng Lei, Yuhan Cui, Wenhua Wu, Yaoxia Yang, Zhe Zhang, Ziqiang Lei
Applied Catalysis B: Environmental 2017 Volume 205(Volume 205) pp:
Publication Date(Web):15 May 2017
DOI:10.1016/j.apcatb.2016.12.012
•A heterojunction MIL-125/Ag/C3N4 nanocomposite was implemented as an efficient visible-light response photocatalysts.•Ag nanoparticles (NPs) were photodeposited on the surface of g-C3N4 and MIL-125 to increase visible-light absorption and reducing the recombination of electron-holes.•MIL-125/Ag/C3N4 nanocomposite is efficient visible-light response photocatalysts for the photoreduction of nitrocompounds in the green catalytic routes.•MIL-125/Ag/C3N4 nanocomposite is efficient visible-light response photocatalysts for the photoxidation of alcohols in the O2 atmosphere and ambient temperature.Photocatalytic synthesis using visible light is a desirable chemical process because of its potential to utilize sunlight. A heterostructured MIL-125/Ag/g-C3N4 nanocomposite was implemented as an efficient bifunctional visible-light response catalyst for the photoreduction of nitrocompounds and the oxidation of alcohols. The photocatalyst was prepared via an accessible method and characterized by XRD, SEM, TEM, XPS, FT-IR, N2 adsorption–desorption isotherm, UV–vis DRS, PL and EIS. The reactive efficiency of the photocatalyst depends on two primary factors, one is the light adsorption of catalysts, Ag nanoparticles (NPs) were photodeposited on the surface of g-C3N4 and MIL-125 to increase visible-light absorption via the surface plasmon resonance. And the other is the separation efficiency of the photogenerated charge carrier. As an electron-conduction bridge in the interface between MIL-125 and g-C3N4, Ag NPs could facilitate the direct migration of photoinduced electrons from g-C3N4 to MIL-125 and retard the recombination of electron-holes. Therefore, the MIL-125/Ag/g-C3N4 sample shows highest photocatalytic activity compared with MIL-125, g-C3N4, MIL-125/Ag and MIL-125/g-C3N4. A corresponding photocatalytic mechanism of these reactions was discussed in detail. Moreover, the photoreduction of nitrocompounds and oxidation of the alcohols with superior conversions and selectivities were obtained, and the catalyst can be recycled four times. It is concluded that MIL-125/Ag/g-C3N4 would be a promising visible light photocatalyst in the field of selective organic transformations.A heterojunction MIL-125/Ag/g-C3N4 nanocomposite was implemented as an efficient visible-light response photocatalysts for the photoreduction of nitrocompounds and oxidation of the alcohols with superior conversions and selectivities. Ag nanoparticles (NPs) were photodeposited on the surface of g-C3N4 and MIL-125 to increase visible-light absorption via the surface plasmon resonance. Moreover, as an electron-conduction bridge, in the interface between MIL-125 and g-C3N4, it is facilitate the direct migration of photoinduced electrons from g-C3N4 to MIL-125, which is conductive to retarding the recombination of electron-holes. Therefore, the MIL-125/Ag/g-C3N4 sample shows highest photocatalytic compared with the MIL-125, g-C3N4, The MIL-125/Ag and MIL-125/g-C3N4. Moreover, catalyst can be recycled four times for the photoreduction of nitrocompounds and oxidation of the alcohols. It is concluded that MIL-125/Ag/g-C3N4 would be an promising visible light photocatalyst in the field of selective organic transformations.Download high-res image (156KB)Download full-size image
Co-reporter:Lei Lei, Hengchang Ma, Yanfang Qin, Manyi Yang, Yucheng Ma, Tao Wang, Yuan Yang, Ziqiang Lei, Dedai Lu, Xiaolin Guan
Polymer 2017 Volume 133(Volume 133) pp:
Publication Date(Web):20 December 2017
DOI:10.1016/j.polymer.2017.11.030
•Combiningthe pH-responsive PAA with AIE active TPA derivative successfully.•pH-responsive property.•A cytoplasm imaging.Fluorescence imaging, especially specific organelle imaging, has become a significant technology to comprehending cell transplantation, migration, division, fusion, and lysis. In this paper, we designed and synthesized a water soluble and fluorescent polymer named as Poly(AA-TPA-d), which was pH-responsive by the fluorescence channel due to the presence of poly acrylic acid as the polymer backbone. The research results demonstrated that Poly(AA-TPA-d) exhibits novel aggregation-induced-emission (AIE) property. Additionally, due to the hydrogen bond formation and C=O···π interactions between methyl acrylate groups, Poly(AA-TPA-d) was of excellent hydrogel formation ability. Moreover, Poly(AA-TPA-d) displayed good bio-compatibility with the living MPC5 cells and highly specific cytoplasm-targeting ability by MTT assay and cell staining experiment respectively.Download high-res image (275KB)Download full-size image
Co-reporter:Dan Chai, Wei Wang, Fengxia Wang, Wangli Jing, ... Ziqiang Lei
International Journal of Hydrogen Energy 2017 Volume 42, Issue 15(Volume 42, Issue 15) pp:
Publication Date(Web):13 April 2017
DOI:10.1016/j.ijhydene.2016.12.139
•Heterogeneous Ir3Sn–CeO2/C is prepared as alternative Pt-free electrocatalyst.•Strong synergistic effect among Ir, Sn and CeO2 is related to the high performance.•Each constitutive component of this catalyst is stable in acidic conditions.For reducing the Pt usage and driving down the cost of fuel cells, it is urgent to develop alternative Pt-free catalysts with high catalytic performance. In this study, an Ir3Sn–CeO2/C heterogeneous catalyst is designed as low-price, alternative Pt-free electrocatalyst towards ethanol oxidation reaction (EOR) in acidic conditions. Owing to the strong synergistic effect among Ir, Sn and CeO2 components, Ir3Sn–CeO2/C heterogeneous catalyst exhibits higher catalytic activity and stability for EOR in comparison with commercial Pt/C, as-prepared Ir/C and Ir3Sn/C. Additionally, kinetics and mechanisms of EOR are also investigated. It proves that ethanol electrooxidation on Ir3Sn–CeO2/C catalyst is a diffusion controlled irreversible process. Meanwhile, the H2SO4 and ethanol concentrations can affect the EOR activity. All results demonstrate Ir3Sn–CeO2/C heterogeneous catalyst is a promising Pt-free choice for EOR.Download high-res image (280KB)Download full-size image
Co-reporter:Hua Xie, Xiao-Qiang Yao, Heng-Chang Ma, Zi-Qiang Lei, Jia-Cheng Liu
Inorganic Chemistry Communications 2017 Volume 80(Volume 80) pp:
Publication Date(Web):1 June 2017
DOI:10.1016/j.inoche.2017.03.037
•A pillar-layered-like MOF has been synthesized by a V-shaped bis-pyridyl ligand.•The symmetric N-donor ligand OPY adopts two different coordination modes.•The complex possesses high thermal stability.Solvothermal assembly of Co2 + ion, a V-shaped bis-pyridyl ligand with two different coordination modes and a tripodal multicarboxylate ligand yields a complicated 3D metal-organic framework, namely [Co(OPY)1.5(Hbtc)]n (1), [OPY = 4,4′-(oxybis(4,1-phenylene))dipyridine and H3btc = trimesic acid]. The compound 1 has been characterized by IR, elemental analysis, single crystal X-ray diffraction, XRD and TG analysis. Magnetic measurements performed on 1 indicate the occurrence of weak antiferromagnetic coupling between the neighboring Co2 + ions. In addition, the compound shows high thermal stability.A dinuclear Co based 3D framework has been synthesized by a semi-rigid V-shaped ligand and tripodal multicarboxylate ligand. The OPY ligand adopting two different coordination modes not only expands the dinuclear cobalt chain to a 3D CdSO4-type framework, but also enhance the stability of complex 1.Download high-res image (392KB)Download full-size image
Co-reporter:Wei Wang, Yinjuan Dong, Li Xu, Wenkui Dong, Xiaobo Niu, Ziqiang Lei
Electrochimica Acta 2017 Volume 244(Volume 244) pp:
Publication Date(Web):1 August 2017
DOI:10.1016/j.electacta.2017.05.078
•Novel Se-functionalized Se-C support is developed.•Synergy exists between Se-C support and Pd3Sn alloy NPs.•Obtained Pd3Sn/Se-C has favorable GOR performance.To combine with the advantages of selenium functionalized carbon and bimetallic-alloy nanoparticles (NPs), a novel Se-C supported Pd3Sn (Pd3Sn/Se-C) electrocatalyst was successfully prepared and estimated towords glucose oxidation reaction (GOR) in alkaline medium. The results demonstrate that Pd3Sn/Se-C electrocatalyst possesses superior catalytic performance towards GOR. Specifically, it presents larger electrochemically active surface area, higher electrocatalytic activity and better cycling stability compared to those of Pd3Sn/C, Pd/Se-C and Pd/C. This satisfactory result mainly owes to the special properties of Se-functionalized carbon material, as well as the synergetic effect between Pd3Sn NPs alloy and Se-C support. Additionally, the effects of the concentration of electrolyte and glucose as well as the temperature on the activity for GOR have been investigated. This work will shed new light on the investigation of excellent Se-functionalized-support based electrocatalysts in the future.Download high-res image (160KB)Download full-size image
Co-reporter:Zhiwang Yang, Xueqing Xu, Xixi Liang, Cheng Lei, Lihong Gao, Ruoxue Hao, Dedai Lu, Ziqiang Lei
Applied Surface Science 2017 Volume 420(Volume 420) pp:
Publication Date(Web):31 October 2017
DOI:10.1016/j.apsusc.2017.05.158
•Ce-doped UiO-66/graphene nanocomposite is an efficient visible-light response photocatalysts for the photoreduction of nitrocompounds in the green catalytic routes.•The process of photoreduction for nitrocompounds could be a super strategy degradation of pollutants, and make the nitrocompounds translate into the useful Amine compounds.•Besides, in this study the Ce-doped UiO-66/graphene nanocomposites could efficiently improve the photocatalytic activity of UiO-66.This study investigates the photocatalytic reduction of nitroaromatic compounds upon visible light over novel Ce-doped UiO-66/graphene nanocomposites. Ce doped UiO-66 nanostructures and the corresponding graphene hybridized nanocomposites were facilely synthesized by means of one step solvothermal reaction. It has been demonstrated that produced nanocomposites could be used as highly efficient and chemical stable photocatalysts for the reduction of nitroaromatic compounds under visible irradiation and ambient conditions. Compared with the bare UiO-66, Ce-UiO-66/GR distinctly enhanced photocatalytic activity. Ce as “mediator” introduced into the MOFs materials can greatly improve the electron transfer across the interface between grephene and the UiO-66 and further improve the visible light driven photoactivity. This is an effective strategy for the development of high photocatalytic activity MOFs based materials.Ce doped UiO-66 nanostructures and the corresponding graphene hybridized nanocomposites were facilely synthesized by means of one step solvothermal reaction. It has been demonstrated that produced nanocomposites could be used as highly efficient and chemical stable photocatalysts for the reduction of nitroaromatic compounds under visible irradiation and ambient conditions. Compared with the bare UiO-66, Ce-UiO-66/GR distinctly enhanced photocatalytic activity. Ce as “mediator” introduced into the MOFs materials can greatly improve the electron transfer across the interface between grephene and the UiO-66 and further improve the visible light driven photoactivity. This is an effective strategy for the development of high photocatalytic activity MOFs based materials.Download high-res image (281KB)Download full-size image
Co-reporter:Zengming Yang;Hengchang Ma;Zijie Jin;Haiying Cao;Lei Lei;Yucheng Ma
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 4) pp:1637-1644
Publication Date(Web):2017/02/13
DOI:10.1039/C6NJ03915D
It is desirable to engineer bio-compatible construction materials and cargo release vehicles with efficient cargo loading capability and controlled drug delivery ability. Herein, an inorganic–organic hybrid composite DNDT&SiO2–NH2@BSA was established using two steps. Technologically, the fluorescent DNDT was grafted on the particles surface via solid phase synthesis, which was able to report the occurrence of interactions between the silica cores and proteins of bovine serum albumin (BSA) by real-time optical change analysis. It should be noted that the construction method derived from this study can be transposed easily to other surface modification procedures. Interestingly, DNDT&SiO2–NH2@BSA could be dispersed into an aqueous phase very well, leading to a homogeneous distribution of the drug over the matrix with a more efficient manner. Furthermore, due to the temperature-dependent α-helix content changes, the encapsulators of BSA can capture the drugs at low temperature and release them with elevating temperature. In particular, a desirable controlled release is realized at 37 °C.
Co-reporter:Lei Lei;Hengchang Ma;Manyi Yang;Yanfang Qin;Yucheng Ma;Tao Wang;Yuan Yang;Dedai Lu;Xiaolin Guan
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 21) pp:12375-12379
Publication Date(Web):2017/10/24
DOI:10.1039/C7NJ02416A
In this work, we fabricated a novel triphenylamine-derivative (DNDT)-modified nanographene oxide by following a simple gram-scale method. The product showed interesting optical properties and good potential for use in bioimaging applications. This fluorescent carbon material could be readily internalized by HepG2 cells and was clearly visualized to accumulate mainly in the nucleus.
Co-reporter:Enke Feng;Guofu Ma;Hui Peng;Fengting Hua;Wei Tang
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 22) pp:13347-13354
Publication Date(Web):2017/11/06
DOI:10.1039/C7NJ02976D
Compressible supercapacitors are novel energy-storage devices that can be used in elastic electronics; however, the performance of the supercapacitor depends mainly on its electrode materials and configuration. Herein, free-standing three-dimensional hierarchical porous polypyrrole (PPy) wrapped nitrogen-containing polyaniline based carbon nanospheres (NPACNS) are prepared and coated on the skeleton of sponge composite electrodes (PPy/NPACNS/sponge) via dipping and drying and chemical oxidation polymerization methods. Furthermore, an integrated highly compressible all-solid-state supercapacitor is fabricated using PPy/NPACNS/sponge as the electrode and polyvinyl alcohol (PVA)/LiClO4 gel as the electrolyte, which demonstrates an outstanding electrochemical performance of 95 F g−1 (2.8 F cm−3) specific capacitance, 3.3 W h kg−1 (0.1 mW h cm−3) energy density and 93% capacitance retention after 1000 cycles. Surprisingly, the electrochemical performance of the as-fabricated device remains nearly unchanged when it is compressed under 50% strain, and its specific capacitance and compressibility are well maintained after 400 repeated compressing-releasing cycles. More importantly, due to its solid-state and integrated configuration, several compressible supercapacitors can be conveniently interconnected together in series on one chip to power electronics. This device will pave the way for advanced supercapacitor applications in compressible energy storage devices that are compatible with compression-tolerant electronics.
Co-reporter:Hengchang Ma;Zengming Yang;Haiying Cao;Lei Lei;Lu Chang;Yucheng Ma;Manyi Yang;Xiaoqiang Yao;Shaobo Sun
Journal of Materials Chemistry B 2017 vol. 5(Issue 4) pp:655-660
Publication Date(Web):2017/01/25
DOI:10.1039/C6TB02844F
Specific organelle imaging and long-term cellular tracking are of paramount importance in monitoring biological processes, pathological pathways, and therapeutic effects, etc. Herein, we report a novel macromolecule fluorescent probe (TPPA–DBO), which is synthesized from tris(4-(pyridin-4-yl)phenyl)amine (TPPA) and 1,8-dibromononane (DBO) with a gram scale by a simple method. TPPA–DBO demonstrates a highly specific nucleolus-targeting ability, which is very challenging in the bioimaging research field. We have shown that the green nucleolus-specificity probe TPPA–DBO has advantages over the commercially available nucleolus-staining probes such as DAPI, Hoechst dyes and SYTOs in terms of its AIE-performance, large Stokes shift (175 nm), excellent photostability, and promising usefulness in live cell imaging experiments. Surprisingly, after internalizing TPPA–DBO into the nucleus region for a period of time, some TPPA–DBO are reversely diffused from nucleolus into the cytoplasm, thus resulting in the staining of mitochondria with a redder emission color. This research result may provide a new concept of cellular tracker design and provide insight into biological questions, understanding disease mechanismss, and designing new therapeutic strategies.
Co-reporter:Xiaozhong Zhou, Zhengfeng Zhang, Jianwen Wang, Qingtao Wang, Guofu Ma, Ziqiang Lei
Journal of Alloys and Compounds 2017 Volume 699(Volume 699) pp:
Publication Date(Web):30 March 2017
DOI:10.1016/j.jallcom.2016.12.434
•Sb2O4/rGO composite was prepared through a facile one step solvothermal method.•Sb2O4 nanoparticles were uniformly anchored on rGO sheets.•The reduction of GO and oxidation of Sb2O3 to Sb2O4 can be achieved concurrently.•The Sb2O4/rGO composite showed high reversible capacity and good cyclability.Sb2O4/reduced graphene oxide (Sb2O4/rGO) composite was synthesized through a facile one-step solvothermal approach using Sb2O3 and graphene oxide as raw material. Characterization shows that Sb2O4 nanoparticles were uniformly anchored on rGO sheets, and the obtained Sb2O4/rGO composite delivered a high reversible specific capacity of 1170 mA h g−1 and a good cyclability of 798 mA h g−1 after 200 cycles at a current of 100 mA g−1 when used as a candidate anode material for lithium-ion batteries, benefiting from the enhanced electrochemical activity of Sb2O4 nanoparticles, the maximum utilization of conductive rGO sheets, and also the synergistic effect between them.
Co-reporter:Wei Wang, Shijia Liu, Yanqin Liu, Wangli Jing, ... Ziqiang Lei
International Journal of Hydrogen Energy 2017 Volume 42, Issue 43(Volume 42, Issue 43) pp:
Publication Date(Web):26 October 2017
DOI:10.1016/j.ijhydene.2017.09.024
•Chitosan is used to fabricate carbon material (PR-C).•The advantages of nitrogen-doping and pores are combined in PR-C.•PR-C (1:3.5) exhibits favorable performance in ORR.Developing non-precious catalysts with high activity and superior durability is eager demand for the wide spread fuel cells. In this study, a novel kind of nitrogen-doping carbon based material (PR-C) has been fabricated with phenolic resin and chitosan, in which the low-cost and renewable biomass material chitosan is used as the nitrogen source. Notably, compared with Pt/C, among the resultant catalysts, the PR-C (1:3.5) catalyst has long-term stability, superior tolerance to methanol poisoning, and favorable electrocatalytic activity for oxygen reduction reaction (ORR). Consequently, as-prepared catalyst (PR-C) utilized phenolic resin/chitosan is promising as a low-cost and renewable catalyst for ORR.The PR-C prepared from phenolic resin/chitosan exhibits durable and anti-poisoning performance for ORR.Download high-res image (208KB)Download full-size image
Co-reporter:Hengchang Ma;Haiying Cao;Lei Lei;Zengming Yang;Manyi Yang;Yanfang Qin;Yucheng Ma;Xiaolin Guan;Dedai Lu
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 16) pp:7908-7914
Publication Date(Web):2017/08/07
DOI:10.1039/C7NJ01407D
The effective polymerization process is very desirable in the field of macromolecule science. In this study, we present a facile synthetic method via aldol addition and condensation (AAC) that leads to the formation of fluorescent linear and branched polymers by cross coupling triphenylamines (TPA) and cyclohexanones (CYC) via CC bond formation. The methodology has the advantage of easy operations, mild reaction conditions, and high yield. Via the analysis of NMR, FT-IR, GPC, PL, UV, SEM, and theoretical calculation, the structure, physical properties, and optical behaviors of both polymers were well-characterized. The understanding of cell transplantation, migration, division, fusion, and lysis is a very challenging task. In this study, the linear polymer (LP) exhibits excellent biocompatibility and low cytotoxicity, which can be readily internalized by living cells in a noninvasive manner. The images of MPC5 cells indicate that LP can be a promising emissive fluorescence probe for bioimaging application.
Co-reporter:Hengchang Ma, Chunxuan Qi, Chao Cheng, Zengming Yang, Haiying Cao, Zhiwang Yang, Jinhui Tong, Xiaoqiang Yao, and Ziqiang Lei
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 13) pp:8341
Publication Date(Web):March 11, 2016
DOI:10.1021/acsami.5b11091
There is a great demand to understand cell transplantation, migration, division, fusion, and lysis. Correspondingly, illuminant object-labeled bioprobes have been employed as long-term cellular tracers, which could provide valuable insights into detecting these biological processes. In this work, we designed and synthesized a fluorescent polymer, which was comprised of hydrophilic N-isopropylacrylamide polymers as matrix and a hydrophobic tetraphenylethene (TPE) unit as AIE-active cross-linkers (DDBV). It was found that when the feed molar ratio of N-isopropylacrylamides to cross-linkers was 22:1, the produced polymers demonstrated the desirable LCST at 37.5 °C. And also, the temperature sensitivity of polymers could induce phase transfer within a narrow window (32–38 °C). Meanwhile, phase transfer was able to lead the florescent response. And thus, we concluded that two responses occur when one stimulus is input. Therefore, the new cross-linker of DDBV rendered a new performance from PNIPAm and a new chance to create new materials. Moreover, the resulted polymers demonstrated very good biocompatibility with living A549 human lung adenocarcinoma cells and L929 mouse fibroblast cells, respectively. Both of these cells retained very active viabilities in the concentration range of 7.8–125 μL/mg of polymers. Notably, P[(NIPAm)22–(DDBV)1] (P6) could be readily internalized by living cells with a noninvasive manner. The cellular staining by the fluorescent polymer is so indelible that it enables cell tracing for at least 10 passages.Keywords: aggregation-induced emission (AIE); long-term cellular tracing; poly(N-isopropylacrylamide) (PNIPAm); tetraphenylethene (TPE); thermosensitive
Co-reporter:Hui Lv, Qi Xing, Chengtao Yue, Ziqiang Lei and Fuwei Li
Chemical Communications 2016 vol. 52(Issue 39) pp:6545-6548
Publication Date(Web):15 Apr 2016
DOI:10.1039/C6CC01234E
An unprecedented catalyst-free formylation of amines using CO2 and hydrosilanes was developed. The solvent plays a vital role in promoting the interaction of amines with hydrosilanes and subsequent CO2 insertion, thus facilitating the simultaneous activation of N–H and Si–H bonds. Based on relevant mechanistic studies, a plausible mechanism involving a silyl carbamate intermediate is proposed.
Co-reporter:Dan Chai, Wei Wang, Fengxia Wang, Yumao Kang, Yan Yang, Ziqiang Lei
Electrochimica Acta 2016 Volume 189() pp:295-302
Publication Date(Web):20 January 2016
DOI:10.1016/j.electacta.2015.12.071
•Prepared Pd-SnCoOx/C catalyst via precipitation and polyol methods.•Pd-SnCoOx/C catalyst shows high performance for glucose oxidation.•Concluded synergistic effect between Sn-Co oxide and Pd nanoparticles.•Investigated the effects of concentrations and scan rates.To improve the electrocatalytic activity of Pd for glucose oxidation, a novel binary Sn-Co oxide promoting Pd catalyst (Pd-SnCoOx/C) is synthesized via facile precipitation and polyol methods. Electrochemical results show that Pd-SnCoOx/C exhibits excellent electrocatalytic performance for glucose oxidation. Compared with Pd/C catalyst, as-prepared Pd-SnCoOx/C catalyst has larger electrochemically active surface area, higher electrochemical activity and superior stability. The high catalytic performance may be attributed to the synergistic effect between binary Sn-Co oxide and Pd nanoparticles, leading to smaller size and higher dispersion for Pd-SnCoOx/C than Pd/C. To further understand the glucose oxidation, the tafel plots, effects of concentrations and scan rates are also investigated.
Co-reporter:Yanqin Liu, Wei Wang, Fengxia Wang, Yan Yang, Dan Chai and Ziqiang Lei
New Journal of Chemistry 2016 vol. 40(Issue 2) pp:1633-1639
Publication Date(Web):30 Nov 2015
DOI:10.1039/C5NJ02148K
Carbonized 1H-benzotriazole modified carbon (BTA-MC) is prepared, then Pd nanoparticles are deposited on to it (Pd/BTA-MC). The BTA modification leads to good Pd dispersion and strengthened interaction between Pd and BTA-MC, so the prepared Pd/BTA-MC catalyst has an enhanced electrochemical performance towards ethanol oxidation in alkaline media. Compared to a conventional Pd/C catalyst, the Pd/BTA-MC catalyst exhibits a larger electrochemically active surface area, higher electrocatalytic activity and better poison-tolerance, as well as a lower apparent activation energy. It would be a promising candidate for direct ethanol fuel cells.
Co-reporter:Wei Wang, Yumao Kang, Yan Yang, Yanqin Liu, Dan Chai, Ziqiang Lei
International Journal of Hydrogen Energy 2016 Volume 41(Issue 2) pp:1272-1280
Publication Date(Web):12 January 2016
DOI:10.1016/j.ijhydene.2015.11.017
•Phenanthroline-functionalized carbon immobilizes PdSn nanoparticles.•Glycerol electrooxidation is explored on the PdxSny/phen-C catalysts.•Pd3Sn/phen-C displays the high performance.Functionalized carbon is an effective material to immobilize nanoparticles for producing high efficient electrocatalysts. In this paper, phenanthroline is used to direct functionalize carbon (phen-C), and different molar ratios of PdSn (Pd:Sn = 1:1–1:3) nanoparticles are deposited subsequently. According to the electrochemical results, the Pd3Sn/phen-C catalyst has the largest electrochemically active surface area (577.2 cm2 mg−1Pd), best activity and stability among as-prepared PdxSny/phen-C, Pd/phen-C and Pd/C catalysts for glycerol oxidation. Furthermore, the durability and poisoning tolerance of Pd3Sn/phen-C are also superior to that of Pd/C. The Pd3Sn/phen-C would be a potential electrocatalyst for glycerol oxidation.
Co-reporter:Ma Hengchang, Yang Zengming, Cao Haiying, Lei Lei and Lei Ziqiang
RSC Advances 2016 vol. 6(Issue 73) pp:69404-69411
Publication Date(Web):07 Jul 2016
DOI:10.1039/C6RA14391A
Signal amplification, known as the “molecular wire” effect, is greatly desirable and achieved by the electrostatic interactions of aminated SiO2 nanoparticles (SiO2–NH2) with acidic fluorescent partners (NBTA). This explored sensing platform exhibited a multi-responsive capability toward external stimuli, including that of TFA/Et3N, chloroauric acid, as well as the explosive compound PA.
Co-reporter:Qiangbing Wei, Ruirong Shi, Dedai Lu and Ziqiang Lei
RSC Advances 2016 vol. 6(Issue 35) pp:29245-29253
Publication Date(Web):15 Mar 2016
DOI:10.1039/C6RA02789J
In this study, we present a simple and green approach to fabricate a magnetic halloysite nanotube (MHNT) supported Au nanoparticle (NP) composite (MHNTs–PDA–Au) with a polydopamine functional coating for highly effective and recyclable catalysis. The fabrication of MHNTs–PDA–Au involves decoration of Fe3O4 NPs on HNTs via a one-step co-precipitation method, deposition of a polydopamine layer on the MHNTs and subsequent in situ reduction of Au NPs via polydopamine chemistry. All the processes are simple and eco-friendly without use of additional toxic reagents and complicated treatment. The obtained MHNTs–PDA–Au composite exhibits excellent and versatile catalytic activity toward the reduction of various nitrobenzene derivatives and methylene blue dye when only trace amounts of Au catalyst are used. In addition, the catalytic system can be easily recycled for several cycles based on its good magnetic properties. The synergistic combination of MHNTs, polydopamine coating and metal NPs offers a versatile platform for design of natural HNT based composite materials and will expand the applications of HNTs in heterogeneous catalysis, water purification and green chemistry.
Co-reporter:Wei Wang, Yan Yang, Yanqin Liu, Fengxia Wang, Yumao Kang, Ziqiang Lei
International Journal of Hydrogen Energy 2016 Volume 41(Issue 1) pp:300-306
Publication Date(Web):5 January 2016
DOI:10.1016/j.ijhydene.2015.10.101
To improve the electrochemical performance of Pd-based catalysts for ethylene glycol oxidation (EGOR), a series of dealloyed Pdx(FeCo)10–x/C (Pd:FeCo = 3:7–9:1) catalysts have been synthesized by dealloying process in acid solution. The electrocatalytic results show that the electrocatalytic performances of D-Pdx(FeCo)10–x/C catalysts are increased as FeCo compositions increasing. And the further increased FeCo compositions would decrease the performances. That is, the Pd:FeCo = 6:4 is the optimal composition among the various precursor atomic ratios. For the interaction between surface Pd atoms and sub-layer alloyed Fe and Co atoms, the dealloyed Pd6(FeCo)4/C (D-Pd6(FeCo)4/C) catalyst has enhanced electrocatalytic performance. The peak current of D-Pd6(FeCo)4/C is 1.20 times than that of Pd/C in EGOR. And in the chronoamperometric tests, the current decreased rate of D-Pd6(FeCo)4/C is lower than that of Pd/C catalyst.
Co-reporter:Xiaolin Guan;Hongting Fan;Tianming Jia;Donghai Zhang;Yang Zhang;Shoujun Lai
Macromolecular Chemistry and Physics 2016 Volume 217( Issue 5) pp:664-671
Publication Date(Web):
DOI:10.1002/macp.201500323
Co-reporter:Guofu Ma;Zhiguo Zhang;Hui Peng;Kanjun Sun
Journal of Solid State Electrochemistry 2016 Volume 20( Issue 6) pp:1613-1623
Publication Date(Web):2016 June
DOI:10.1007/s10008-016-3171-1
In this work, the micromolecule l-glutamic acid (Glu) is employed as nitrogen-rich precursor to prepare a novel porous carbon, and ZnCl2 is used as activating agent to improve the surface area and electrochemical performance of the carbon. The nitrogen content of the carbon (Glu-2.5) prepared by Glu and ZnCl2 with a mass ratio of 1:2.5 retains as high as 7.1 % at an activation temperature of 700 °C. The surface area and pore volume of Glu-2.5 are 1007.4 m2 g−1 and 0.57 cm3 g−1, respectively. Glu-2.5 exhibits a high specific capacitance of 330.6 F g−1 in 2 M KOH electrolyte at the current density of 1 A g−1and good cycling stability (89 % retention of capacitance after 5000 charge/discharge cycles). More importantly, the assembled symmetric supercapacitor using Glu-2.5 as electrodes reveals a high energy density (16.7 Wh kg−1) under the power density of 404.7 W kg−1. Owing to its inherent advantages, Glu-2.5 could be a promising and scalable alternative applied to energy storage/conversion.
Co-reporter:Xiaozhong ZhouZhengfeng Zhang, Xiaohu Xu, Jian Yan, Guofu Ma, Ziqiang Lei
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 51) pp:
Publication Date(Web):December 7, 2016
DOI:10.1021/acsami.6b13548
Sb6O13/reduced graphene oxide (Sb6O13/rGO) nanocomposite was synthesized by the solvothermal method using Sb2O3 and graphene oxide as raw material. On the basis of the physical and electrochemical characterizations, Sb6O13 nanocrystals of 10–20 nm size were uniformly anchored on rGO sheets, and the nanocomposite displayed a large reversible specific capacity of 1271 mA h g–1 and an excellent cyclability of 1090 mA h g–1 after 140 cycles at 100 mA g–1 when proposed as a potential anode material for lithium ion batteries, emphasizing the advantages of anchoring of Sb6O13 nanocrystals on rGO sheets for the maximum utilization of electrochemically active Sb6O13 and rGO for lithium storage.Keywords: antimony hexitatridecoxide (Sb6O13); excess lithium storage; lithium ion batteries; reduced graphene oxide (rGO); reversible conversion alloying;
Co-reporter:Q. T. Wang;R. R. Li;X. Z. Zhou;J. Li
Journal of Solid State Electrochemistry 2016 Volume 20( Issue 5) pp:1331-1336
Publication Date(Web):2016 May
DOI:10.1007/s10008-016-3127-5
Herein, a new polythiophene-coated silicon composite anode material was prepared by in situ chemical oxidation polymerization method. The structure of this material was characterized by infrared spectroscopy, which proved that the oxidative polymerization of thiophene occurred mainly in α position. The polythiophene can provide the better electric contact between silicon particles. Therefore, the as-prepared Si/polythiophene composite electrodes achieve better cycling performance than the bare Si anode. The specific capacity of the composite electrode retains 478 mA h g−1 after 50 cycles.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Zhiguo Zhang, Qian Yang, Feitian Ran and Ziqiang Lei
Journal of Materials Chemistry A 2015 vol. 3(Issue 25) pp:13210-13214
Publication Date(Web):21 May 2015
DOI:10.1039/C5TA03034J
Highly crumpled nitrogen-doped graphene-like nanosheets (CN-GLSs) with a high specific surface area (1169 m2 g−1) and large pore volume (2.58 cm3 g−1) are prepared from a macroporous resin via simultaneous urea gasification expansion and CaCl2 activation methods. The CN-GLSs are tested as electrodes for supercapacitors and present excellent electrochemical performance.
Co-reporter:Guofu Ma, Miaomiao Dong, Kanjun Sun, Enke Feng, Hui Peng and Ziqiang Lei
Journal of Materials Chemistry A 2015 vol. 3(Issue 7) pp:4035-4041
Publication Date(Web):06 Jan 2015
DOI:10.1039/C4TA06322H
A stable and effective redox-mediator gel electrolyte has been prepared by doping indigo carmine (IC) into a polyvinyl alcohol sulfuric acid polymer system (PVA–H2SO4), and a high performance solid state supercapacitor is fabricated by utilizing activated carbon as electrodes and the prepared gel polymer (PVA–H2SO4–IC) as an electrolyte and separator. The PVA–H2SO4–IC gel polymer has excellent bending, compressing and stretching mechanical properties. As expected, the ionic conductivity of the gel polymer electrolyte increased by 188% up to 20.27 mS cm−1 while introducing IC as the redox mediator in the PVA–H2SO4 gel electrolyte. Simultaneously, specific capacitance is increased by 112.2% (382 F g−1) and energy density (13.26 W h kg−1) is also increased. Furthermore, the fabricated device shows superior charge–discharge stability. After 3000 cycles, its capacitive retention ratio is still as high as 80.3%. This result may be due to the fact that the IC can act as a plasticizer and redox mediator, and the supercapacitor combines the double-layer characteristic of carbon-based supercapacitors and the faradaic reaction characteristic of batteries energy-storage processes.
Co-reporter:Lijun Shi, Xiang Zhong, Houde She, Ziqiang Lei and Fuwei Li
Chemical Communications 2015 vol. 51(Issue 33) pp:7136-7139
Publication Date(Web):16 Mar 2015
DOI:10.1039/C5CC00249D
The Mn-catalyzed C–H alkenylation reactions of indole with terminal- and internal-alkynes have been developed. In the presence of a catalytic amount of acid, the procedure efficiently affords bis/trisubstituted indolyl-alkenes in a highly regio- and stereo-selective manner. Without the addition of acid, the reaction undergoes a [2+2+2] cyclization process to give carbazoles with release of hydrogen gas. Notably, the directing pyrimidyl group can be readily removed. Experimental studies reveal that the reaction is initiated by a C–H activation step and the acid is the selectivity controller via a hydrogen transfer process.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Zhiguo Zhang, Jindan Li, Xiaozhong Zhou, Ziqiang Lei
Journal of Power Sources 2015 Volume 297() pp:351-358
Publication Date(Web):30 November 2015
DOI:10.1016/j.jpowsour.2015.08.025
•Asymmetric supercapacitor is assembled based on novel Co0.85Se and N-PCNs electrodes.•Petal-like Co0.85Se nanosheets are synthesized via a simple solvothermal method.•N-PCNs are prepared by integrating polymerization and catalytic carbonization method.•Co0.85Se//N-PCNs aqueous ASC with an extended operating voltage window of 1.6 V.•The ASC exhibits a high energy density, high rate ability and good cycle stability.A novel asymmetric supercapacitor (ASC) is assembled based on petal-like cobalt selenide (Co0.85Se) nanosheets as positive electrode and nitrogen-doped porous carbon networks (N-PCNs) as negative electrode in a 2 M KOH aqueous electrolyte. The Co0.85Se nanosheets are synthesized via a simple low-temperature solvothermal method without any template and surfactant, and the N-PCNs are prepared by integrating in-situ oxidation polymerization and catalytic carbonization methods directly from the p-phenylenediamine monomers. Thanks to their unique structures and high capacitive performance, the as-assembled Co0.85Se//N-PCNs ASC device possesses an extended operating voltage window of 1.6 V, high energy density of 21.1 W h kg−1 at a power density of 400 W kg−1 and outstanding cycling stability (93.8% capacitance retention after 5000 cycles) in aqueous electrolyte.
Co-reporter:Kanjun Sun, Enke Feng, Hui Peng, Guofu Ma, Yajuan Wu, Haiping Wang, Ziqiang Lei
Electrochimica Acta 2015 Volume 158() pp:361-367
Publication Date(Web):10 March 2015
DOI:10.1016/j.electacta.2015.01.185
•The eco-friendly polyaspartic acid is used as a precursor for nitrogen-doped porous carbon.•Redox-mediated Na2MoO4 is introduced in H2SO4 aqueous solution to form mixture electrolyte.•The supercapacitor exhibits high specific capacitance 841 F g−1 and energy density 378.5 Wh kg−1.Nitrogen-doped porous carbon derived from polyaspartic acid is utilized as activated carbon (AC) electrode for supercapacitor. The BET surface area and pore volume of the AC as high as 1071 m2 g−1 and 0.61 cm3 g−1. The AC electrode in 1 M H2SO4 electrolyte delivers high specific capacitance of 177 F g−1 at a high current density of 15 A g−1. Surprisingly, by introducing redox-mediated 0.6 g Na2MoO4 into 40 ml 1 M H2SO4 as a mixture electrolyte, the specific capacitance of the supercapacitor improved 841 F g−1, about 375.1% of specific capacitance in 1 M H2SO4 electrolyte. The high energy density 378.5 Wh kg−1 is also obtained. Furthermore, the AC electrode in the redox active Na2MoO4 electrolyte shows the excellent capacitance retention of 88.2% for over 1000 cycles. These improved performance are owed to the redox reaction between Mo(VI)/Mo(V) and Mo(VI)/Mo(IV) redox couples in the mixed H2SO4 and Na2MoO4 electrolyte at the electrode|electrolyte interface, and the concentration of the Na2MoO4 can also influence the electrochemical performance of the supercapacitor. Based on the overall performance, it is believed that the combination of polyaspartic acid derived nitrogen-doped porous carbon and redox active Na2MoO4 electrolyte is more attractive in the near future for high performance energy-storage devices.
Co-reporter:Wei Wang, Dan Chai, Yan Yang, Yanqin Liu, Yumao Kang, Ziqiang Lei
International Journal of Hydrogen Energy 2015 Volume 40(Issue 32) pp:10041-10048
Publication Date(Web):24 August 2015
DOI:10.1016/j.ijhydene.2015.05.190
•Synthesized different Fe–Co hybrid oxides promoted Pd electrocatalysts.•Fe2CoOx intimately contacts to Pd, leading to SMSI and enhanced catalytic performance.•Investigated effects of EG and KOH concentration, temperature and scan rate.To improve the electrocatalytic performance of Pd for ethylene glycol oxidation reaction (EGOR), Fe–Co hybrid oxides promoted Pd electrocatalysts with different compositions (Pd–Fe2CoOx/C, Pd–FeCoOx/C and Pd–FeCo2Ox/C) are prepared. Electrochemical results show that the Fe–Co hybrid oxides promoted Pd catalysts exhibit high electrocatalytic performance, including large electrochemical active surface area, high activity and good stability towards EGOR. Additionally, it is also found that, Pd–Fe2CoOx/C has the best performance among the as-prepared catalysts. The high electrocatalytic performance could be attributed to the intimate contact of Fe–Co oxides and Pd nanoparticles, according to physical characterizations, which lead to strong interfacial interaction. Moreover, the effects of ethylene glycol and KOH concentration, scan rate and temperature on EGOR activity also have been discussed.
Co-reporter:Guofu Ma, Zhiguo Zhang, Kanjun Sun, Hui Peng, Qian Yang, Feitian Ran and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 130) pp:107707-107715
Publication Date(Web):01 Dec 2015
DOI:10.1039/C5RA20327A
We have employed the biomaterial white clover as a carbon precursor and ZnCl2 as an activating agent to prepare white clover carbons (WCCs). The WCC-2 (mass ratios of white clover and ZnCl2 is 1:2) possesses as high as 6.9 wt% nitrogen content and 857 m2 g−1 BET surface area. Furthermore, it exhibits 233.1 F g−1 specific capacitance at a current density of 1.0 A g−1, even 82.9% capacitance retention at 20 A g−1 in 2 mol L−1 KOH electrolyte. The specific capacitance could remain at almost about 100.0% when the cycle number is between the 200–5000 cycles. Because of the wide potential window (0–2.0 V) and high specific capacitance, the WCC-2//WCC-2 symmetric capacitor shows an energy density of 30–13.1 W h kg−1 under the power outputs of 503.5–9991.5 W kg−1 in 0.5 mol L−1 Na2SO4 electrolyte. The results demonstrate WCC-2 can be a promising candidate for the electrode material of high performance supercapacitors.
Co-reporter:Ma Hengchang, Zhang Zhongwei, Jin Yuanyuan, Zha Lajia, Qi Chunxuan, Cao Haiying, Yang Zengming, Yang Zhiwang and Lei Ziqiang
RSC Advances 2015 vol. 5(Issue 106) pp:87157-87167
Publication Date(Web):30 Sep 2015
DOI:10.1039/C5RA12154J
Triphenylamine-decorated BODIPY derivative TBMA was designed and synthesized. Luminogen aggregation was developed by taking advantage of twisted intramolecular charge transfer (TICT) and aggregation-induced emission (AIE) processes. In non-polar solvents, the locally excited (LE) states of BODIPY luminogens emitted intense yellow light. Increasing solvent polarity brought the luminogens from an LE to a TICT state, causing a large bathochromic shift in the emission color and a dramatic decrease in emission efficiency. The red emission was greatly boosted by aggregate formation or AIE effect. We also discovered that TBMA could be applied as an efficient chemical sensor for picric acid (PA) detection. The detection limit and quenching constant (KSV) were determined as 30 ppb and 2.1 × 10−6 M−1 respectively. 19F NMR and 1H NMR titration analysis verified that F⋯H hydrogen bonding is demonstrated as the mode of interaction, which possibly facilitates effective exciton migration.
Co-reporter:Guofu Ma, Feitian Ran, Hui Peng, Kanjun Sun, Zhiguo Zhang, Qian Yang and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 101) pp:83129-83138
Publication Date(Web):25 Sep 2015
DOI:10.1039/C5RA16619E
In this work, we present a facile approach to prepare nitrogen-doped porous carbon materials via one-step carbonizing biowaste soybean curd residue (SCR) as the biomass carbon precursor. The morphology, structure and textural properties of the carbon materials are investigated by field emission scanning electron microscopy, transmission electron microscopy, N2 sorption isotherms, and X-ray photoelectron spectroscopy, respectively. The SCR carbonized at 700 °C exhibits a high charge storage capacity with a specific capacitance of 215 F g−1 at a current density of 0.5 A g−1 and good stability over 5000 cycles. Moreover, the assembled symmetric supercapacitor device possesses a energy density of 9.95 W h kg−1 at a power density of 236 W kg−1, which is higher than that of commercially available supercapacitors. The high supercapacitor performance of the porous carbon can be due to the high surface area and effective nitrogen-doping, indicating it has great potential for supercapacitors.
Co-reporter:Guofu Ma, Dongyang Guo, Kanjun Sun, Hui Peng, Qian Yang, Xiaozhong Zhou, Xiaolong Zhao and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 79) pp:64704-64710
Publication Date(Web):23 Jul 2015
DOI:10.1039/C5RA11179J
Cotton-based porous activated carbons (CACs) are prepared through a simple chemical activation method using cotton fiber as carbon source and ZnCl2 as activating agent. Powder X-ray diffraction, scanning electron microscopy, and N2 adsorption–desorption tests demonstrate that the carbons activated with different amounts of ZnCl2 have a large number of mesopores, notably, a maximum specific surface area of 2548.6 m2 g−1 and ultrahigh pore volume of 1.54 cm3 g−1 for CAC2 sample are obtained when the cotton/ZnCl2 mass ratio is 1:2. As an electrode material for supercapacitors, the CAC2 possesses a high specific capacitance of 239 F g−1 at 0.5 A g−1 and good rate capability (82% capacitance retention even at 8 A g−1) in 2 mol L−1 KOH aqueous electrolyte. Moreover, the as-assembled CAC2//CAC2 symmetric supercapacitor exhibits a high energy density of 13.75 Wh kg−1 at a power density of 225 W kg−1 operated at the voltage range of 0 to 1.8 V in 0.5 mol L−1 Na2SO4 aqueous electrolyte and an excellent cyclability retaining about 93% initial capacitance after 5000 cycles.
Co-reporter:Guofu Ma, Feitian Ran, Qian Yang, Enke Feng and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 66) pp:53819-53828
Publication Date(Web):03 Jun 2015
DOI:10.1039/C5RA07206A
A novel superabsorbent composite with high swelling properties was synthesized by the grafted co-polymerization of partially neutralized acrylic acid (AA) onto a sodium alginate (NaAlg) backbone in the presence of organo-loess. The FTIR spectra, XRD patterns and SEM micrographs prove that the AA monomers were grafted onto the NaAlg backbone, and the organo-loess dispersed into the polymer matrix that improved the porous structure, which was verified by element mapping. TGA and DSC results indicate that the incorporation of loess enhances the thermal stability of the superabsorbent. Swelling results confirm that proper amount of organo-loess in the superabsorbent can enhance the swelling capability and salt-resistant performance. The maximum equilibrium water absorbency of the superabsorbent composite incorporated with 10 wt% organo-loess in distilled water and 0.9 wt% NaCl aqueous solution were 656 g g−1 and 69 g g−1, respectively. Furthermore, the superabsorbent composite exhibited good buffer ability to external pH in the range from 4 to 10 and water retention ability. According to the performance of the eco-friendly superabsorbent composite, it can be used as a promising candidate for applications in various fields.
Co-reporter:Wei Wang, Yan Yang, Fengxia Wang, Wenkui Dong, Xiaozhong Zhou and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 22) pp:17216-17222
Publication Date(Web):03 Feb 2015
DOI:10.1039/C4RA14790A
In this study, a carbonized phenanthroline functionalized carbon support (CPF-C) has been prepared, which was used to load Pt nanoparticles to serve as an electrocatalyst for methanol oxidation. The results show that the performance of Pt in Pt/CPF-C is improved relative to that of industrially adopted Pt/C. The increase is mainly interpreted in terms of the synergistic effect between the stabilized Pt nanoparticles and nitrogen-functionalized CPF-C support. The novel CPF-C support presented here offers an alternative to the conventional carbon support to improve the performance of Pt applied in direct methanol fuel cells.
Co-reporter:Guofu Ma, Haiping Wang, Kanjun Sun, Hui Peng, Yajuan Wu and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 16) pp:12230-12236
Publication Date(Web):08 Jan 2015
DOI:10.1039/C4RA09964H
A novel activated carbon material with a multi-level structure is prepared by KOH-activation of chestnut shells at 800 °C (CAC8). The specific surface area and pore volume of the activated carbon obtained are as high as 1568.0 m2 g−1 and 0.94 cm3 g−1. The electrochemical performance of the CAC8 is very promising; the specific capacitance is 207 F g−1 at a current density of 1 A g−1 in 1 M H2SO4 electrolyte. A CAC8/PANI composite, which was synthesized through an interfacial polymerization method, presents a good electrochemical performance, including an excellent specific capacitance of 597 F g−1 and 80% retention of capacitance after 1000 cycles at a current density of 1 A g−1 in 1 M H2SO4 electrolyte. The high electrochemical performance can be due to the use of the multi-level structured carbon, which improves the charge transfer performance of CAC8/PANI composite materials.
Co-reporter:Yan Yang, Wei Wang, Fengxia Wang, Yanqin Liu, Dan Chai, Ziqiang Lei
International Journal of Hydrogen Energy 2015 Volume 40(Issue 36) pp:12262-12267
Publication Date(Web):28 September 2015
DOI:10.1016/j.ijhydene.2015.07.059
•Providing a partially oxidized (NiFe)x alloy promoter.•Combining the advantages of (NiFe)x alloy and (NiFeO)y oxide to Pd.•Pd-(NiFe)x-(NiFeO)y catalyst exhibits excellent performance for EGOR.In this study, a novel Pd-(NiFe)x-(NiFeO)y/C catalyst is fabricated by supporting Pd on partially oxidized nickel–iron alloy. Because of the promotion effect between nickel–iron alloy and nickel–iron oxide towards Pd, the catalyst exhibits excellent electrocatalytic performance for ethylene glycol oxidation. Specifically, it has much larger electrochemically active surface area, better electrocatalytic activity and durability compared to Pd/C counterpart. After all, this strategy is well suited to synthesize other metal alloys and oxides synergistically promoting Pd electrocatalysts for direct ethylene glycol fuel cells.
Co-reporter:Li Wenfeng, Ma Hengchang, Lu con, Ma Yuan, Qi Chunxuan, Zhang Zhonwei, Yang Zengming, Cao Haiying and Lei ziqiang
RSC Advances 2015 vol. 5(Issue 9) pp:6869-6878
Publication Date(Web):16 Dec 2014
DOI:10.1039/C4RA12025F
A novel triphenylamine-based fluorescent sensor tris((4-amino)phenylduryl)amine (m-TAPA) for Fe3+/Cu2+ ion has been developed. m-TAPA shows high selectivity and sensitivity toward Fe3+/Cu2+ over alkali and transition metal ions in aqueous solution. The possible mechanism of fluorescence quenching was that Fe3+/Cu2+ can be captured by the NH2 groups of m-TAPA to form non-fluorescent complexes, resulting in strong quenching. The detection limits of Fe3+ and Cu2+ were calculated to be 230 nM and 620 nM, respectively. Furthermore, fluorescent test strips have been prepared for convenient detection of Fe3+ and Cu2+ ions in environmental water samples, even in drinking water.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu, Xiaozhong Zhou and Ziqiang Lei
RSC Advances 2015 vol. 5(Issue 16) pp:12034-12042
Publication Date(Web):06 Jan 2015
DOI:10.1039/C4RA11889H
Nitrogen-containing polyaniline-based carbon nanospheres (C-PANI) with diameters of about 200 nm are prepared through a direct carbonization method using polyaniline (PANI) nanospheres as carbon precursors at different temperatures. The PANI nanospheres are synthesized via in situ oxidation polymerization of aniline in the presence of sodium carboxymethyl cellulose as a polymerization template. The C-PANI with 6.69% nitrogen content obtained at 800 °C (C-PANI-800) can achieve a high capacitance of 359 F g−1 at the current density of 1 A g−1 in 6 M aqueous KOH electrolyte, meanwhile maintaining excellent rate capability (81% retention at 20 A g−1). Furthermore, a symmetric supercapacitor fabricated with C-PANI-800 electrodes exhibits an energy density of 17.5 W h kg−1 at a power density of 227 W kg−1 and superior cycle stability (only 4% loss after 5000 cycles), operating in the voltage range of 0–1.8 V in 0.5 mol L−1 Na2SO4 aqueous electrolyte.
Co-reporter:Wei Wang, Yanqin Liu, Wenkui Dong, Yan Yang, Xiaozhong Zhou, Ziqiang Lei
International Journal of Hydrogen Energy 2015 Volume 40(Issue 10) pp:3892-3899
Publication Date(Web):16 March 2015
DOI:10.1016/j.ijhydene.2015.01.109
•Combine the advantages of Pd-alloy and the nitrogen-functioned support in one.•Showed excellent activity and good stability.•Improved utilization of Pd metal.To combine the advantages of Pd3Ni alloy nanoparticles with the nitrogen doped carbon support, a novel electrocatalyst of Pd3Ni nanoparticles supported on carbonized 1,10-phenanthroline modified carbon (PMC) (Pd3Ni/PMC) was fabricated. The Raman results show that the graphitization degree of PMC support is higher than conventional carbon support. And the transmission electron microscopy indicates that the PMC supported Pd3Ni nanoparticles (5.4 nm) with face-centered cubic structure are uniformly dispersed on the carbon surface. The X-ray photoelectron spectroscopy demonstrates that the PdOads is the main component in Pd3Ni/PMC catalyst. Compared to conventional Pd/C and Pd/PMC catalysts, based on Pd mass, the Pd3Ni/PMC catalyst exhibits larger electrochemical surface area, lower onset potential, better electrocatalytic activity and stability for methanol electrooxidation. Kinetic studies also show that the Pd3Ni/PMC has about a half decrease of apparent activation energy compared to Pd/C counterpart for methanol oxidation. These imply that Pd3Ni nanoparticles loaded on PMC support is promising electrocatalyst candidate for direct methanol fuel cells.
Co-reporter:Na Dong, Fangzhen He, Junlian Xin, Qizhao Wang, Ziqiang Lei, Bitao Su
Materials Letters 2015 Volume 141() pp:238-241
Publication Date(Web):15 February 2015
DOI:10.1016/j.matlet.2014.11.054
•CoFe2O4 magnetic fiber nanomaterial was successfully prepared via a template-assisted solvothermal method.•The synthetic strategy is facile environment friendly.•The goal product indicates much higher crystalline degree and has high saturation magnetization.In this work, a novel template-assisted solvothermal method (TASTM) was used to prepare cobalt ferrite (CoFe2O4) magnetic fiber nanomaterial. Cotton fibers (CF) were used as template and Fe(NO3)3·9H2O, Co(NO3)2·6H2O as Fe and Co sources and EtOH as the solvent. XRD result indicates that the sample is single phase of CoFe2O4 with the spinel-type structure. SEM and TEM results reveal that the sample is hollow fibers and the wall is porous. The magnetic measurements result demonstrates that the sample shows enhanced magnetic property. These experimental results suggest that the template CF play an important role in the formation, crystalline structure, morphology and magnetic property of CoFe2O4. The synthesis is simple, low-cost and environment-friendly.
Co-reporter:Guofu Ma;Feitian Ran;Enke Feng;Zhibao Dong
Water, Air, & Soil Pollution 2015 Volume 226( Issue 7) pp:
Publication Date(Web):2015 July
DOI:10.1007/s11270-015-2490-7
A novel and eco-friendly xanthan gum-g-poly(acrylic acid)/laterite (XG-g-PAA/laterite) organic-inorganic composite polymer used as chemical sand-fixing agent (CSFA) was successfully prepared by grafted copolymerization of natural XG, partially neutralized acrylic acid (NaA), and laterite in solution. FTIR spectra confirmed that NaA had been grafted onto XG chains, and the –OH groups of laterite participated in polymerization reaction. The influence of the content of CSFA on sand-fixing effect was investigated, and the results of the aging test indicated that the CSFA had remarkable water resistance, heat resistance, anti-freeze-thaw, and anti-ultraviolet aging performances, which could meet the requirement of application in the harsh desert environment. Moreover, it also showed excellent water-retaining and anti-evaporation properties.
Co-reporter:Yuan Ma, Hengchang Ma, Zenming Yang, Jun Ma, Yuhu Su, Wenfeng Li, and Ziqiang Lei
Langmuir 2015 Volume 31(Issue 17) pp:4916-4923
Publication Date(Web):April 15, 2015
DOI:10.1021/acs.langmuir.5b00275
A new class of rigid low-molecular-mass organic gelators (LMOGs) was synthesized by McMurry and Heck reactions, and their gels and photophysical properties were investigated. The LMOGs lacked alkyl chain and H-bonding units and produced good gelation ability in selected mixed organic solvents facilitated by cooperative π–π stacking and C═O···π interactions. Sensitive gel–sol transformation by molecular aggregation and disaggregation was easily achieved upon heating and cooling. H–H 2D NOESY and X-ray diffraction (XRD) patterns showed the π–π stacking and C═O···π interactions between tiny methyl acrylate groups as “tails”. Importantly, this soft interaction model offers a useful tool for the future design and construction of supramolecular structures. At present, the LMOGs reported herein offer a sensitive gel-formation ability and aggregation-induced emission (AIE) property and thus have promising application potentials as functional soft matter in amorphous materials, photoelectric materials, and so on.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu and Ziqiang Lei
Journal of Materials Chemistry A 2014 vol. 2(Issue 41) pp:17297-17301
Publication Date(Web):02 Sep 2014
DOI:10.1039/C4TA03929G
A facile one-step activation and nitrogen-doping combination method is developed for preparation of nitrogen-doped graphene-like carbon nanosheets (N-CNSs). The N-CNSs have abundant wrinkled structures and ultrahigh pore volume (3.19 cm3 g−1), and are used as high-performance electrode materials for supercapacitors.
Co-reporter:Hui Peng, Guofu Ma, Jingjing Mu, Kanjun Sun and Ziqiang Lei
Journal of Materials Chemistry A 2014 vol. 2(Issue 27) pp:10384-10388
Publication Date(Web):08 May 2014
DOI:10.1039/C4TA01899K
Asymmetric supercapacitors (ASCs) with high energy density are assembled based on the pseudocapacitance of both electrodes, which use polyaniline (PANI) nanotubes as positive electrodes and MoO3 nanobelts as negative electrodes in a 1 M H2SO4 aqueous electrolyte. The assembled novel PANI//MoO3 ASC device with an extended operating voltage window of 2.0 V, in spite of the use of an aqueous electrolyte, exhibits excellent performance such as a high specific capacitance of 518 F g−1 at a current density of 0.5 A g−1, reaching an energy density as high as 71.9 W h kg−1 at a power density of 254 W kg−1 and good cycling stability.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu, Hui Wang and Ziqiang Lei
Journal of Materials Chemistry A 2014 vol. 2(Issue 10) pp:3303-3307
Publication Date(Web):02 Dec 2013
DOI:10.1039/C3TA13859C
We have developed a supercapacitor electrode composed of CuS microspheres with polypyrrole (PPy) uniformly inserted into the sheet-like subunit structure and coated onto the CuS surface to enhance the pseudocapacitive performance. Novel sphere-like CuS particles with intertwined sheet-like subunit structure are fabricated by a solvothermal approach without any surfactant or template. A CuS@PPy composite electrode is prepared by in situ oxidation polymerization of pyrrole in the presence of the CuS suspension. The CuS@PPy composite (CuS content is 16.7 wt%) exhibits a high specific capacitance of 427 F g−1 (at 1 A g−1) and its capacitance can still retain 88% after 1000 cycles.
Co-reporter:Jian Li, Zhijiao Jing, Fei Zha, Yaoxia Yang, Qingtao Wang, and Ziqiang Lei
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 11) pp:8868
Publication Date(Web):May 8, 2014
DOI:10.1021/am5015937
In this paper, tunable adhesive superhydrophobic ZnO surfaces have been fabricated successfully by spraying ZnO nanoparticle (NP) suspensions onto desired substrates. We regulate the spray-coating process by changing the mass percentage of hydrophobic ZnO NPs (which were achieved by modifying hydrophilic ZnO NPs with stearic acid) in the hydrophobic/hydrophilic ZnO NP mixtures to control heterogeneous chemical composition of the ZnO surfaces. Thus, the water adhesion on the same superhydrophobic ZnO surface could be effectively tuned by controlling the surface chemical composition without altering the surface morphology. Compared with the conventional tunable adhesive superhydrophobic surfaces, on which there were only three different water sliding angle values: lower than 10°, 90° (the water droplet is firmly pinned on the surface at any tilted angles), and the value between the two ones, the water adhesion on the superhydrophobic ZnO surfaces has been tuned effectively, on which the sliding angle is controlled from 2 ± 1° to 9 ± 1°, 21 ± 2°, 39 ± 3°, and 90°. Accordingly, the adhesive force can be adjusted from extremely low (∼2.5 μN) to very high (∼111.6 μN). On the basis of the different adhesive forces of the tunable adhesive superhydrophobic surfaces, the selective transportation of microdroplets with different volumes was achieved, which has never been reported before. In addition, we demonstrated a proof of selective transportation of microdroplets with different volumes for application in the droplet-based microreactors via our tunable adhesive superhydrophobic surfaces for the quantitative detection of AgNO3 and NaOH. The results reported herein realize the selective transportation of microdroplets with different volumes and we believe that this method would potentially be used in many important applications, such as selective water droplet transportation, biomolecular quantitative detection and droplet-based biodetection.Keywords: heterogeneous chemistry; selective transportation; spray-coating; superhydrophobic surfaces; tunable adhesion;
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu, Zhe Zhang, and Ziqiang Lei
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 23) pp:20795
Publication Date(Web):November 5, 2014
DOI:10.1021/am505066v
Two-dimensional mesoporous carbon nanosheets (CNSs) have been prepared via simultaneous activation and catalytic carbonization route using macroporous anion-exchange resin (AER) as carbon precursor and ZnCl2 and FeCl3 as activating agent and catalyst, respectively. The iron catalyst in the skeleton of the AER may lead to carburization to form a sheetlike structure during the carbonization process. The obtained CNSs have a large number of mesopores, a maximum specific surface area of 1764.9 m2 g–1, and large pore volume of 1.38 cm3 g–1. As an electrode material for supercapacitors application, the CNSs electrode possesses a large specific capacitance of 283 F g–1 at 0.5 A g–1 and excellent rate capability (64% retention ratio even at 50 A g–1) in 6 mol L–1 KOH. Furthermore, CNSs symmetric supercapacitor exhibits specific energies of 17.2 W h kg–1 at a power density of 224 W kg–1 operated in the voltage range of 0–1.8 V in 0.5 mol L–1 Na2SO4 aqueous electrolyte, and outstanding cyclability (retains about 96% initial capacitance after 5000 cycles).Keywords: activation; anion-exchange resin; carbon nanosheets; catalytic carbonization; supercapacitors
Co-reporter:Guofu Ma, Jiajia Li, Kanjun Sun, Hui Peng, Jingjing Mu, Ziqiang Lei
Journal of Power Sources 2014 Volume 256() pp:281-287
Publication Date(Web):15 June 2014
DOI:10.1016/j.jpowsour.2014.01.062
•Alkali and potassium ferricyanide doped polyvinyl alcohol gel electrolyte is prepared.•The PVA–KOH–K3[Fe(CN)6] gel electrolyte can also be used as separator.•The introduction of K3[Fe(CN)6] increases the ionic conductivity of electrolyte.•The supercapacitor exhibits flexible and wide potential window properties.A gel polymer PVA–KOH–K3[Fe(CN)6] is prepared by potassium hydroxide and potassium ferricyanide doped polyvinyl alcohol, and a solid-state supercapacitor is assembled using the gel polymer as electrolyte and separator, activated carbons as electrode. The gel polymer exhibits flexible, high ionic conductivity and wide potential properties. The electrochemical properties of the supercapacitor are investigated using cyclic voltammetry, galvanostatic charge/discharge, and impedance spectroscopy techniques. The electrode specific capacitance of the supercapacitor can be as high as 430.95 F g−1, and after 1000 cycles at a current density of 1 A g−1 it still remains higher than 380 F g−1. The energy density and power density of the supercapacitor reach 57.94 Wh kg−1 and 59.84 kW kg−1, respectively. These novel flexible gel polymers are desirable for applications in supercapacitor devices.
Co-reporter:Guofu Ma, Enke Feng, Kanjun Sun, Hui Peng, Jiajia Li, Ziqiang Lei
Electrochimica Acta 2014 Volume 135() pp:461-466
Publication Date(Web):20 July 2014
DOI:10.1016/j.electacta.2014.05.045
•Alkali and P-phenylenediamine doped polyvinyl alcohol gel electrolyte is prepared.•The PVA-KOH-PPD gel electrolyte can also be used as separator.•The introduction of PPD increases the ionic conductivity of electrolyte.•The supercapacitor exhibits flexible and high energy density.A supercapacitor utilize a novel redox-mediated gel polymer (PVA-KOH-PPD) as electrolyte and separator, and activated carbon as electrodes is assembled. The PVA-KOH-PPD gel polymer as potential electrolyte for supercapacitor is investigated by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy techniques. It is found that the supercapacitor exhibits high ionic conductivity (25 mS cm−1), large electrode specific capacitance (611 F g−1) and high energy density (82.56 Wh kg−1). The high performance is attributed to the addition of quick redox reactions at the electrolyte|electrode interface as PPD undergoes a two-proton/two-electron reduction and oxidation during cycling. Furthermore, the supercapacitor with PVA-KOH-PPD gel polymer shows excellent charge-discharge stability, after 1000 charge-discharge cycles, the supercapacitor still retains a high electrode specific capacitance of 470 F g−1. It is believed that the idea using redox mediator has a good prospect for improving the performances of supercapacitors.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu, Mengting Luo, Ziqiang Lei
Electrochimica Acta 2014 Volume 147() pp:54-61
Publication Date(Web):20 November 2014
DOI:10.1016/j.electacta.2014.09.100
The demand for high-performance energy storage devices such as supercapacitors and lithium-ion batteries has been increasing to meet the application requirements of renewable energy systems. Here, high energy density aqueous asymmetric supercapacitor (ASC) is assembled based on carbon nanofibers (CNF) network positive electrode and tungsten trioxide (WO3) nanorod bundles negative electrode. Polyaniline-based CNF are prepared by direct carbonization of polyaniline nanofibers. WO3 nanorod bundles are synthesized via a simple sodium chloride assisted hydrothermal process. The CNF//WO3 ASC device operates with a voltage of 1.6 V and achieved a high energy density of 35.3 Wh kg−1 at a power density of 314 W kg−1. Furthermore, the device shows an excellent cycling performance with capacitance retention of 88% after 1000 cycles.
Co-reporter:Enke Feng, Guofu Ma, Yajuan Wu, Haiping Wang, Ziqiang Lei
Carbohydrate Polymers 2014 Volume 111() pp:463-468
Publication Date(Web):13 October 2014
DOI:10.1016/j.carbpol.2014.04.031
•Novel organic–inorganic composite superabsorbent was successfully synthesized.•Low-cost, abundant reserves and eco-friendly loess is used as raw material.•The composite superabsorbent exhibits excellent swelling ratio and pH stability.•These excellent properties are attributed to organic–inorganic crosslinking polymerization.A new, low-cost, and eco-friendly organic–inorganic composite superabsorbent was successfully synthesized in aqueous solution by polymerization xanthan gum (XG), neutralized acrylic acid (AA) and loess using ammonium persulfate (APS) as initiator and N,N-methylenebisacrylamide (MBA) as crosslinker. Structure and morphological characterizations of the composite superabsorbent were investigated by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The loess content, pH values, surfactants, salts and temperature which could affect the swelling and water-retention capabilities of the composite superabsorbent were investigated. The composite superabsorbent exhibits excellent water absorbency (610 g/g in distilled water), pH-stability (pH 5–10), and higher swelling capacity in anionic surfactant solution; on the other hand, the composite superabsorbent can be used for removing multivalent metal ions.
Co-reporter:Qingtao Wang, Ruirong Li, Dong Yu, Xiaozhong Zhou, Jian Li and Ziqiang Lei
RSC Advances 2014 vol. 4(Issue 96) pp:54134-54139
Publication Date(Web):30 Sep 2014
DOI:10.1039/C4RA07674E
The application of a silicon-based Li-ion battery anode is limited by the poor cycling stability associated with its large volume changes during the charging and discharging processes. Herein, we report a facile solution process to fabricate silicon composite anodes by encapsulating Si nanoparticles with in situ polymerized aniline and pyrrole copolymers. The copolymer matrix can accommodate the considerable volume changes of Si during the cycling process. Therefore, the as-prepared Si/poly(aniline-co-pyrrole) composite electrodes successfully achieve higher capacity and better cycling performance than the bare nano-Si anode. The specific capacity of the composite electrode retains 637 mA h g−1 after 50 cycles.
Co-reporter:Li Wenfeng, Ma Hengchang and Lei Ziqiang
RSC Advances 2014 vol. 4(Issue 74) pp:39351-39358
Publication Date(Web):13 Aug 2014
DOI:10.1039/C4RA05843G
Detection of explosives is of utmost importance due to the threat to human security as a result of illegal transport and terrorist activities. Picric acid (PA) is widely used in the industrial and military fields, and is inadvertently able to contaminate the environment and groundwater, posing a threat to human health. Achieving the detection of explosives at the parts per billion (ppb) level using chemosensors is a great challenge. Herein, we demonstrate that triphenylamine based fluorescent chemosensors tris(4′-carbethoxybiphenyl) amine (TCEPA) and tris(4′-carboxybiphenyl) amine (TCPA) exhibit superior detection capability for PA in solution state at the ppb level (40 ppb and 5 ppb respectively) and efficient quenching behaviours in the vapor phase at room temperature. In addition, fluorescent test strips have been prepared by dip-coating Thin Layer Chromatography (TCL) for trace detection of PA at the attogram level.
Co-reporter:Hengchang Ma;Feng Wang;Wenfeng Li;Yuan Ma;Xiaoqiang Yao;Dedai Lu;Yaoxia Yang;Zhe Zhang
Journal of Physical Organic Chemistry 2014 Volume 27( Issue 9) pp:722-728
Publication Date(Web):
DOI:10.1002/poc.3331
Click chemistry is employed to couple two β-cyclodextrins at both ends of azobenzene moiety yielding dumbbell-shaped amphiphiles (AZO-β-CD dimer) constructed by rigid aromatic building blocks as “body”, and hydrophilic cyclodextrins as “head” with almost quantitative yield and purity. Bulk aggregates formed by the self-assembly of the supraamphiphiles through π–π stacking and hydrophobic effect are observed. Meanwhile, the rationally designed polyesters, named as AZO-PCL with controllable molecular weights and low polydispersities, are successfully synthesized by ring-opening polymerization of ε-caprolactone in the presence of p-aminoazobenzene as initiator. In the aqueous phase, very stable spherical particles are formed by host–guest interactions between AZO-β-CD and AZO-PCLs; the spherical aggregates inherit the photo-responsiveness of azobenzene. The detailed aggregation and disaggregation behaviors are fully investigated by TEM, SEM, NMR, 2D NOESY, IR, UV and XRD measurements. Compared to the previous works, our newly developed system can be fabricated with more readily manners, avoiding tedious synthetic process; the reversible and dynamic nature of the non-covalent interactions also can be modulated alternatively by UV or visible light. Thus, such dumbbell-shaped supra-amphiphiles are of great potential applications in the controlled delivery systems. Copyright © 2014 John Wiley & Sons, Ltd.
Co-reporter:Dedai Lu;Pengxue Duan;Tao Liu;Juan Li;Ting'e Li
Polymer International 2014 Volume 63( Issue 2) pp:244-251
Publication Date(Web):
DOI:10.1002/pi.4494
Abstract
A series of biodegradable linear–hyperbranched barbell-like poly(ethylene glycol) (PEG)-supported poly(lactic-ran-glycolic acid) (PLGA) copolymers were synthesized with PEG, d,l-lactic acid aqueous solution, glycolic acid and gluconic acid (Glu) under bulk conditions. The branching density of the hyperbranched section was varied by controlling the molar ratio of Glu to hydroxyl-terminal groups of PEG ([Glu]/[OH] = 1, 3.5, 6.0, 8.5). Chemical structures of these copolymers were confirmed using NMR spectroscopy. The molecular weights were determined using 1H NMR group analysis and gel permeation chromatography, both results being consistent with one another. The results of hydrolytic degradation indicate that these copolymers can degrade completely in no more than three weeks. The thermal properties were evaluated using differential scanning calorimetry and thermogravimetric analysis. The results indicate that the glass transition temperatures and melt temperatures of these copolymers are not above 50 °C. The self-assembly behavior of the copolymers on hydrophilic surfaces was also investigated. The morphology of self-assembly films made of the copolymers was observed using atomic force microscopy, and the results indicate that these copolymers exhibit more inhomogeneous and rough structural orientated films on a silicon wafer substrate with increasing branching densities. Due to the favorable biodegradability and biocompatibility of the PLGA and PEG, the results suggest new possibilities for these novel structural amphiphilic linear–hyperbranched barbell-like copolymers as potential biomaterials. © 2013 Society of Chemical Industry
Co-reporter:Jinhui Tong;Haiyan Wang;Xiaodong Cai;Qianping Zhang;Hengchang Ma
Applied Organometallic Chemistry 2014 Volume 28( Issue 2) pp:95-100
Publication Date(Web):
DOI:10.1002/aoc.3086
A hybrid compound consisting of palladium(salen) [salen = N,N′-bis(salicylidene)ethylenediamine] complex covalently linked to a lacunary Keggin-type polyoxometalate, K8[SiW11O39](POM), was synthesized and characterized by FT-IR, elemental analysis, inductively coupled plasma and diffuse reflectance UV–visible spectroscopic methods. The hybrid, [Pd(salen)–POM], was investigated in the Suzuki cross-coupling in EtOH/H2O under mild reaction conditions. In comparison to the corresponding organic and inorganic moiety, the hybrid has shown greatly improved catalytic activity, and much higher yields toward coupling products were obtained with a low catalyst loading for various aryl halides, including unreactive and sterically hindered ones. The catalyst also exhibited prominent recyclable performance and no obvious loss of activity was observed after six consecutive runs. Copyright © 2013 John Wiley & Sons, Ltd.
Co-reporter:Guofu Ma, Yajuan Wu, Kanjun Sun, Hui Peng, Haiping Wang, Ziqiang Lei
Materials Letters 2014 Volume 132() pp:41-44
Publication Date(Web):1 October 2014
DOI:10.1016/j.matlet.2014.06.028
•Polyaspartic acid was used to prepare nitrogen-doped porous carbon.•The morphologies and structures of carbon deeply depend on carbonization temperature.•Carbon exhibits high specific capacitance and excellent cycling stability.•The approach may be used in all amino acids to prepare nitrogen-doped carbon.Nitrogen-doped porous carbon is prepared by carbonizing polyaspartic acid under inertia atmosphere without template and activation. The powder X-ray diffraction, element analysis, scanning electron microscopy, and N2 adsorption–desorption tests show that the morphologies and structures of the nitrogen-doped carbon samples deeply depend on carbonization temperature. Electrochemical measurements show that the specific capacitance of the PASP700 sample obtained at 700 °C is 166.1 F g−1 at a current density of 1 A g−1, and after 5000 charge/discharge cycles it still remains 97% which exhibits an excellent cycling stability.
Co-reporter:Hui Peng, Guofu Ma, Jingjing Mu, Kanjun Sun, Ziqiang Lei
Materials Letters 2014 Volume 122() pp:25-28
Publication Date(Web):1 May 2014
DOI:10.1016/j.matlet.2014.01.173
•CuS with different morphologies are prepared via solvothermal methods in different solvents.•CuS electrode materials have a wide electrochemical window (1.5 V) in an aqueous electrolyte.•The flower-like CuS exhibit high specific capacitance and excellent cycling stability.•These excellent electrochemical properties of CuS are attributed to the special architecture.CuS with different morphologies (plate-like, nanoparticle-like, sphere-like, and flower-like) are successfully synthesized via a simple low-temperature solvothermal approach without any surfactant or template. CuS are used as supercapacitor electrode materials, which provide a large voltage window as high as 1.5 V and excellent capacitive performance in an aqueous electrolyte. The specific capacitance of the flower-like CuS synthesized in glycerol can reach up to 597 F g−1 (at 1 A g−1). Meanwhile, the flower-like CuS exhibits a good cycling stability.
Co-reporter:Hengchang Ma;Yuan Ma;Wenfeng Li;Feng Wang;Fuping Zhu;Chunxuan Qi;Zhongwei Zhang;Xiaoqiang Yao
Macromolecular Chemistry and Physics 2014 Volume 215( Issue 23) pp:2305-2310
Publication Date(Web):
DOI:10.1002/macp.201400357
Co-reporter:Xiaodong Cai, Haiyan Wang, Qianping Zhang, Jinhui Tong, Ziqiang Lei
Journal of Molecular Catalysis A: Chemical 2014 Volumes 383–384() pp:217-224
Publication Date(Web):March 2014
DOI:10.1016/j.molcata.2013.12.007
•The catalyst has been proved much more efficient for cyclohexene oxidation.•The preparation method is simple and economical.•The catalyst can be easily separated by external magnetic field and has exhibited excellent reusability.•The catalytic system is environmentally friendly.Five magnetic core–shell type Fe3O4@chitosan-Schiff base Co(II), Cu(II) and Mn(II) complexes were prepared in a simple way and well characterized by Fourier transform infrared spectrophotometry (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS) and thermogravimetry (TG). Their abilities to catalyze oxidation of cyclohexene with molecular oxygen in the absence of any solvents or reducing agents were investigated. It has been revealed that the as-prepared samples have high catalytic activities for heterogeneously aerobic oxidation of cyclohexene and 2-cyclohexene-1-one is the main product in all cases. Especially, when the Schiff base Co(II) complex derived from 5-nitrosalicyaldehyde was employed as catalyst, 46.8% of cyclohexene conversion, 77.2% of selectivity for 2-cyclohexene-1-one and as high as 4.7 × 103 of turnover number were obtained under ambient pressure at 70 °C for 12 h of reaction. The catalyst can be magnetically separated easily for reuse and no obvious loss of activity was observed when reused in five consecutive runs.Five magnetic core–shell type Fe3O4@chitosan-Schiff base Co(II), Cu(II) and Mn(II) complexes were prepared in a simple way. Their abilities to catalyze oxidation of cyclohexene with molecular oxygen in the absence of any solvents or reducing agents were investigated. It has been revealed that the as-prepared samples have high catalytic activities for heterogeneously aerobic oxidation of cyclohexene and 2-cyclohexene-1-one is the main product in all cases. Especially, when the Schiff base Co(II) complex derived from 5-nitrosalicyaldehyde was employed as catalyst, 46.8% of cyclohexene conversion, 77.2% of selectivity for 2-cyclohexene-1-one and as high as 4.7 × 103 of turnover number were obtained under ambient pressure at 70 °C for 12 h of reaction. The catalyst can be magnetically separated easily for reuse and no obvious loss of activity was observed when reused in five consecutive runs.
Co-reporter:Hui Peng ; Guofu Ma ; Kanjun Sun ; Jingjing Mu ; Zhe Zhang
The Journal of Physical Chemistry C 2014 Volume 118(Issue 51) pp:29507-29516
Publication Date(Web):November 25, 2014
DOI:10.1021/jp508684t
We introduce a facile integrated oxidation polymerization and catalytic carbonization method to prepare three-dimensional porous nitrogen-doped carbon networks (3D N-CNWs) with high nitrogen content (about 8.4 wt %) directly from poly(p-phenylenediamine). In the synthesis process, the FeCl3 serves not only as an oxidant for oxidative polymerization of p-phenylenediamine monomers but also as the carbonization catalyst to promote porous carbon network formation. The 3D N-CNWs prepared at 700 °C exhibit an interconnected porous framework with high specific surface area and show remarkable performance as an electrode material for supercapacitors. The maximum specific capacitance of 304 F g–1 at a current density of 0.5 A g–1, which retains the high values of 226 F g–1 even at a high current density of 20 A g–1, is obtained for the N-CNW electrode in 6 M KOH aqueous solution. Moreover, the as-assembled N-CNW symmetric supercapacitor exhibits a considerably high energy density of 15.8 Wh kg–1 at a power density of 450 W kg–1 operated in the voltage range 0–1.8 V in 0.5 M Na2SO4 aqueous solution, and exhibits an excellent cycling performance with 97% specific capacitance retention after 5000 cycles.
Co-reporter:Jian Li, Jing Ling, Long Yan, Qingtao Wang, Fei Zha, Ziqiang Lei
Surface and Coatings Technology 2014 Volume 258() pp:142-145
Publication Date(Web):15 November 2014
DOI:10.1016/j.surfcoat.2014.09.040
•Superhydrophobic CNT surfaces were fabricated by a facile spray-coating process.•Switchable transition between the low and high adhesive state can be realized.•The switching on–off water transportation was achieved based on the superhydrophobic surfaces with switchable water adhesion.We used a simple spray-coating process to prepare superhydrophobic carbon nanotube (CNT) surfaces with a water contact angle (CA) of 160° and a sliding angle (SA) of 3° on desired substrates without any chemical modification. After being irradiated by UV light through a photomask, the as-prepared low adhesive superhydrophobic CNT surface changes to high water adhesion. However, further heating the irradiated CNT surface, the irradiated CNT surface becomes its original low water adhesion again. Reversibly switchable transition between the low water adhesion and high water adhesion can be realized simply by UV/mask illumination and heat treatment alternately. Simultaneously, the adhesive force of the superhydrophobic CNT surfaces changes from low (~ 8.9 μN) to very high (~ 133.6 μN). Based on the reversible water adhesion transition on the superhydrophobic CNT surfaces through UV illumination and heat treatment alternately, switching on–off water transportation was achieved. This switchable water adhesion on the superhydrophobic CNT surfaces could have potential applications in areas requiring multifunctional CNT-based surfaces.Switchable transition between the low and high adhesion on the superhydrophobic CNT surfaces can be realized simply by UV illumination and heat alternately. Based on the reversible water adhesion transition on the surfaces, switching on–off water transportation was achieved.
Co-reporter:Guofu Ma, Hui Peng, Jingjing Mu, Haohao Huang, Xiaozhong Zhou, Ziqiang Lei
Journal of Power Sources 2013 Volume 229() pp:72-78
Publication Date(Web):1 May 2013
DOI:10.1016/j.jpowsour.2012.11.088
We report a facile strategy to synthesize of polypyrrole/molybdenum disulfide (PPy/MoS2) nanocomposite as an advanced electrode material for high-performance supercapacitors applications. Flowerlike MoS2 with graphene-like subunits structure is prepared using a hydrothermal method, and the nanocomposite PPy are embedded in MoS2 nanosheets is prepared by in situ oxidation polymerization of pyrrole in the presence of MoS2 suspension. Structural and morphological characterizations of the nanocomposite are investigated by XRD, FE-SEM and TEM measurements. Their electrochemical properties are also investigated using cyclic voltammetry, and galvanostatic charge/discharge. The PPy/MoS2 nanocomposite exhibit high specific capacitance of 553.7 F g−1 and its capacitance can still remain 90% after 500 cycles at a current density of 1 A g−1.Graphical abstractHighlights► Flowerlike MoS2 with graphene-like structure is prepared by hydrothermal method. ► The PPy/MoS2 nanocomposite is prepared by in situ oxidation polymerization. ► The MoS2 provides a path for insertion and extraction of ions within PPy. ► This PPy/MoS2 nanocomposite exhibit high capacity and excellent cycling stability.
Co-reporter:Peng Fei, Ming Zhong, Ziqiang Lei, Bitao Su
Materials Letters 2013 Volume 108() pp:72-74
Publication Date(Web):1 October 2013
DOI:10.1016/j.matlet.2013.06.098
•New enhanced magnetic ZF–rGO composite was prepared by one-pot solvothermal method.•Ethylene glycol played dual function as solvent and reducing agent for GO and Fe3+.•A high-effective adsorption property for MB removal.•Easy and effective magnetic separation property.Zinc ferrite–reduced graphene oxide (ZF–rGO) magnetic adsorbent was prepared by a facile one-pot solvothermal method. TEM study suggests that zinc ferrite (ZF) nanoparticle is uniformly distributed and firmly anchored on the reduced graphene oxide (rGO) with a high density. The magnetic and adsorptive experiments' results demonstrate that both of the ZF and ZF–rGO show enhanced magnetic properties and the ZF–rGO composite material is an ideal adsorbent candidate for removing methylene blue (MB) in water due to its high adsorption capacity and easy and effective separable property based on its outstanding magnetic property. The adsorption behavior follows a pseudo-second-order kinetic model.
Co-reporter:Hui Peng, Guofu Ma, Wenmei Ying, Aidi Wang, Haohao Huang, Ziqiang Lei
Journal of Power Sources 2012 Volume 211() pp:40-45
Publication Date(Web):1 August 2012
DOI:10.1016/j.jpowsour.2012.03.074
Polyaniline/sodium carboxymethyl cellulose (PANI/CMC) nanorods have been synthesized via in-situ oxidation polymerization of aniline in the presence of sodium carboxymethyl cellulose as a polymerization template. The structure and morphology of the nanorods are characterized by TEM, FE-SEM and XRD. The size and shape of the composite nanorods are uniform with a diameter of 100 nm. Their electrochemical properties are also investigated using cyclic voltammetry and galvanostatic charge/discharge measurement. The specific capacitance of PANI/CMC nanorods prepared with 20 wt% CMC can be as high as 451.25 F g−1. Its capacitance remains higher than 300 F g−1 after 1000 cycles at a current density of 1 A g−1. These novel nanorods are desirable for applications in supercapacitor devides.Graphical abstractHighlights► Sodium carboxymethyl cellulose is employed as a polymerization oriented agent. ► Uniform diameters about 100 nm polyaniline/sodium carboxymethyl cellulose nanorods are obtained by a facile method. ► This novel nanorods for supercapacitors showed enhanced specific capacitance and cycling stability than pure polyaniline.
Co-reporter:Jian Li, Yaoxia Yang, Fei Zha, Ziqiang Lei
Materials Letters 2012 Volume 75() pp:71-73
Publication Date(Web):15 May 2012
DOI:10.1016/j.matlet.2012.01.139
Superhydrophobic surface is commonly fabricated by a combination of micro- and nano-scale structure and low surface energy materials. In this paper, superhydrophobic ZnO surfaces with controllable water adhesion have been fabricated by combining both a simple hydrothermal process and self-assembly of stearic acid. We regulate the hydrothermal process by using different zinc salt aqueous solution to control different morphologies of ZnO surfaces. After being modified with stearic acid, the as-prepared ZnO surfaces show an analogous extreme nonwetting property but high contrast water adhesion that ranges from very high to extremely low. This simple and practical method can provide an important strategy for the adhesion adjustment on superhydrophobic surfaces.Graphical► Superhydrophobic ZnO surfaces were fabricated by a simple hydrothermal method. ► The water adhesion on the surfaces was controlled from very high to extremely low. ► A droplet can be transferred from the low adhesive to the high adhesive ZnO surface.
Co-reporter:Guofu Ma;Zhenhong Ma;Zhifang Zhang;Zhiwang Yang
Journal of Porous Materials 2012 Volume 19( Issue 5) pp:597-604
Publication Date(Web):2012 October
DOI:10.1007/s10934-011-9510-9
Aluminium chloride supported by tubular alumina, which was treated by absorbent cotton as a template, was prepared via chemical tailoring method. Scanning electron microscopy, transmission electron microscopy, N2 adsorption techniques and X-ray diffraction characterization showed alumina well replicated the nanoporous morphologies and hierarchical pore size of original cotton, and via chemical tailoring method, the active component aluminium chloride distributed evenly on the surface of the support. Using different concentration of hydrochloric acid, the morphology, structure and component of tubular alumina supported aluminium chloride could be controllably synthesized. The Baeyer–Villiger oxidation reactions of ketones catalyzed by the supported aluminium chloride, with 30% hydrogen peroxide as an oxidant, were carried out. The experimental results revealed that this type of reactions could proceed in ethanol at 70 °C with good yield (96%) and high regioselectivity (99%), exemplified by transforming of 2-adamantanone. The tubular alumina supported aluminium chloride could be reused several times without significant losses of their catalytic activity and selectivity.
Co-reporter:Hengchang Ma, Wenfeng Li, Jian Wang, Guanghai Xiao, Yuan Gong, Chunxuan Qi, Yunpeng Feng, Xiufang Li, Zhikang Bao, Wei Cao, Qiangsheng Sun, Caraus Veaceslav, Feng Wang, Ziqiang Lei
Tetrahedron 2012 68(39) pp: 8358-8366
Publication Date(Web):
DOI:10.1016/j.tet.2012.07.012
Co-reporter:Hui Wang, Xiangtai Zhang, Rongfang Wang, Shan Ji, Wei Wang, Qizhao Wang, Ziqiang Lei
Journal of Power Sources 2011 Volume 196(Issue 19) pp:8000-8003
Publication Date(Web):1 October 2011
DOI:10.1016/j.jpowsour.2011.05.062
This study examines the electro-catalytic behaviour of Pt decorating amorphous alloys in the electro-oxidation of ethanol. Pt decorated CoSn nanoparticles on carbon (denoted as Pt-CoSn/C) are prepared using a two-stage chemical synthesis (sol–gel preparation and Steady-state replacement method). The structure of Pt-CoSn/C nanoparticles is confirmed by the transmission electron microscopy (TEM) and X-ray diffraction (XRD). Under the same quantity of platinum, the Pt-CoSn/C nanoparticles have higher activity in alcohol oxidation than the Pt/C, PtRu/C and PtSn/C nanoparticles in cyclic voltammetry tests. The structure of Pt decorating amorphous CoSn alloys notably decreases the usage of Pt and enhances its catalytic activity at the same time.Highlights► Pt decorating CoSn amorphous alloys were prepared as an effective and low-cost electrocatalysts for ethanol oxidation. ► The structure of Pt decorated amorphous CoSn alloys could obviously decrease the usage of Pt and enhance its catalytic activity at the same time. ► Amorphous CoSn alloy was decorated by Pt as the catalyst was confirmed to be one of the promising best choices for alcohols oxidation.
Co-reporter:Yun-Mei Zhong, Heng-Chang Ma, Jin-Xia Wang, Xiao-Jie Jia, Wen-Feng Li and Zi-Qiang Lei
Catalysis Science & Technology 2011 vol. 1(Issue 6) pp:927-931
Publication Date(Web):22 Jun 2011
DOI:10.1039/C1CY00165E
AlBr3·6H2O was found to be an efficient catalyst in the field of oxidation of benzylic alcohols. Primary and secondary benzylic alcohols could be transformed into corresponding aldehydes and ketones with almost complete conversion and high selectivity. The non-transition metal related reaction systems have an incomparable advantage over others, such as easy work-up, excellent selectivity as well as commercial availability.
Co-reporter:Rongfang Wang, Jingchun Jia, Hao Li, Xusheng Li, Hui Wang, Yanming Chang, Jian Kang, Ziqiang Lei
Electrochimica Acta 2011 Volume 56(Issue 12) pp:4526-4531
Publication Date(Web):30 April 2011
DOI:10.1016/j.electacta.2011.02.066
An electrocatalyst support, nitrogen-doped graphitic layer (CNx) coated palygorskite (PLS) (donated as PLS@CNx), is synthesized by carbonizing the polypyrrole (PPy) coated PLS and is explored for the first time as a cathode electrocatalyst support in proton exchange membrane fuel cell. The structural and chemical properties of the PLS@CNx are investigated by Fourier-Transform infrared spectrometer, thermogravimetric analysis, X-ray diffraction and transmission electron microscopy. The electrocatalytic activity and stability of Pt/PLS@CNx toward oxygen reduction reaction (ORR) are studied by cyclic voltammetry (CV) and steady state polarization measurements. Upon loading Pt (20 wt%), the catalysts exhibit superior catalytic performance during ORR, surpassing the conventional Pt/C (Vulcan XC-72) catalysts. High electrocatalytic activity and good stability can be attributed to the nitrogen atom incorporation and SiO2 component in PLS.Highlights► An electrocatalyst support, PLS@CNx composite nanoparticle, was fabricated by carbonizing polypyrrole-PLS hybridized precursor. ► Pt/PLS@CNx exhibited the higher activity and better stability than Pt/C for the oxygen reduction. ► High oxygen reduction electrocatalytic activity and good stability are attributed to the nitrogen atom incorporation and SiO2 component in PLS.
Co-reporter:Rongfang Wang, Xusheng Li, Hao Li, Qunfang Wang, Hui Wang, Wei Wang, Jian Kang, Yanming Chang, Ziqiang Lei
International Journal of Hydrogen Energy 2011 Volume 36(Issue 10) pp:5775-5781
Publication Date(Web):May 2011
DOI:10.1016/j.ijhydene.2010.12.132
We report a durable and active electrocatalyst, Pt/carbon nitride (CNx) modified silicon dioxide (SiO2) composite (donated as CNx/SiO2), for oxygen reduction reaction (ORR). CNx/SiO2 composite is synthesized by calcination of polypyrrole coated SiO2 (Ppy/SiO2) at 800 °C. The structure and composition are assessed using Fourier transform infra-red spectroscopy, X-ray diffraction, transmission electron microscope and energy dispersive spectroscopy. Voltammetry is used to study the activities of Pt immobilized on Vulcan XC-72R and CNx/SiO2, respectively. The electrochemical data indicate that Pt supported on CNx/SiO2 possesses higher electrocatalytic activity and durability for ORR compared with those of Vulcan XC-72R. All these demonstrate that CNx/SiO2 is a promising ORR electrocatalyst support for low temperature fuel cells.
Co-reporter:Hui Wang, Rongfang Wang, Hao Li, Qunfang Wang, Jian Kang, Ziqiang Lei
International Journal of Hydrogen Energy 2011 Volume 36(Issue 1) pp:839-848
Publication Date(Web):January 2011
DOI:10.1016/j.ijhydene.2010.09.033
One of the key objectives in fuel cell technology is to improve activity and reduce Pt loading of the electrocatalysts. In this work, carbon-supported pseudo-core@shell PdCu@Pt nanoparticles (donated as PdCu@Pt/C) with intimate contact of Pt and PdCu are prepared by a galvanic displacement reaction between PdCu/C alloy nanoparticles and PtCl62− in aqueous solution. The core@shell nanostructure is confirmed by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and cyclic voltammetry. The PdCu@Pt/C catalysts demonstrate enhanced specific activity to methanol oxidation and oxygen reduction. The present synthesis route is very facile and economical, which may be suitable for large-scale production of catalysts with low-cost and high activity.
Co-reporter:Hengchang Ma, Qiangsheng Sun, Wenfeng Li, Jinxia Wang, Zhe Zhang, Yaoxia Yang, Ziqiang Lei
Tetrahedron Letters 2011 Volume 52(Issue 14) pp:1569-1573
Publication Date(Web):6 April 2011
DOI:10.1016/j.tetlet.2011.01.056
Pd(acac)2 catalyzed dimerization of vinylarenes to form dimers under mild condition with excellent yields and stereoselectivities. In particular, the use of TFA highly promoted the activity and selectivity of the dimerization. The studies on mechanism for the reaction displayed clearly that the dimerization of styrenes is 100% atom economic reaction.
Co-reporter:Zhiwang Yang;Lengyuan Niu;Zhenhong Ma;Hengchang Ma
Transition Metal Chemistry 2011 Volume 36( Issue 3) pp:269-274
Publication Date(Web):2011 April
DOI:10.1007/s11243-011-9465-3
Catalytically active Sn/W mixed transition-metal oxides were prepared by calcination of the corresponding Sn/W hydroxide precursors at different temperatures. The obtained mixed oxides were characterized by physicochemical and spectroscopic methods. With variation of the molar ratios of Sn/W, the prepared Sn/W mixed oxide catalysts had different reaction activities. Thus, the Sn/W-2-800 oxide acted as an effective heterogeneous catalyst for the Baeyer–Villiger oxidation of ketones and the Friedel–Crafts reaction. Many ketones, as well as benzyl alcohol and acetic anhydride, were transformed into the corresponding products with high conversion and selectivity. The catalysts can be easily separated from the reaction mixtures and can be reused for at least five cycles without significant loss of activity.
Co-reporter:Shang Wu, Hengchang Ma, Xiaojie Jia, Yunmei Zhong, Ziqiang Lei
Tetrahedron 2011 67(1) pp: 250-256
Publication Date(Web):
DOI:10.1016/j.tet.2010.10.062
Co-reporter:Rongfang Wang;Bangxing Wei;Hui Wang;Shan Ji;Julian Key;Xiangtai Zhang
Ionics 2011 Volume 17( Issue 7) pp:
Publication Date(Web):2011 September
DOI:10.1007/s11581-011-0614-7
There is a growing interest in ethanol oxidation electrochemistry as it plays an important role in renewable energy technologies. The goal of this work was to develop active multifunctional catalyst materials for ethanol oxidation. Here, a carbon-supported Pt-modified IrCu alloy electrocatalyst (Pt–IrCu/C) was prepared by a two-step method. X-ray diffraction and transmission electron microscope showed that the Pt–IrCu/C has a two-phase structure: Pt nanoparticle-modified IrCu alloy. The Pt–IrCu/C catalyst was found to have not only a large electrochemically active specific area (SEAS) but also good CO oxidation ability for oxidation of ethanol compared to the commercial Pt/C electrocatalyst using cyclic voltammetry. Furthermore, the Pt current density of Pt–IrCu/C was more than 1.6 times as high as that of Pt/C for ethanol oxidation. The Pt–IrCu/C catalyst also exhibited more efficient usage of Pt and enhanced the stability of ethanol electro-oxidation compared with a Pt/C catalyst.
Co-reporter:Wei Wang, Rongfang Wang, Shan Ji, Hanqing Feng, Hui Wang, Ziqiang Lei
Journal of Power Sources 2010 Volume 195(Issue 11) pp:3498-3503
Publication Date(Web):1 June 2010
DOI:10.1016/j.jpowsour.2009.12.015
In this study, a novel core–shell structured Pd3Fe@Pt/C electrocatalyst, which is based on Pt deposited onto carbon supported Pd3Fe nanoparticles, is prepared for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). The carbon supported Pd3Fe nanoparticles act as seeds to guide the growth of Pt. The formation of the core–shell structured Pd3Fe@Pt/C is confirmed by transmission electron microscopy (TEM), X-ray diffraction (XRD) and electrochemical characterization. The higher surface area of the synthesized catalyst suggests that the utilization of Pt in the Pd3Fe@Pt/C catalyst is higher than that in Pt/C. Furthermore, better electrocatalytic performance than that of Pt/C and Pd3Fe/C catalyst is observed in the ORR which follows a four-electron path. Consequently, the results indicate that the Pd3Fe@Pt/C catalyst could be used as a more economically viable alternative for the ORR of PEMFCs.
Co-reporter:Rongfang Wang, Hao Li, Hanqing Feng, Hui Wang, Ziqiang Lei
Journal of Power Sources 2010 Volume 195(Issue 4) pp:1099-1102
Publication Date(Web):15 February 2010
DOI:10.1016/j.jpowsour.2009.08.055
In this study, a low-cost and high performance catalyst with core-shell structure of PdCu@PtRu/C for methanol oxidation is prepared by a two-step replacement reaction. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) examinations show that the composite catalyst particles distribution is quite homogeneous and has a high surface area. The Pt mass activity of this catalyst is about 15 and 3.4 times as large as those of the Pt/C and PtRu/C catalysts, respectively. High electrocatalytic activities could be attributed to the synergistic effect between PtRu and PdCu.
Co-reporter:Rongfang Wang, Hui Wang, Bangxing Wei, Wei Wang, Ziqiang Lei
International Journal of Hydrogen Energy 2010 Volume 35(Issue 19) pp:10081-10086
Publication Date(Web):October 2010
DOI:10.1016/j.ijhydene.2010.07.008
A catalyst for anode oxidation of methanol, carbon supported pseudo-core-shell PdCo@Pt particles with Pt shell is prepared via a two-step procedure, which consists of an organic colloid method and a surface replacement reaction step. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) are used for the catalysts characterization. The electrochemical surface areas (ECSA) are 6 and 4 times as large as those of Pt/C and PtRu/C catalysts, respectively. Furthermore, based on the Pt mass, the cyclic voltammetry (CV) and chronoamperometry results demonstrate that the electrocatalytic activity and stability of the PdCo@Pt/C catalyst for methanol oxidation are much higher than those of the Pt/C and PtRu/C catalysts. The PdCo@Pt/C catalyst is better utilization of Pt than pure Pt and Pt-based alloy catalysts.Figure options
Co-reporter:Shang Wu, Hengchang Ma, Ziqiang Lei
Tetrahedron 2010 66(45) pp: 8641-8647
Publication Date(Web):
DOI:10.1016/j.tet.2010.09.035
Co-reporter:Rongfang Wang, Zhe Zhang, Hui Wang, Ziqiang Lei
Electrochemistry Communications 2009 Volume 11(Issue 5) pp:1089-1091
Publication Date(Web):May 2009
DOI:10.1016/j.elecom.2009.03.026
In this study, a low-cost and high performance catalyst Pt decorating PdCu/C (Pt–PdCu/C) for methanol oxidation is prepared by a new two-stage route. TEM and XRD examinations show that the composite catalyst particles distribution is quite homogeneous and has a high surface areas. Catalytic activity and stability for the oxidation of methanol are studied by cyclic voltammetry and chronoamperometry. High electrocatalytic activities and good stabilities could be attributed to the synergistic effect between Pt and PdCu.
Co-reporter:De-Dai Lu;Jian-Chao Yuan ;Zi-Qiang Lei
Polymers for Advanced Technologies 2009 Volume 20( Issue 6) pp:536-540
Publication Date(Web):
DOI:10.1002/pat.1378
Abstract
High molecular weight poly(lactic acid-glycolic acid-ε-caprolactam) (PLGC) copolymer was synthesized by simply heating a mixture of DL-lactic acid aqueous, glycolic acid, and ε-caprolactam (CLM) using organic anhydride and tin (II) chloride dihydrate (SnCl2 · 2H2O) or metal powder as catalysts without organic solvents. At the same time, in order to investigate the effects of the structure of amino acid on the properties of copolymers, poly(lactic acid-glycolic acid-glycine) (PLGG), poly(lactic acid-glycolic acid-L-alanine) (PLGA-1), poly(lactic acid-glycolic acid-β-alanine). (PLGA-2), poly(lactic acid-glycolic acid-γ-aminobutyric acid) (PLGA-3), and poly(lactic acid-glycolic acid-L-phenylalanine) (PLGP) were synthesized under the same conditions, respectively. The structure of PLGC was confirmed by FT-IR and NMR spectra. The average molecular weight of PLGC was determined by the Ubbelohde model (corrected by 1H-NMR end-group analysis). The results indicated that compounds of organic anhydride and SnCl2 · 2H2O were active, and the highest average molecular weights could achieve 9800 Da. The thermal properties were evaluated using differential scanning calorimetry (DSC) and the results indicated that the glass transition temperatures (Tgs) of polyesteramide increased with the increase in the carbon atom numbers between carboxyl and amino-groups of amino acid. The Tgs were higher when α-carbon atom of amino acid linked with a “rigid” group than a “soft” group. The solubility and hydrolytic degradation of PLGC copolymers were investigated. Copyright © 2009 John Wiley & Sons, Ltd.
Co-reporter:Ziqiang Lei;Quanlu Yang;Shang Wu ;Xiaoli Song
Journal of Applied Polymer Science 2009 Volume 111( Issue 6) pp:3150-3162
Publication Date(Web):
DOI:10.1002/app.29360
Abstract
An organophilic palygorskite (o-PGS) prepared by the treatment of natural palygorskite with hexadecyl trimethyl ammonium bromide was incorporated into interpenetrating polymer networks (IPNs) of polyurethane (PU) and epoxy resin (EP), and a series of PU/EP/clay nanocomposites were obtained by a sequential polymeric technique and compression-molding method. X-ray diffraction and scanning electron microscopy analysis showed that adding nanosize o-PGS could promote the compatibility and phase structure of PU/EP IPN matrices. Tensile testing and thermal analysis proved that the mechanical and thermal properties of the PU/EP IPN nanocomposites were superior to those of the pure PU/EP IPN. This was attributed to the special fibrillar structure of palygorskite and the synergistic effect between o-PGS and the IPN matrices. In addition, the swelling behavior studies indicated that the crosslink density of PU/EP IPN gradually increased with increasing o-PGS content. The reason may be that o-PGS made the chains more rigid and dense. As for the flame retardancy, the PU/EP nanocomposites had a higher limiting oxygen index than the pure PU. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Co-reporter:Dedai Lu;Zongli Ren;Tianhong Zhou;Shoufeng Wang
Journal of Applied Polymer Science 2008 Volume 107( Issue 6) pp:3638-3643
Publication Date(Web):
DOI:10.1002/app.27549
Abstract
Poly(glutamic acid-co-lactic acid-co-glycolic acid) (PGLG), an amphiphilic biodegradable copolymer, was synthesized by simply heating a mixture of L-glutamic acid (Glu), DL-lactic acid, and glycolic acid with the present of stannous chloride. The unique branched architecture comprising of glutarimide unit, polyester unit, and polyamide unit was confirmed by NMR spectrum. The PGLG was soluble in many organic solvents and aqueous solution of sodium hydroxide (pH ≥ 9.0). The thermal properties were evaluated using thermogravimetric analysis and differential scanning calorimetry. Molecular weights were determined by 1H NMR end-group analysis and GPC, respectively, and the results indicated that the higher Glu content resulted in a decrease of the molecular weight. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Co-reporter:De Dai Lu;Jian Chao Yuan;Hongguang Li ;Zi-Qiang Lei
Journal of Polymer Science Part A: Polymer Chemistry 2008 Volume 46( Issue 11) pp:3802-3812
Publication Date(Web):
DOI:10.1002/pola.22729
Abstract
A series of multihydroxyl (2, 4, and 8) terminated poly(ethylene glycol)s and their biodegradable, biocompatible, and branched barbell-like (PLGA)n-b-PEG-b-(PLGA)n (n = 1, 2, 4) copolymers have been synthesized. The lengths of the PLGA arms were varied by controlling the molar ratio of monomers to hydroxyl groups of PEG ([LA+GA]0/[OH]0 = 23, 45, 90). Chemical structures of synthesized barbell-like copolymers were confirmed by both 1H and 13C-NMR spectroscopies. Molecular weights were determined by 1H-NMR end-group analysis and gel permeation chromatography. The result of hydrolytic degradation indicated that the rate of degradation increased with the increase of arm numbers or with the decrease of arm lengths. The thermal properties were evaluated by using differential scanning calorimetry and a thermogravimetric analysis. The results indicated that the thermal properties of barbell-like copolymers depended on the structural variations. The morphology of (PLGA)n-PEG-(PLGA)n copolymers self-assembly films were investigated by atomic force microscope, the results indicated that the microphase separation existed in (PLGA)n-PEG-(PLGA)n copolymers. Because of the favorable biodegradability and biocompatibility of the PLGA and PEG, these results may therefore create new possibilities for these novel structural amphiphilic barbell-like copolymers as potential biomaterials. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3802–3812, 2008
Co-reporter:Yanbin Bai;Ziqing Lei
Polymer International 2007 Volume 56(Issue 10) pp:
Publication Date(Web):21 MAR 2007
DOI:10.1002/pi.2269
Poly(lactic acid) was prepared by the utilization of the acid anhydrides cis-butenedoic anhydride, phthalic anhydride and pyromellitic dianhydride as catalysts. The effect of the amount of catalyst, temperature and reaction time on the polymerization was investigated in detail. The results show that the acid anhydride catalysts are very efficient in bulk polycondensation, giving poly(D,L-lactic acid) with average molecular weights (Mw) of (1.7–2.3) × 104 in high yield. Copyright © 2007 Society of Chemical Industry
Co-reporter:Zi-Qiang Lei;Yan-Bin Bai;Shou-Feng Wang
Journal of Applied Polymer Science 2007 Volume 105(Issue 6) pp:3597-3601
Publication Date(Web):5 JUN 2007
DOI:10.1002/app.26427
Poly(lactic acid) was synthesized from cheap, commercially available aqueous lactic acid (85–90% w/w) with ε-caprolactam and SnCl2·2H2O as catalysts in the absence of organic solvents. As a result, poly(lactic acid) with a molecular weight of 50,000 and a yield of 87–94% was prepared in 16 h. The new procedure is quite simple and cheap. The starting material is renewable aqueous lactic acid. The effects of the amount of the catalyst, the reaction temperature, and the reaction time on the polymerization were investigated in detail. The polymers obtained by ε-caprolactam and SnCl2·2H2O were characterized with gel permeation chromatography, infrared, and nuclear magnetic resonance. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Co-reporter:Zi-Qiang Lei, Shou-Xin Wen
Materials Letters 2007 Volume 61(19–20) pp:4076-4078
Publication Date(Web):August 2007
DOI:10.1016/j.matlet.2007.01.041
The polymerization of styrene on inorganic palygorskite nanorods was carried out by reverse atom transfer radical polymerization (RATRP) in a completely controlled manner to form structurally well-defined PS-grafted hybrid nanocomposite. Well-defined PS chains were grown from the nanoparticle surfaces to yield individual particles composed of a palygorskite core and a well-defined outer PS layer. It has been found that the dispersibility of palygorskite particles in organic solvents is significantly improved by grafting polymers onto the surface of palygorskite particles. So the holding time of PS-palygorskite is prolonged in organic solvents. Active point of adsorption in palygorskite surface is adequately utilized. The polymer-grafted palygorskite nanoparticles possess excellent decoloration capacity in organic solvents.
Co-reporter:Ziqiang Lei;Penghua Yan;Yaoxia Yang
Catalysis Letters 2007 Volume 118( Issue 1-2) pp:69-71
Publication Date(Web):2007 October
DOI:10.1007/s10562-007-9147-0
\(\begin{array}{l}{\hbox{R}^1\hbox{R}^2\hbox{CHOH}} \\ {\hbox{RCH}_2\hbox{OH} }\end{array} \dynrightarrow{Oxone}{\hbox{CH}_3\hbox{CN/H}_2\hbox{O}, 70^{\circ}\hbox{C}} \begin{array}{l}{\hbox{R}^1\hbox{R}^2\hbox{CO}} \\ {\hbox{RCOOH}} \end{array}\) A simple and environmentally friendly procedure for the oxidation of alcohols is presented utilizing Oxone® (2KHSO5 · KHSO4 · K2 SO4) as oxidant and polymer-supported 2-iodobenzamide as catalyst in CH3CN/H2O mixed solvents.
Co-reporter:Ziqiang Lei;Yaoxia Yang;Xiangzhen Bai
Advanced Synthesis & Catalysis 2006 Volume 348(Issue 7-8) pp:
Publication Date(Web):5 MAY 2006
DOI:10.1002/adsc.200505356
An effective, cheap, environmentally benign and catalyst-free oxidation of alcohols was carried out at room temperature using tetra-n-butylammonium Oxone® (TBA-OX) as oxidant with moderate to high selectivity for most of the alcohols using water as the solvent.
Co-reporter:Hongxia Ren;Yunpu Wang
Journal of Applied Polymer Science 2005 Volume 98(Issue 1) pp:315-321
Publication Date(Web):20 JUL 2005
DOI:10.1002/app.21897
The aromatic-aliphatic copolyamides were synthesized by condensation polymerization of aromatic diamine PPD (or APS, where PPD is p-phenylene diamine and APS is aminophenyl sulfone), aliphatic diamine HDA (or EDA, where HDA is hexanediamine and EDA is ethylenediamine), and TPC (where TPC is terephthalyl chloride) with different molar ratios of aromatic diamine to aliphatic diamine. The steady-state fluorescence of these condensed copolymers was investigated. These copolyamides exhibit strong blue-to-green fluorescence. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 315–321, 2005
Co-reporter:Zhen Guo;Hua Feng;Heng-chang Ma;Qiao-Xiang Kang;Zhi-Wang Yang
Polymers for Advanced Technologies 2004 Volume 15(Issue 1‐2) pp:100-104
Publication Date(Web):10 FEB 2004
DOI:10.1002/pat.448
To modify the surface of aminomethyl polystyrene, grafting of hyperbranched dendritic polyamidoamine, a new class of topological macromolecules, onto the surface was investigated. It was found that hyperbranched dendritic polyamidoamine was propagated from aminomethyl polystyrene surface by repeating two processes: (1) Michael addition; (2) amidation. Furthermore, salicylal (SA) readily postgrafted to the hyperbranched dendritic polyamidoamine-grafted-aminomethyl polystyrene. Finally, catalytic hydrogenations of pyrrole, furan and thiophene were investigated by the modifying polyamidoamine-grafted aminomethyl polystyrene with SA (MPGAPS)-supported palladium catalyst. The double-bond of the ring was hydrogenated to single-bond ring of tetrahydro-compound at first, then the ring is broken directly. In general, these reactions were degradation under reduction. UV absorbance spectroscopy, gas chromatography (GC), and power of hydrogen (PH) detection were used to analyze the reactants and products, and infrared (IR), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) characterized the catalyst. Copyright © 2004 John Wiley & Sons, Ltd.
Co-reporter:Jiande Gao, Qian Yang, Feitian Ran, Guofu Ma, Ziqiang Lei
Applied Clay Science (November 2016) Volumes 132–133() pp:739-747
Publication Date(Web):November 2016
DOI:10.1016/j.clay.2016.08.021
Co-reporter:Cui-Lin Li, Zhi-Wang Yang, Shang Wu, Zi-Qiang Lei
Reactive and Functional Polymers (January 2007) Volume 67(Issue 1) pp:53-59
Publication Date(Web):January 2007
DOI:10.1016/j.reactfunctpolym.2006.09.004
Co-reporter:Guofu Ma, Qian Yang, Feitian Ran, Zhibao Dong, Ziqiang Lei
Applied Clay Science (December 2015) Volume 118() pp:21-28
Publication Date(Web):December 2015
DOI:10.1016/j.clay.2015.09.001
Co-reporter:Dan Chai, Wei Wang, Wenkui Dong, Yumao Kang, Yinjuan Dong, Ziqiang Lei
Applied Catalysis A: General (5 September 2016) Volume 525() pp:1-8
Publication Date(Web):5 September 2016
DOI:10.1016/j.apcata.2016.06.035
Co-reporter:Jingchun Jia, Rongfang Wang, Hui Wang, Shan Ji, Julian Key, Vladimir Linkov, Kang Shi, Ziqiang Lei
Catalysis Communications (30 November 2011) Volume 16(Issue 1) pp:60-63
Publication Date(Web):30 November 2011
DOI:10.1016/j.catcom.2011.08.031
A new kind of carbon nitride (CNx)-Fe3O4 (Fe3O4-CNx) hybridized composition is fabricated by carbonizing polypyrrole-Fe3O4 hybridized precursor at 800 °C. Well-dispersed Pd nanoparticles with a narrow size distribution of 7–11 nm could be very easily prepared on the coraline-like CNx-Fe3O4. Due to the synergetic effect between the N-atom, Pd-atom and Fe3O4 species, the corresponding Pd/Fe3O4-CNx catalyst exhibits higher activity and better stability for the electrochemical oxidation of formic acid than either commercial Pd/C or Pt/C catalyst.The Fe3O4-CNx provided a novel support for Pd, with good durability and catalytic activity for formic acid oxidation.Download full-size imageHighlights► CNx modified Fe3O4 is prepared by a simple method. ► Fe3O4-CNx is a novel support for Pd towards oxidation of formic acid. ► Pd/Fe3O4-CNx has good durability and catalytic activity for oxidation of formic acid.
Co-reporter:Wei Wang, Wangli Jing, Li Sheng, Dan Chai, Yumao Kang, Ziqiang Lei
Applied Catalysis A: General (25 May 2017) Volume 538() pp:123-130
Publication Date(Web):25 May 2017
DOI:10.1016/j.apcata.2017.03.027
Co-reporter:Yun-Mei Zhong, Heng-Chang Ma, Jin-Xia Wang, Xiao-Jie Jia, Wen-Feng Li and Zi-Qiang Lei
Catalysis Science & Technology (2011-Present) 2011 - vol. 1(Issue 6) pp:NaN931-931
Publication Date(Web):2011/06/22
DOI:10.1039/C1CY00165E
AlBr3·6H2O was found to be an efficient catalyst in the field of oxidation of benzylic alcohols. Primary and secondary benzylic alcohols could be transformed into corresponding aldehydes and ketones with almost complete conversion and high selectivity. The non-transition metal related reaction systems have an incomparable advantage over others, such as easy work-up, excellent selectivity as well as commercial availability.
Co-reporter:Lijun Shi, Xiang Zhong, Houde She, Ziqiang Lei and Fuwei Li
Chemical Communications 2015 - vol. 51(Issue 33) pp:NaN7139-7139
Publication Date(Web):2015/03/16
DOI:10.1039/C5CC00249D
The Mn-catalyzed C–H alkenylation reactions of indole with terminal- and internal-alkynes have been developed. In the presence of a catalytic amount of acid, the procedure efficiently affords bis/trisubstituted indolyl-alkenes in a highly regio- and stereo-selective manner. Without the addition of acid, the reaction undergoes a [2+2+2] cyclization process to give carbazoles with release of hydrogen gas. Notably, the directing pyrimidyl group can be readily removed. Experimental studies reveal that the reaction is initiated by a C–H activation step and the acid is the selectivity controller via a hydrogen transfer process.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu and Ziqiang Lei
Journal of Materials Chemistry A 2014 - vol. 2(Issue 41) pp:NaN17301-17301
Publication Date(Web):2014/09/02
DOI:10.1039/C4TA03929G
A facile one-step activation and nitrogen-doping combination method is developed for preparation of nitrogen-doped graphene-like carbon nanosheets (N-CNSs). The N-CNSs have abundant wrinkled structures and ultrahigh pore volume (3.19 cm3 g−1), and are used as high-performance electrode materials for supercapacitors.
Co-reporter:Hengchang Ma, Zengming Yang, Haiying Cao, Lei Lei, Lu Chang, Yucheng Ma, Manyi Yang, Xiaoqiang Yao, Shaobo Sun and Ziqiang Lei
Journal of Materials Chemistry A 2017 - vol. 5(Issue 4) pp:NaN660-660
Publication Date(Web):2016/11/28
DOI:10.1039/C6TB02844F
Specific organelle imaging and long-term cellular tracking are of paramount importance in monitoring biological processes, pathological pathways, and therapeutic effects, etc. Herein, we report a novel macromolecule fluorescent probe (TPPA–DBO), which is synthesized from tris(4-(pyridin-4-yl)phenyl)amine (TPPA) and 1,8-dibromononane (DBO) with a gram scale by a simple method. TPPA–DBO demonstrates a highly specific nucleolus-targeting ability, which is very challenging in the bioimaging research field. We have shown that the green nucleolus-specificity probe TPPA–DBO has advantages over the commercially available nucleolus-staining probes such as DAPI, Hoechst dyes and SYTOs in terms of its AIE-performance, large Stokes shift (175 nm), excellent photostability, and promising usefulness in live cell imaging experiments. Surprisingly, after internalizing TPPA–DBO into the nucleus region for a period of time, some TPPA–DBO are reversely diffused from nucleolus into the cytoplasm, thus resulting in the staining of mitochondria with a redder emission color. This research result may provide a new concept of cellular tracker design and provide insight into biological questions, understanding disease mechanismss, and designing new therapeutic strategies.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Jingjing Mu, Hui Wang and Ziqiang Lei
Journal of Materials Chemistry A 2014 - vol. 2(Issue 10) pp:NaN3307-3307
Publication Date(Web):2013/12/02
DOI:10.1039/C3TA13859C
We have developed a supercapacitor electrode composed of CuS microspheres with polypyrrole (PPy) uniformly inserted into the sheet-like subunit structure and coated onto the CuS surface to enhance the pseudocapacitive performance. Novel sphere-like CuS particles with intertwined sheet-like subunit structure are fabricated by a solvothermal approach without any surfactant or template. A CuS@PPy composite electrode is prepared by in situ oxidation polymerization of pyrrole in the presence of the CuS suspension. The CuS@PPy composite (CuS content is 16.7 wt%) exhibits a high specific capacitance of 427 F g−1 (at 1 A g−1) and its capacitance can still retain 88% after 1000 cycles.
Co-reporter:Hui Peng, Guofu Ma, Jingjing Mu, Kanjun Sun and Ziqiang Lei
Journal of Materials Chemistry A 2014 - vol. 2(Issue 27) pp:NaN10388-10388
Publication Date(Web):2014/05/08
DOI:10.1039/C4TA01899K
Asymmetric supercapacitors (ASCs) with high energy density are assembled based on the pseudocapacitance of both electrodes, which use polyaniline (PANI) nanotubes as positive electrodes and MoO3 nanobelts as negative electrodes in a 1 M H2SO4 aqueous electrolyte. The assembled novel PANI//MoO3 ASC device with an extended operating voltage window of 2.0 V, in spite of the use of an aqueous electrolyte, exhibits excellent performance such as a high specific capacitance of 518 F g−1 at a current density of 0.5 A g−1, reaching an energy density as high as 71.9 W h kg−1 at a power density of 254 W kg−1 and good cycling stability.
Co-reporter:Hui Peng, Guofu Ma, Kanjun Sun, Zhiguo Zhang, Qian Yang, Feitian Ran and Ziqiang Lei
Journal of Materials Chemistry A 2015 - vol. 3(Issue 25) pp:NaN13214-13214
Publication Date(Web):2015/05/21
DOI:10.1039/C5TA03034J
Highly crumpled nitrogen-doped graphene-like nanosheets (CN-GLSs) with a high specific surface area (1169 m2 g−1) and large pore volume (2.58 cm3 g−1) are prepared from a macroporous resin via simultaneous urea gasification expansion and CaCl2 activation methods. The CN-GLSs are tested as electrodes for supercapacitors and present excellent electrochemical performance.
Co-reporter:Guofu Ma, Miaomiao Dong, Kanjun Sun, Enke Feng, Hui Peng and Ziqiang Lei
Journal of Materials Chemistry A 2015 - vol. 3(Issue 7) pp:NaN4041-4041
Publication Date(Web):2015/01/06
DOI:10.1039/C4TA06322H
A stable and effective redox-mediator gel electrolyte has been prepared by doping indigo carmine (IC) into a polyvinyl alcohol sulfuric acid polymer system (PVA–H2SO4), and a high performance solid state supercapacitor is fabricated by utilizing activated carbon as electrodes and the prepared gel polymer (PVA–H2SO4–IC) as an electrolyte and separator. The PVA–H2SO4–IC gel polymer has excellent bending, compressing and stretching mechanical properties. As expected, the ionic conductivity of the gel polymer electrolyte increased by 188% up to 20.27 mS cm−1 while introducing IC as the redox mediator in the PVA–H2SO4 gel electrolyte. Simultaneously, specific capacitance is increased by 112.2% (382 F g−1) and energy density (13.26 W h kg−1) is also increased. Furthermore, the fabricated device shows superior charge–discharge stability. After 3000 cycles, its capacitive retention ratio is still as high as 80.3%. This result may be due to the fact that the IC can act as a plasticizer and redox mediator, and the supercapacitor combines the double-layer characteristic of carbon-based supercapacitors and the faradaic reaction characteristic of batteries energy-storage processes.
Co-reporter:Hui Lv, Qi Xing, Chengtao Yue, Ziqiang Lei and Fuwei Li
Chemical Communications 2016 - vol. 52(Issue 39) pp:NaN6548-6548
Publication Date(Web):2016/04/15
DOI:10.1039/C6CC01234E
An unprecedented catalyst-free formylation of amines using CO2 and hydrosilanes was developed. The solvent plays a vital role in promoting the interaction of amines with hydrosilanes and subsequent CO2 insertion, thus facilitating the simultaneous activation of N–H and Si–H bonds. Based on relevant mechanistic studies, a plausible mechanism involving a silyl carbamate intermediate is proposed.
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