Co-reporter:Xingtao Xu, Jing Tang, Huayu Qian, Shujin Hou, Yoshio Bando, Md. Shahriar A. Hossain, Likun Pan, and Yusuke Yamauchi
ACS Applied Materials & Interfaces November 8, 2017 Volume 9(Issue 44) pp:38737-38737
Publication Date(Web):October 30, 2017
DOI:10.1021/acsami.7b09944
Metal–organic frameworks (MOFs) with high porosity and a regular porous structure have emerged as a promising electrode material for supercapacitors, but their poor electrical conductivity limits their utilization efficiency and capacitive performance. To increase the overall electrical conductivity as well as the efficiency of MOF particles, three-dimensional networked MOFs are developed via using preprepared conductive polypyrrole (PPy) tubes as the support for in situ growth of MOF particles. As a result, the highly conductive PPy tubes that run through the MOF particles not only increase the electron transfer between MOF particles and maintain the high effective porosity of the MOFs but also endow the MOFs with flexibility. Promoted by such elaborately designed MOF–PPy networks, the specific capacitance of MOF particles has been increased from 99.2 F g–1 for pristine zeolitic imidazolate framework (ZIF)-67 to 597.6 F g–1 for ZIF–PPy networks, indicating the importance of the design of the ZIF–PPy continuous microstructure. Furthermore, a flexible supercapacitor device based on ZIF–PPy networks shows an outstanding areal capacitance of 225.8 mF cm–2, which is far above other MOFs-based supercapacitors reported up to date, confirming the significance of in situ synthetic chemistry as well as the importance of hybrid materials on the nanoscale.Keywords: conductive polymer; flexibility; in situ synthesis; metal−organic frameworks; supercapacitor;
Co-reporter:Likun Pan;Ting Lu;Dong Yan;Yefeng Yao;Jinliang Li;Wei Qin
ACS Applied Materials & Interfaces January 25, 2017 Volume 9(Issue 3) pp:2309-2316
Publication Date(Web):December 29, 2016
DOI:10.1021/acsami.6b12529
Currently sodium-ion batteries (SIBs) as energy storage technology have attracted lots of interest due to their safe, cost-effective, and nonpoisonous advantages. However, many challenges remain for development of SIBs with high specific capacity, high rate capability, and long cycle life. Therefore, CuS as an important earth-abundant, low-cost semiconductor was applied as anode of SIBs with ether-based electrolyte instead of conventional ester-based electrolyte. By incorporating reduced graphene oxide (RGO) into CuS nanosheets and optimizing the cutoff voltage, it is found that the sodium-ion storage performance can be greatly enhanced using ether-based electrolyte. The CuS-RGO composites deliver an initial Coulombic efficiency of 94% and a maximum specific capacity of 392.9 mAh g–1 after 50 cycles at a current density of 100 mA g–1. And a specific capacity of 345 mAh g–1 is kept after 450 cycles at a current density of 1 A g–1. Such an excellent electrochemical performance is ascribed to the conductive network construction of CuS-RGO composites, the suppression of dissolved polysulfide intermediates by using ether-based electrolyte, and the avoidance of conversion-type reaction by optimizing the cutoff voltage.Keywords: CuS; cutoff voltage; ether-based electrolyte; reduced graphene oxide; sodium-ion batteries;
Co-reporter:Jiabao Li, Dong Yan, Ting Lu, Yefeng Yao, Likun Pan
Chemical Engineering Journal 2017 Volume 325(Volume 325) pp:
Publication Date(Web):1 October 2017
DOI:10.1016/j.cej.2017.05.046
•A novel composite containing CoSe and porous carbon polyhedra was fabricated.•The composite was used as anodes of lithium ion batteries and sodium ion batteries.•The composite exhibits high specific capacity and superior cycling stability.A novel composite containing CoSe and porous carbon polyhedra (PCP), denoted as CoSe@PCP, was successfully synthesized using Co-based zeolitic imidazolate framework (ZIF-67) as precursor through a two-step method, including carbonization of ZIF-67 and subsequent selenization. The field-emission scanning electron microscopy and transmission electron microscopy characterizations confirm that CoSe nanoparticles are uniformly dispersed in PCP. When the CoSe@PCP was used as anode material for lithium-ion batteries, it exhibits superior performance with a high reversible capacity of 675 mAh g−1 at 200 mA g−1 after 100 cycles and 708.2 mAh g−1 at 1 A g−1 after 500 cycles as well as excellent cycling stability. Additionally, the CoSe@PCP also demonstrates excellent performance as anode material for sodium-ion batteries. A reversible capacity of 341 mAh g−1 can be obtained over 100 cycles at 100 mA g−1 with high cycling stability. The excellent battery performance of CoSe@PCP should be attributed to the synergistic effect of nanostructured CoSe and PCP derived from ZIF-67, in which the nanostructured CoSe possesses high reactivity towards lithium and sodium ions and the PCP can provide a continuous conductive matrix to facilitate the charge transfer and an effective buffering to mitigate the structure variation of CoSe during cycling.Download high-res image (111KB)Download full-size image
Co-reporter:Xingtao Xu, Miao Wang, Yong Liu, Ting Lu, and Likun Pan
ACS Sustainable Chemistry & Engineering 2017 Volume 5(Issue 3) pp:
Publication Date(Web):February 17, 2017
DOI:10.1021/acssuschemeng.7b00463
Co-reporter:Jinliang Li, Xingtao Xu, Xinjuan Liu, Wei Qin, Miao Wang, Likun Pan
Journal of Alloys and Compounds 2017 Volume 690(Volume 690) pp:
Publication Date(Web):5 January 2017
DOI:10.1016/j.jallcom.2016.08.176
•Photocatalysis is an environmental-friendly technology for nitrobenzene removal.•Cake-like anatase/rutile TiO2 is fabricated by pyrolyzing metal-organic frameworks.•It exhibits excellent photocatalytic performance in degradation of nitrobenzene.•A high degradation rate of 97% in 100 min is achieved under UV light irradiation.Cake-like anatase/rutile mixed phase TiO2 (A/R TiO2) was successfully prepared through pyrolyzation of metal-organic frameworks MIL-125. Its morphology, structure and photocatalytic performance for degradation of nitrobenzene under UV light irradiation were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, nitrogen adsorption-desorption isotherms, UV–Vis absorption spectroscopy, photocurrent and photoluminescence spectroscopy, respectively. The results show that the cake-like A/R TiO2 exhibits excellent photocatalytic performance with a maximum nitrobenzene degradation rate of 97% and corresponding mineralization rate of 77% at 100 min under UV light irradiation, which is better than those of cake-like rutile TiO2 and anatase TiO2. The improved photocatalytic performance is ascribed to the reduced electron-hole pair recombination in cake-like A/R TiO2.
Co-reporter:Dong Yan, Caiyan Yu, Xiaojie Zhang, Jiabao Li, Junfeng Li, Ting Lu, Likun Pan
Electrochimica Acta 2017 Volume 254(Volume 254) pp:
Publication Date(Web):10 November 2017
DOI:10.1016/j.electacta.2017.09.120
The main challenge of using TiO2 as anode for sodium-ion batteries (SIBs) is its inherent low electrical conductivity, which leads to its unsatisfied capacity, short cycle life and low initial Coulombic efficiency. Herein, we report that synergistically doped anatase TiO2 nanotubes with Ni and N via a simple sol-gel process, subsequent alkali-thermal reaction, and final thermal treatment in NH3 can optimize the relationship among the phase structure, electrical conductivity and sodium-ion diffusion kinetic performance of anatase TiO2 to enhance its sodium-ion storage and transport performances. The resultant Ni and N co-doped anatase TiO2 nanotubes (Ni-N/TNTs) exhibit a high charge capacity of 303 mA h g−1 after 500 cycles at a current density of 50 mA g−1 with an initial Coulombic efficiency of 65% and even at a high current density of 5 A g−1, a capacity of 143 mA h g−1 is maintained after 8000 cycles with a capacity retention of ≥100%. The bandgap estimation, phase structure evolution, and electrochemical impedance spectroscopy analysis combined with the electrochemical test results indicate that the significantly improved sodium-ion storage and transport performances of Ni-N/TNTs should be mainly ascribed to the increased electrical conductivity, stable phase structure during the electrochemical processes, lower charge transfer resistance, and enhanced sodium-ion diffusion coefficient after Ni and N co-doping. The high capacity, improved Coulombic efficiency, excellent rate performance and long cycle life enable Ni-N/TNTs to be an applicable anode material for SIBs.
Co-reporter:Hongmei Tang, Dong Yan, Ting Lu, Likun Pan
Electrochimica Acta 2017 Volume 241(Volume 241) pp:
Publication Date(Web):1 July 2017
DOI:10.1016/j.electacta.2017.04.112
In this work, sulfur-doped carbon spheres with hierarchical micro/mesopores (denoted as S-MCSs) were fabricated via a sol-gel method combined with surfactant-directing assembly strategy and subsequent sulfuration process. When used as anode materials of sodium-ion batteries (SIBs), S-MCSs show excellent electrochemical performance with a high maximum reversible capacity of 443.4 mA h g−1 after 50 cycles at 50 mA g−1, and even at a high current density of 1 A g−1, a reversible capacity of 238.2 mA h g−1 is obtained after 600 cycles, mainly due to their hierarchical micro/mesoporous structure with high specific surface area, large pore volume and high sulfur content. The excellent cycling performance and high capacity enable the S-MCSs to be a promising candidate for SIBs.
Co-reporter:Jiabao Li, Dong Yan, Xiaojie Zhang, Shujin Hou, Dongsheng Li, Ting Lu, Yefeng Yao, Likun Pan
Electrochimica Acta 2017 Volume 228(Volume 228) pp:
Publication Date(Web):20 February 2017
DOI:10.1016/j.electacta.2017.01.114
Novel Sb2S3@multiwalledcarbonnanotubes(MWCNTs) (SM) composites were synthesized via a facile and green method which included an in-situ growth of Sb2S3 nanoparticles on the surface of MWCNTs through precipitation and subsequent thermal treatment. The morphologies and structures of SM composites were tested by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and nitrogen adsorption and desorption isotherms. Finally, their application as anode materials for sodium-ion batteries (SIBs) was investigated through corresponding electrochemical measurements such as galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. The results show that the SM composites display higher capacity, better cycling stability and superior rate performance than pure Sb2S3, and a capacity of 412.3 mAh g−1 after 50 cycles at 50 mA g−1 is obtained for SM composites with 30 wt.% MWCNTs loading. The enhanced performance is ascribed to an increase in the specific surface area, an improvement in the charge transfer and effective buffering of the volume change offered by the porous conductive network structure of the composite with the introduction of MWCNTs.
Co-reporter:Xiaojie Zhang, Dongsheng Li, Guang Zhu, Ting Lu, Likun Pan
Journal of Colloid and Interface Science 2017 Volume 499(Volume 499) pp:
Publication Date(Web):1 August 2017
DOI:10.1016/j.jcis.2017.03.104
Recently sodium ion batteries (SIBs) as a new energy storage system have attracted enormous interests. Unfortunately, the development of high-performance electrode materials for SIBs is restricted owing to the large volume change during sodium insertion and extraction. In this work, porous CoFe2O4 nanocubes (PCFO-NCs) were prepared simply by annealing metal-organic frameworks and used as anode materials for SIBs. The PCFO-NCs exhibit a high initial Coulombic efficiency of 68.8% and a maximum reversible capacity of 360 mAh g−1 after 50 cycles at the current density of 50 mA g−1, as well as good rate capability and excellent cycling stability at high current density. The excellent electrochemical performance can be attributed the short diffusion distance of sodium ion due to the good interfacial contact between electrode and electrolyte, and the buffering of volume change during charge/discharge processes by the porous structure.Download high-res image (220KB)Download full-size image
Co-reporter:Jiabao Li;Dong Yan;Xiaojie Zhang;Shujin Hou;Ting Lu;Yefeng Yao
Journal of Materials Chemistry A 2017 vol. 5(Issue 38) pp:20428-20438
Publication Date(Web):2017/10/03
DOI:10.1039/C7TA06180C
Rational fabrication and structure design of anode materials with high specific capacity and excellent cycling stability are of significant importance for the development of high-performance lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). In this paper, a zeolitic imidazolate framework-8 (ZIF-8) with a unique polyhedral morphology and large size (about 2 μm) was successfully synthesized through a facile co-precipitation method. After successive carbonization and sulfidation, ZnS nanoparticles decorated on nitrogen-doped porous carbon polyhedra (ZnS/NPC) were obtained. When applied as the anode material for LIBs, the ZnS/NPC hybrid displays the highest reversible specific capacity for ZnS-based electrodes reported so far (1067.4 mA h g−1 at 0.1 A g−1 after 200 cycles), excellent rate capability (364.6 mA h g−1 at 4 A g−1), and robust long-term cycling performance (856.8 mA h g−1 at 1 A g−1 after 1000 cycles). As for SIBs, the resultant ZnS/NPC also exhibits a desirable capacity of 370.6 mA h g−1 after 100 cycles at 0.1 A g−1 and 289.2 mA h g−1 after 1000 cycles at 1 A g−1. Such superior lithium and sodium storage performances should be attributed to the distinctive structure advantages inherited from ZIF-8, where the Zn ions were in situ converted to ZnS with high reactivity upon electrochemical cycling and the organic linkers were pyrolyzed to nitrogen-doped porous carbon polyhedra to enhance the conductivity of the hybrid and keep the structure stability during cycling.
Co-reporter:Shujin Hou;Xingtao Xu;Miao Wang;Yingqiao Xu;Ting Lu;Yefeng Yao
Journal of Materials Chemistry A 2017 vol. 5(Issue 36) pp:19054-19061
Publication Date(Web):2017/09/19
DOI:10.1039/C7TA04720G
Transition metal phosphides, especially Ni2P, are of great interest as promising battery-type electrode materials for hybrid supercapacitors, but their poor electrical conductivity and porosity limit their application. Here, for the first time, the synthesis of carbon-incorporated Janus-type Ni2P/Ni hollow spheres (Ni2P/Ni/C) was reported via simultaneous carbonization and phosphorization of Ni-based metal–organic frameworks (Ni-MOFs). Their unique structural merits include the incorporated carbon content, Janus-type Ni2P/Ni nanocrystals, and high-porosity hollow structure, thus endowing them with a high specific surface area, good electrical conductivity and low density. As a result, the optimized Ni2P/Ni/C exhibits a remarkable specific capacitance of 1449 F g−1 at 1 A g−1 in 2 M KOH aqueous electrolyte in a three-electrode system. A hybrid supercapacitor device was fabricated by using Ni2P/Ni/C as the positive electrode and active carbon as the negative electrode, and it achieves a very high energy density of 32.02 W h kg−1 at a power density of 700 W kg−1 and a remarkable cycling stability (about 99% capacitance retention after 5000 cycles). The Ni2P/Ni/C should be one of the most promising electrode materials for hybrid supercapacitor application.
Co-reporter:Xingtao Xu, Miao Wang, Yong Liu, Ting Lu, and Likun Pan
ACS Sustainable Chemistry & Engineering 2017 Volume 5(Issue 1) pp:
Publication Date(Web):November 23, 2016
DOI:10.1021/acssuschemeng.6b01212
Flow-electrode capacitive deionization (FCDI) is an emerging desalinization technology for high-concentration saline water treatment. However, in practical cases the operation voltage of FCDI is usually limited by the decomposition potential of water (1.23 V), which does harm the desalinization performance of FCDI. To address this issue, here for the first time we propose a novel asymmetric FCDI (AFCDI) device by using an activated carbon (AC)/MnO2 suspension as the positive electrode and AC suspension as the negative electrode. In AFCDI, the operation voltage can be improved to be 1.8 V, and a high salt removal efficiency of 78% is achieved in 0.1 M NaCl solution within 2 h, much higher than that for conventional FCDI (59%). To the best of knowledge, this value is also much higher than those for other FCDI devices reported previously. The present work may provide a promising high-performance desalinization device for high-concentration saline water treatment.Keywords: Asymmetric flow-electrode capacitive deionization; Desalinization; High-concentration saline water treatment; Operation voltage;
Co-reporter:Xiaojie Zhang, Guang Zhu, Dong Yan, Ting Lu, Likun Pan
Journal of Alloys and Compounds 2017 Volume 710(Volume 710) pp:
Publication Date(Web):5 July 2017
DOI:10.1016/j.jallcom.2017.03.314
•MnO@C nanorods were synthesized from metal organic frameworks precursor.•MnO@C nanorods were used as anode materials of sodium ion batteries.•MnO@C nanorods display high specific capacity and superior long-cycling stability for 5000 cycles.Porous MnO@C nanorods were synthesized simply by annealing Mn-based metal-organic frameworks precursor. The morphology, structure and electrochemical performance of MnO@C hybrid were characterized by scanning electron microscopy, nitrogen adsorption/desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impendence spectroscopy. When used as anode material for sodium-ion batteries, the MnO@C hybrid exhibits a high reversible specific capacity of 260 mAh g−1 after 100 cycles at a current density of 50 mA g−1. When the current density is increased to 2 A g−1, the MnO@C delivers a superior long-life cycling performance with a capacity of 140 mAh g−1 at very high current density of 2 A g−1. The excellent electrochemical performance of MnO@C can be attributed to its unique porous structure with MnO nanoparticles embedded in carbon matrix, which can apparently increase the electrical conductivity and buffer the volume change during the charge/discharge process.
Co-reporter:Dong Yan, Caiyan Yu, Dongsheng Li, Xiaojie Zhang, Jiabao Li, Ting Lu and Likun Pan
Journal of Materials Chemistry A 2016 vol. 4(Issue 28) pp:11077-11085
Publication Date(Web):20 Jun 2016
DOI:10.1039/C6TA04906K
TiO2 is a promising anode for sodium-ion batteries (SIBs) due to its inherent safety, low cost, good structural stability during the sodium-ion storage process and appropriate voltage platform. However, unsatisfactory electrical conductivity hinders its applications. Here we demonstrate that doping TiO2 nanotubes with Ni2+via an initial sol–gel method, subsequent hydrothermal process and final thermal treatment can balance the high conductivity and good structural stability of TiO2 to improve the sodium-ion storage performance. The resultant sample exhibits a high charge capacity of 286 mA h g−1 after 100 cycles at a current density of 50 mA g−1 and even at a high current density of 5 A g−1, a capacity of 123 mA h g−1 is maintained after 2000 cycles. It is believed that the strategy in this work can provide a useful pathway towards enhancing the electrochemical performance of TiO2 anodes for SIBs.
Co-reporter:Xingtao Xu, Miao Wang, Yong Liu, Ting Lu and Likun Pan
Journal of Materials Chemistry A 2016 vol. 4(Issue 15) pp:5467-5473
Publication Date(Web):14 Mar 2016
DOI:10.1039/C6TA00618C
Capacitive deionization (CDI) is an emerging desalination technique to offer clean water. In order to obtain high CDI performance, a rationally designed structure of electrode materials has been an urgent need for CDI application. Here for the first time a hierarchical porous carbon nanotube (CNT)/porous carbon polyhedra (PCP) (hCNT/PCP) hybrid was fabricated via in situ insertion of CNTs into ZIF-8 and a subsequent pyrolysis process. The potential of the hCNT/PCP hybrid for CDI application was demonstrated, and the results indicate that the hCNT/PCP hybrid exhibits a high electrosorption capacity of 20.5 mg g−1 with stable cycling stability due to its novel CNT-inserted-PCP porous structure, high specific surface area and good electrical conductivity. It should be expected that hCNTs/PCP should be a promising candidate for highly efficient CDI electrode materials.
Co-reporter:Dong Yan, Xingtao Xu, Ting Lu, Bingwen Hu, Daniel H.C. Chua, Likun Pan
Journal of Power Sources 2016 Volume 316() pp:132-138
Publication Date(Web):1 June 2016
DOI:10.1016/j.jpowsour.2016.03.050
•Graphene/carbon nanotubes sponge was fabricated via a simple freeze drying method.•The hybrid sponge was employed as anode materials of sodium ion batteries.•The hybrid sponge exhibits high capacity and superior long life cycling stability.Reduced graphene oxide/carbon nanotubes (CNTs) sponge (GCNTS) is fabricated via a simple freeze drying of graphene oxide/CNTs mixed solution and subsequent thermal treatment in nitrogen atmosphere, and used as anodes for sodium-ion batteries (SIBs) for the first time. The morphology, structure and electrochemical performance of GCNTS are characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, nitrogen adsorption-desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The results show that GCNTS with 20 wt % CNTs has a highest charge capacity of 436 mA h g−1 after 100 cycles at a current density of 50 mA g−1 and even at a high current density of 10 A g−1, a capacity of 195 mA h g−1 is maintained after 7440 cycles. The high capacity, excellent rate performance and long life cycling enable the GCNTS to be a promising candidate for practical SIBs.
Co-reporter:Miao Wang, Xingtao Xu, Yong Liu, Yanjiang Li, Ting Lu, Likun Pan
Carbon 2016 Volume 108() pp:433-439
Publication Date(Web):November 2016
DOI:10.1016/j.carbon.2016.07.047
Capacitive deionization (CDI) is an emerging desalination technology that has attracted wide attention. Generally, porous carbons with high specific surface area are considered as ideal electrode materials for CDI application. Despite the progress achieved to date, synthesis of porous carbons with a controllable specific surface area has rarely succeeded. To address this issue, here a new strategy to prepare high-performance CDI electrode materials was proposed by direct carbonization of Zn-containing metal-organic frameworks (MOFs). The results indicate that through controlling Zn/C ratio in MOFs, the resultant porous carbons display a controllable specific surface area, and thus exhibit a superior electrosorption performance. It should be believed that the strategy in this work will provide an effective route to prepare high-performance CDI electrode materials.
Co-reporter:Wei Qin, Taiqiang Chen, Ting Lu, Daniel H.C. Chua, Likun Pan
Journal of Power Sources 2016 Volume 302() pp:202-209
Publication Date(Web):20 January 2016
DOI:10.1016/j.jpowsour.2015.10.064
•Layered nickel sulfide-reduced graphene oxide composites were synthesized.•The composites were applied as anode materials of sodium-ion batteries.•The composites exhibit high specific capacity and good cycling performance.Layered nickel sulfide (NS)-reduced graphene oxide (RGO) composites are prepared via a simple microwave-assisted method and subsequent annealing in N2/H2 atmosphere. A detailed array of characterization tools are used to study their morphology, structure and electrochemical performance. It was found that these composites exhibit significantly improved sodium-ion storage ability as compared with pure NS under galvanostatic cycling at a specific current of 100 mA g−1 in a potential limitation of 0.005–3.0 V. Furthermore, the composite with the RGO content of 35 wt.% achieves a high maximum reversible specific capacity of about 391.6 mAh g−1 at a specific current of 100 mA g−1 after 50 cycles. These results prove that NS-RGO composites are highly promising when applied directly as anode materials in sodium-ion batteries.
Co-reporter:Miao Wang, Shujin Hou, Yong Liu, Xingtao Xu, Ting Lu, Ran Zhao, Likun Pan
Electrochimica Acta 2016 Volume 216() pp:211-218
Publication Date(Web):20 October 2016
DOI:10.1016/j.electacta.2016.09.026
Capacitive neutralization deionization with flow electrodes (FCND) was proposed by combining neutralization dialysis (ND) and flow-electrode capacitive deionization (FCDI). Its key property is that by employing flow electrodes, capacitive adsorption of salt ions occurs simultaneously during the neutralization dialysis process. To compare the desalination performance between FCND and FCDI, a series of experiments were conducted by changing salt concentration and applied electrical voltage. The hybrid exhibits a promising average salt adsorption rate (ASAR) and salt removal efficiency (SRE) compared to either ND or FCDI process. The ASAR and SRE of FCND are 203.27 mmol m−2 min−1 and 72.20% in 0.1 mM NaCl solution at 1.2 V after 120 min, whereas the values of FCDI are 120.86 mmol m−2 min−1 and 42.92%, respectively. In order to facilitate the understanding of the ion transportation in this complex system, a theory was also set up based on simplified Nernst-Planck equation and Donnan equilibrium, which helps to understand the experimental data.
Co-reporter:Xian Hou, Tongtong Xuan, Hengchao Sun, Xiaohong Chen, Huili Li, Likun Pan
Solar Energy Materials and Solar Cells 2016 Volume 149() pp:121-127
Publication Date(Web):May 2016
DOI:10.1016/j.solmat.2016.01.021
•ZnGa2O4:Eu3+ nanophosphor is used in mesoporous TiO2 of perovskite solar cells.•The nanophosphor improves the light absorption and exciton generation rate.•The nanophosphor increases the cell photocurrent and efficiency.•An extremely high photocurrent density of 25.02 mA cm−2 is achieved.ZnGa2O4:Eu3+ nanophosphor was synthesized through a hydrothermal method and used as an effective light down-shifting/converting material in mesoporous TiO2 layer of perovskite solar cells (PSCs). The nanophosphor can convert the high energy incident photon into the photon(s) with lower energy, which can excite CH3NH3PbI3 to generate more photo generated electron–hole pairs, and thus promote the incident light use ratio and increase the power conversion efficiency (PCE) of PSCs. After the incorporation of suitable amount of ZnGa2O4:Eu3+ into PSCs, the cell PCE is increased to 13.80% with a photocurrent density of 23.68 mA cm−2 and a highest PCE of 14.34% with a photocurrent density of 25.02 mA cm−2 is achieved, much higher than those of the cell without ZnGa2O4:Eu3+ (PCE of 10.67% and photocurrent density of 20.2 mA cm−2). The enhanced photovoltaic performance by incorporating the nanophosphor into PSCs should be ascribed to the increased incident light use ratio and improved exciton generation rate.
Co-reporter:Xingtao Xu, Yong Liu, Miao Wang, Cheng Zhu, Ting Lu, Ran Zhao, Likun Pan
Electrochimica Acta 2016 Volume 193() pp:88-95
Publication Date(Web):1 March 2016
DOI:10.1016/j.electacta.2016.02.049
One of the most challenging issues in developing supercapacitor and capacitive deionization (CDI) technologies is the rational design and synthesis of active electrode materials, with favorable morphologies, reasonable porous structure and high surface area. Recently, three-dimensional (3D) graphene frameworks (3DGF)-based hybrids have been considered as one of the most promising candidates for supercapacitor and CDI applications. By incorporating functional nanomaterials into 3DGF, the obtained 3DGF-based hybrids exhibited enhanced properties or unique character compared to 3DGF. Here we report novel hierarchical hybrids with microporous carbon spheres (MCS) decorated 3DGF (3DGF-MCS), which not only possesses a hierarchical porous structure, but also maintains favorable features for supercapacitor and CDI applications, such as a large surface area and good electrical conductivity. The results indicate that 3DGF-MCS with 10 wt% MCS exhibits excellent electrochemical performances, including a superior specific capacitance of 288.77 F g⿿1, and an ultrahigh electrosorption capacity of 19.8 mg g⿿1. The 3DGF-MCS should be promising electrode materials for highly efficient supercapacitor and CDI applications.
Co-reporter:Wei Qin, Dongsheng Li, Xiaojie Zhang, Dong Yan, Bingwen Hu, Likun Pan
Electrochimica Acta 2016 Volume 191() pp:435-443
Publication Date(Web):10 February 2016
DOI:10.1016/j.electacta.2016.01.116
ZnS nanoparticles embedded in reduced graphene oxide (RGO) were prepared via a facile microwave-assisted method and applied as anode materials of sodium-ion batteries (SIBs). The as-prepared composites exhibit excellent sodium storage properties. A maximum specific capacity of 481 mAh g−1 at the specific current of 100 mA g−1 can be achieved after 50 cycles by optimizing the RGO content in the composites. The improved sodium-ion storage ability can be ascribed to the enhanced specific surface area and increased electric conductivity due to the introduction of RGO and the decreased size of ZnS particles which can shorten the pathway of sodium-ion diffusion and facilitate the reversible Na+ diffusion kinetics.
Co-reporter:Dong Yan, Caiyan Yu, Xiaojie Zhang, Wei Qin, Ting Lu, Bingwen Hu, Huili Li, Likun Pan
Electrochimica Acta 2016 Volume 191() pp:385-391
Publication Date(Web):10 February 2016
DOI:10.1016/j.electacta.2016.01.105
Nitrogen-doped carbon microspheres (NCSs) derived from oatmeal are employed as anodes for sodium ion batteries (SIBs). Their morphology, structure and electrochemical performance are characterized by field emission scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, nitrogen adsorption-desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The results show that NCSs treated at 500 °C exhibit a high maximum charge capacity of 336 mA h g−1 after 50 cycles at a current density of 50 mA g−1 and even at a high current density of 10 A g−1 within 70 s charging time, a capacity of 104 mA h g−1 is maintained after 12500 cycles without obvious decay. The high capacity, excellent rate performance, long life cycling and ultrafast rechargeable ability enable the NCSs to be a promising candidate for practical SIBs.
Co-reporter:Xingtao Xu, Yong Liu, Miao Wang, Xiaoxia Yang, Cheng Zhu, Ting Lu, Ran Zhao, Likun Pan
Electrochimica Acta 2016 Volume 188() pp:406-413
Publication Date(Web):10 January 2016
DOI:10.1016/j.electacta.2015.12.028
•Mesoporous graphene was prepared via carbothermal reaction in nitrogen atmosphere.•Mesoporous graphene was used as electrode material for capacitive deionization.•Mesoporous graphene exhibits better deionization performance than graphene.Here a facile strategy was proposed to prepare graphene (GE) sheets with unique mesoporous morphology (denoted as mGE) via a simple carbothermal reaction by using KMnO4 as the etching agent. The morphology, structure and electrochemical properties of mGE were investigated by scanning electron microscopy, transmission electron microscopy, Raman spectra, nitrogen adsorption-desorption, cyclic voltammetry and electrochemical impedance spectroscopy. The electrosorption performance of mGE in NaCl solution was studied and compared with GE. The results show that mGE electrode exhibits a high electrosorption capacity of 6.38 mg g−1 when the initial NaCl concentration is ∼75 mg L−1 and applied voltage is 1.2 V, which is about 2.3 and 1.5 times of those of GE (2.76 mg g−1) and recently reported microporous GE (∼4 mg g−1), respectively, and also higher than those of other carbon materials in the literatures, due to short ion diffusion path, large accessible surface area and low charge transfer resistance offered by its novel mesoporous structure. Therefore, it is believed that mGE is a promising candidate for practical capacitive deionization applications.
Co-reporter:Jinliang Li, Xinjuan Liu, Zhuo Sun, Likun Pan
Journal of Colloid and Interface Science 2016 Volume 463() pp:145-153
Publication Date(Web):1 February 2016
DOI:10.1016/j.jcis.2015.10.055
Novel Bi2MoO6/TiO2 heterostructure microspheres were successfully synthesized via a facile solvothermal method. Their morphology, structure and photocatalytic performance in the degradation of phenol and nitrobenzene were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, electrochemical impedance spectra, UV–vis absorption spectroscopy and total organic carbon analyser, respectively. The results show that the Bi2MoO6/TiO2 heterostructures exhibit excellent photocatalytic performance with maximum phenol and nitrobenzene degradation rates of 96% and 94% and corresponding mineralization rates of 66% and 61% in 300 min under visible light irradiation, respectively. The improved photocatalytic performance is mainly ascribed to the reduced electron–hole pair recombination with the introduction of TiO2.
Co-reporter:Dongsheng Li, Dong Yan, Jiaqi Ma, Wei Qin, Xiaojie Zhang, Ting Lu, Likun Pan
Ceramics International 2016 Volume 42(Issue 14) pp:15634-15642
Publication Date(Web):1 November 2016
DOI:10.1016/j.ceramint.2016.07.017
Abstract
Sb2O3/reduced graphene oxide (RGO) composites were prepared through a facile microwave-assisted reduction of graphite oxide in SbCl3 precursor solution, and investigated as anode material for sodium-ion batteries (SIBs). The experimental results show that a maximum specific capacity of 503 mA h g−1 is achieved after 50 galvanostatic charge/discharge cycles at a current density of 100 mA g−1 by optimizing the RGO content in the composites and an excellent rate performance is also obtained due to the synergistic effect between Sb2O3 and RGO. The high capacity, superior rate capability and excellent cycling performance of Sb2O3/RGO composites demonstrate their excellent sodium-ion storage ability and show their great potential as electrode materials for SIBs.
Co-reporter:Jinliang Li, Xingtao Xu, Xinjuan Liu, Caiyan Yu, Dong Yan, Zhuo Sun, Likun Pan
Journal of Alloys and Compounds 2016 Volume 679() pp:454-462
Publication Date(Web):15 September 2016
DOI:10.1016/j.jallcom.2016.04.080
•Photocatalysis is an environmental-friendly technology for nitrobenzene removal.•Sn doped TiO2 nanotube with oxygen vacancy is fabricated for the first time.•It exhibits excellent photocatalytic performance in degradation of nitrobenzene.•A high degradation rate of 92% is achieved under visible light irradiation.Sn doped TiO2 nanotube with oxygen vacancy (Vo-SnTiO2) was successfully synthesized via a facile hydrothermal process and subsequent annealing in nitrogen atmosphere. The morphology, structure and photocatalytic performance of Vo-SnTiO2 in the degradation of nitrobenzene were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, UV–vis absorption spectroscopy, nitrogen adsorption-desorption and electrochemical impedance spectra, respectively. The inner diameter, outer diameter and specific surface area of Vo-SnTiO2 are about 5 nm, 15 nm and 235.54 m2 g−1, respectively. The experimental results show that the Vo-SnTiO2 exhibits excellent photocatalytic performance with a maximum degradation rate of 92% in 300 min for nitrobenzene and 94% in 100 min for Rhodamine B and corresponding mineralization rates of 68% and 70% under visible light irradiation. The improved photocatalytic performance is ascribed to the enhanced light absorption and specific surface area as well as the reduced electron-hole pair recombination with the presence of oxygen vacancy and Sn doping in the TiO2 nanotube.
Co-reporter:Haipeng Chu, Xinjuan Liu, Junying Liu, Jinliang Li, Tianyang Wu, Haokun Li, Wenyan Lei, Yan Xu, Likun Pan
Materials Science and Engineering: B 2016 Volume 211() pp:128-134
Publication Date(Web):September 2016
DOI:10.1016/j.mseb.2016.06.010
•Ag2O/N-TiO2 composites were synthesized via a facile precipitation method.•Ag2O/N-TiO2 composites exhibited enhanced photocatalytic activity.•Ag2O acts as co-catalyst to separate the photo-generated electron-hole pairs.A facile precipitation method was developed to synthesize the Ag2O/N-TiO2 composites. Their morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) and phenol under visible light irradiation were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, photoluminescence spectroscopy and UV–vis absorption spectroscopy, respectively. The results show that the Ag2O/N-TiO2 composites exhibit excellent photocatalytic performance. The maximum degradation rates of MB and phenol are about 8.9 and 2.9 times that of pure N-TiO2, respectively. The excellent photocatalytic performance is mainly ascribed to the synergetic effects of Ag2O and N-TiO2 including the increased light absorption and the reduced electron-hole pair recombination in N-TiO2 with the presence of Ag2O.Ag2O/N-TiO2 composites were synthesized via a co-precipitation method for visible light photocatalytic degradation of organic pollutions with excellent photocatalytic activity.
Co-reporter:Xingtao Xu;Jinliang Li;Miao Wang;Yong Liu;Ting Lu ; Likun Pan
ChemElectroChem 2016 Volume 3( Issue 6) pp:993-998
Publication Date(Web):
DOI:10.1002/celc.201600051
Abstract
One of the most challenging issues in developing capacitive deionization (CDI) technologies is the rational design and synthesis of active electrode materials with favorable morphologies and high surface areas. Here, for the first time, shuttle-like porous carbon rods (sPCRs) were prepared through a high temperature pyrolysis step and a subsequent etching step by using rod-like metal–organic frameworks, MIL-88 (Fe), as the precursor. The correlation between the carbonization temperature of sPCRs and their electrosorption performance was investigated, and it was found that, owing to their unique shuttle-like rod structure and high specific surface area, sPCRs obtained at 900 °C exhibit a superior electrosorption capacity of 16.2 mg g−1 with excellent cycling stability, showing that sPCRs could be a promising electrode material for highly efficient CDI.
Co-reporter:Yong Liu, Xingtao Xu, Miao Wang, Ting Lu, Zhuo Sun and Likun Pan
Journal of Materials Chemistry A 2015 vol. 3(Issue 33) pp:17304-17311
Publication Date(Web):20 Jul 2015
DOI:10.1039/C5TA03663A
Nitrogen-doped carbon nanorods (NCNRs) were prepared from naturally based nanocrystalline cellulose through simple freeze drying and subsequent thermal treatment under an ammonia atmosphere at different temperatures. The morphology, structure and electrochemical performance of the NCNRs were characterized using scanning electron microscopy, transmission electron microscopy, nitrogen adsorption–desorption, X-ray photoelectron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy, and their electrosorption performance in NaCl solution was studied. The results show that NCNRs treated at 1000 °C exhibit an extremely high electrosorption capacity of 17.62 mg g−1 when the initial NaCl concentration is 500 mg l−1, which shows great improvement compared with their undoped counterparts. The nitrogen doping proved to be a very effective method for improving the electrosorption performance, and the NCNRs should be very promising candidates as electrode materials for CDI applications.
Co-reporter:Xingtao Xu, Yong Liu, Ting Lu, Zhuo Sun, Daniel H. C. Chua and Likun Pan
Journal of Materials Chemistry A 2015 vol. 3(Issue 25) pp:13418-13425
Publication Date(Web):20 May 2015
DOI:10.1039/C5TA01889G
Capacitive deionization (CDI) is an emerging technology offering a green and efficient route to obtain clean water. Up to now, the key of CDI technology has been focused on the exploration of electrode materials with a rationally designed structure and excellent performance, because the electrosorption performance of the carbon-based electrodes reported to date cannot meet the demands of practical applications of CDI. Herein, novel graphene/carbon nanotubes (CNTs) hybrid sponge (GNS) structures were designed and fabricated via directly freeze-drying graphene oxide/CNTs mixed solution followed by annealing in nitrogen atmosphere. The morphology, structure and electrochemical performance of GNS were characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, nitrogen adsorption–desorption, cyclic voltammetry and electrochemical impedance spectroscopy. The results show that GNS with 20 wt% CNTs has a maximum specific surface area of 498.2 m2 g−1 and a highest specific capacitance of 203.48 F g−1 among all the samples. When used as CDI electrode, it exhibits an ultrahigh electrosorption capacity of 18.7 mg g−1, and, to our knowledge, this value is superior to those of other carbon electrodes reported recently. GNS should be a promising electrode material for high-performance CDI.
Co-reporter:Yong Liu, Ting Lu, Zhuo Sun, Daniel H. C. Chua and Likun Pan
Journal of Materials Chemistry A 2015 vol. 3(Issue 16) pp:8693-8700
Publication Date(Web):11 Mar 2015
DOI:10.1039/C5TA00435G
Ultra-thin carbon nanofiber networks (bc-CNFs) were prepared from natural-based bacterial cellulose pellicle through freeze drying and subsequent carbonization at different temperatures. The morphology, structure and electrochemical performance of the bc-CNFs were characterized by field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, nitrogen adsorption–desorption, Fourier transform infrared spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. Their electrosorption performance in NaCl solution was studied and compared with those of carbon nanotubes (CNTs) and electrospun carbon nanofibers (e-CNFs). The results show that the bc-CNFs treated at 800 °C exhibited excellent desalination performance with an electrosorption capacity of 12.81 mg g−1 in 1000 mg l−1 NaCl solution, much higher than those of the CNTs (3.78 mg g−1) and the e-CNFs (6.56 mg g−1). The excellent performance of the bc-CNFs is ascribed to their high specific surface area, low charge transfer resistance and superior hydrophility.
Co-reporter:Xiaojie Zhang, Wei Qin, Dongsheng Li, Dong Yan, Bingwen Hu, Zhuo Sun and Likun Pan
Chemical Communications 2015 vol. 51(Issue 91) pp:16413-16416
Publication Date(Web):17 Sep 2015
DOI:10.1039/C5CC06924F
Porous CuO/Cu2O composite hollow octahedrons were synthesized simply by annealing Cu-based metal–organic framework templates. When evaluated as anode materials for sodium ion batteries, they exhibit a high maximum reversible capacity of 415 mA h g−1 after 50 cycles at 50 mA g−1 with excellent cycling stability and good rate capability.
Co-reporter:Dong Yan, Caiyan Yu, Ying Bai, Weifeng Zhang, Taiqiang Chen, Bingwen Hu, Zhuo Sun and Likun Pan
Chemical Communications 2015 vol. 51(Issue 39) pp:8261-8264
Publication Date(Web):08 Apr 2015
DOI:10.1039/C4CC10020D
Sn-doped TiO2 nanotubes were employed as anodes for sodium ion batteries. The electrodes exhibit a high maximum charge capacity of 257 mA h g−1 after 50 cycles at a current density of 50 mA g−1 with good rate capability and especially excellent cycling stability, mainly due to the increase of electrical conductivity by Sn doping.
Co-reporter:Yong Liu, Xingtao Xu, Miao Wang, Ting Lu, Zhuo Sun and Likun Pan
Chemical Communications 2015 vol. 51(Issue 60) pp:12020-12023
Publication Date(Web):16 Jun 2015
DOI:10.1039/C5CC03999A
Porous carbon polyhedra (PCP) were prepared through direct carbonization of zeolitic imidazolate framework-8 and used as an electrode material for capacitive deionization. The results show that PCP treated at 1200 °C exhibit the highest electrosorption capacity of 13.86 mg g−1 when the initial NaCl concentration is 500 mg l−1, due to their high accessible surface area and low charge transfer resistance.
Co-reporter:Wei Qin, Taiqiang Chen, Likun Pan, Lengyuan Niu, Bingwen Hu, Dongsheng Li, Jinliang Li, Zhuo Sun
Electrochimica Acta 2015 Volume 153() pp:55-61
Publication Date(Web):20 January 2015
DOI:10.1016/j.electacta.2014.11.034
MoS2-reduced graphene oxide (RGO) composites were synthesized via a facile microwave assisted reduction of graphene oxide in MoS2 precursor solution and subsequent annealing in N2/H2 atmosphere at 800 °C for 2 h. Their morphology, structure and electrochemical performance were characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy, N2 adsorption-desorption isotherm, cyclic voltammetry and electrochemical impedance spectroscopy. The MoS2-RGO composites with different RGO loadings were applied as anode materials of sodium ion batteries (SIBs) and they exhibit a maximum reversible specific capacity of about 305 mAh g−1 at a current density of 100 mA g−1 after 50 cycles and excellent rate performance. The results demonstrate that MoS2-RGO could be a potential electrode material for rechargeable SIBs.Figure optionsDownload full-size imageDownload as PowerPoint slide
Co-reporter:Yong Liu, Likun Pan, Taiqiang Chen, Xingtao Xu, Ting Lu, Zhuo Sun, Daniel H.C. Chua
Electrochimica Acta 2015 Volume 151() pp:489-496
Publication Date(Web):1 January 2015
DOI:10.1016/j.electacta.2014.11.086
•Porous carbon spheres were fabricated through a fast microwave-assisted approach.•The capacitive deionization performance of Porous carbon spheres was studied.•Porous carbon spheres exhibit a high NaCl removal with good regeneration ability.Porous carbon spheres (PCSs) were fabricated through a fast microwave-assisted approach using sucrose as the precursor in a microwave system and subsequent thermal treatment at 600, 800 and 1000 °C. The morphology, structure and electrochemical performance of the PCSs were characterized by scanning electron microscopy, Raman spectroscopy, nitrogen adsorption-desorption, cyclic voltammetry and electrochemical impedance spectroscopy. Their electrosorption performance in NaCl solution was studied and compared with activated carbon, carbon nanotubes, reduced graphene and carbon aerogels. The results show that due to their high specific surface area and low charge transfer resistance, PCSs treated at 1000 °C exhibit high electrosorption capacity of 5.81 m g g−1 when the initial solution concentration is 500 mg l−1, which is higher than those of other carbon materials.
Co-reporter:Xinjuan Liu, Haipeng Chu, Jinliang Li, Lengyuan Niu, Can Li, Huili Li, Likun Pan and Chang Q. Sun
Catalysis Science & Technology 2015 vol. 5(Issue 10) pp:4727-4740
Publication Date(Web):10 Jun 2015
DOI:10.1039/C5CY00622H
Semiconductor photocatalysis has attracted tremendous attention due to its potential in environmental remediation, clean energy production and chemical reaction technology. Pursuing high efficiencies is a core task in the field. One of the major factors in photocatalysis is the limited light absorption of photocatalysts in the incident solar spectrum. In this treatise, we will survey recent advancements in light-conversion phosphor-based composites including up-conversion, down-conversion, and long afterglow phosphor-based composites for photocatalysis.
Co-reporter:Xinjuan Liu, Taiqiang Chen, Haipeng Chu, Lengyuan Niu, Zhuo Sun, Likun Pan, Chang Q. Sun
Electrochimica Acta 2015 Volume 166() pp:12-16
Publication Date(Web):1 June 2015
DOI:10.1016/j.electacta.2015.03.081
Fe2O3-reduced graphene oxide (RGO) composites were successfully fabricated via a facile microwave-assisted reduction of graphite oxide in Fe2O3 precursor solution using a microwave system, and investigated as anode material for sodium ion batteries (SIBs). Their morphologies, structures and electrochemical performance were characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The results show that the RGO addition can enhance the electrochemical performance of Fe2O3-RGO composites. Fe2O3-RGO composite with 30 wt.% RGO exhibits a maximum reversible capacity of 289 mA h g−1 at a current density of 50 mA g−1 after 50 cycles and excellent rate performance due to the synergistic effect between Fe2O3 and RGO. The high capacity, good rate capability and excellent cycle performance of Fe2O3-RGO composites enable them a potential electrode material for SIBs.
Co-reporter:Yong Liu, Taiqiang Chen, Ting Lu, Zhuo Sun, Daniel H.C. Chua, Likun Pan
Electrochimica Acta 2015 Volume 158() pp:403-409
Publication Date(Web):10 March 2015
DOI:10.1016/j.electacta.2015.01.179
•N-doped carbon spheres were obtained via microwave synthesis and ammonia treatment.•N doping enhances the specific surface area and facilitates the charge transfer.•The capacitive deionization performance of N-doped carbon spheres was investigated.•N-doped carbon spheres exhibit a high NaCl removal with good regeneration ability.Nitrogen-doped porous carbon spheres (NPCSs) were prepared through a fast microwave-assisted approach using sucrose as the precursor in a microwave system and subsequent thermal treatment in ammonia atmosphere at different temperatures. The morphology, structure and electrochemical performance of the NPCSs were characterized by scanning electron microscopy, nitrogen adsorption-desorption, X-ray photoelectron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy, and their electrosorption performance in NaCl solution was studied. The results show that NPCSs treated at 1000 °C exhibit an extremely high electrosorption capacity of 14.91 m g g−1 when the initial NaCl concentration is 1000 mg l−1, which shows great improvement compared with their undoped counterpart. The nitrogen doping is suggested to be a very effective method to improve the electrosorption performance, and the NPCSs should be a very promising candidate as electrode material for CDI application.
Co-reporter:Xinjuan Liu, Xiaojun Wang, Huili Li, Jinliang Li, Likun Pan, Jing Zhang, Guoquan Min, Zhuo Sun and Changqing Sun
Dalton Transactions 2015 vol. 44(Issue 1) pp:97-103
Publication Date(Web):20 Oct 2014
DOI:10.1039/C4DT01252F
ZnO–NaSrBO3:Tb3+ (ZNT) composites were successfully synthesized via microwave-assisted reaction of the ZnO precursor with a NaSrBO3:Tb3+ suspension using a microwave synthesis system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-vis absorption spectroscopy, fluorescence spectrophotometry and electrochemical impedance spectroscopy, respectively. The results show that the ZNT composites exhibit enhanced photocatalytic activity in the degradation of MB with a maximum degradation rate of 97% under visible light irradiation compared with pure ZnO (12%), which is ascribed to the increased light absorption and the reduction of photoelectron–hole pair recombination in ZnO with the introduction of NaSrBO3:Tb3+, as well as the light down-converting effect of NaSrBO3:Tb3+, which facilitates the self-sensitized degradation of MB.
Co-reporter:Hengchao Sun, Taiqiang Chen, Yong Liu, Xian Hou, Li Zhang, Guang Zhu, Zhuo Sun, Likun Pan
Journal of Colloid and Interface Science 2015 Volume 445() pp:326-329
Publication Date(Web):1 May 2015
DOI:10.1016/j.jcis.2015.01.016
Carbon microspheres (CSs) were successfully fabricated and used as counter electrodes of dye-sensitized solar cells (DSSCs). CSs were obtained through a fast microwave-assisted approach using sucrose as the precursor in a microwave system and subsequent thermal treatment at 600, 800 and 1000 °C. A maximum photovoltaic conversion efficiency of 5.5% is achieved for DSSCs based on the CSs counter electrodes, which is comparable to the cell based on conventional Pt counter electrode at one sun (AM 1.5 G, 100 mW cm−2). The results suggest the CSs to be a potential candidate for counter electrodes of DSSCs.
Co-reporter:Jinliang Li, Xinjuan Liu, Zhuo Sun, Yi Sun, Likun Pan
Journal of Colloid and Interface Science 2015 Volume 452() pp:109-115
Publication Date(Web):15 August 2015
DOI:10.1016/j.jcis.2015.04.026
The yolk–shell structure Bi4−2xMoxO6 (x ⩽ 1) microspheres were successfully synthesized via a simple solvothermal method. The morphology, structure and photocatalytic performances of the samples in the degradation of rhodamine B (RhB) and methyl orange (MO) were characterized by X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV–vis absorption spectroscopy and electrochemical impedance spectra, respectively. The results show that the yolk–shell structure Bi2.38Mo0.81O6 microspheres exhibit the best photocatalytic performance for the degradation of RhB and MO with a degradation rate of 99% and 72% under visible light irradiation.
Co-reporter:Jinliang Li, Xinjuan Liu, Xian Hou, Wei Qin, Zhuo Sun, Likun Pan
Journal of Colloid and Interface Science 2015 Volume 458() pp:235-240
Publication Date(Web):15 November 2015
DOI:10.1016/j.jcis.2015.07.059
Novel reduced graphene oxide (RGO) wrapped Bi2.38Mo0.81O6 (Bi2.38Mo0.81O6@RGO) composites were successfully synthesized via a facile method. The morphology, structure and photocatalytic performance of the composites in the degradation of Rhodamine B (RhB) and phenol were characterized by scanning electron microscopy, X-ray diffraction, nitrogen adsorption–desorption, UV–vis absorption spectroscopy and electrochemical impedance spectra, respectively. The results show that the Bi2.38Mo0.81O6@RGO composites exhibit enhanced photocatalytic performance in the degradation of RhB and phenol with maximum degradation rates of 99% (80 min) and 88% (240 min) under visible light irradiation, respectively. The improved photocatalytic performance is mainly ascribed to the enhanced light absorption and the reduced electron–hole pair recombination with the presence of RGO in the composites.
Co-reporter:Xinjuan Liu, Junying Liu, Haipeng Chu, Jinliang Li, Wei Yu, Guang Zhu, Lengyuan Niu, Zhuo Sun, Likun Pan, Chang Q. Sun
Applied Surface Science 2015 Volume 347() pp:269-274
Publication Date(Web):30 August 2015
DOI:10.1016/j.apsusc.2015.04.096
Highlights
- •
Bi2O3–Ag2O composites were synthesized via a co-precipitation method.
- •
The photocatalytic activity for the degradation of phenol is investigated.
- •
A high degradation rate of 92% for 60 min is achieved under visible light irradiation.
Co-reporter:Yong Liu, Chunyang Nie, Xinjuan Liu, Xingtao Xu, Zhuo Sun and Likun Pan
RSC Advances 2015 vol. 5(Issue 20) pp:15205-15225
Publication Date(Web):15 Jan 2015
DOI:10.1039/C4RA14447C
The last five decades have witnessed the rapid development of capacitive deionization (CDI) as a novel, low-cost and environment-friendly desalination technology. During the CDI process, salt ions are sequestered by the porous electrodes once exposed to an electric field. These electrodes, acting as an ion storage container, play a vital role during desalination. In this review, various carbon-based composite electrode materials, including carbon–carbon composites, carbon–metal oxide composites, carbon–polymer composites and carbon–polymer–metal oxide composites, are systematically presented. Applications of these carbon-based composite materials for the removal of the salt ions from solution are demonstrated and they exhibit improved CDI performances compared with pristine carbon electrodes.
Co-reporter:Yong Liu, Xingtao Xu, Ting Lu, Zhuo Sun, Daniel H. C. Chua and Likun Pan
RSC Advances 2015 vol. 5(Issue 43) pp:34117-34124
Publication Date(Web):08 Apr 2015
DOI:10.1039/C5RA00620A
A nitrogen-doped electrospun reduced graphene oxide–carbon nanofiber composite (NG–CNF) was fabricated via electrospinning by adding graphite oxide into a precursor solution and subsequent thermal treatment under an ammonia atmosphere. The morphology, structure and electrochemical performance of the composite were characterized by scanning electron microscopy, nitrogen adsorption–desorption, cyclic voltammetry and electrochemical impedance spectroscopy, and their capacitive and electrosorption performances in NaCl solution were studied. The NG–CNF composite electrode shows excellent specific capacitance (337.85 F g−1) and electrosorption capacity (3.91 mg g−1), much higher than those of pure carbon nanofibers (171.28 F g−1 and 3.13 mg g−1) and the reduced graphene oxide–carbon nanofiber composite (264.32 F g−1 and 3.60 mg g−1). The enhanced performance of the NG–CNF is ascribed to the nitrogen doping and the formation of an effective “plane-to-line” conducting network in the composite, which facilitates the electron transfer and ion transport as well as increases the specific surface area.
Co-reporter:Jinliang Li, Xinjuan Liu, Xianqing Piao, Zhuo Sun and Likun Pan
RSC Advances 2015 vol. 5(Issue 21) pp:16592-16597
Publication Date(Web):30 Jan 2015
DOI:10.1039/C4RA16777E
Carbon sphere (CS)@Bi2MoO6 core–shell structure (CS@BMO) composites were successfully synthesized via a solvothermal reaction of CSs and Bi2MoO6 precursors in the mixed solution of ethylene glycol and ethanol. The morphology, structure and photocatalytic performance of the composites in the degradation of Rhodamine B (RhB) were characterized by scanning electron microscopy, X-ray diffraction, UV-vis absorption spectroscopy, electrochemical impedance spectra and nitrogen adsorption–desorption, respectively. The results show that the CS@BMO composites exhibit enhanced photocatalytic performance for degradation of RhB with a maximum degradation rate of 95% under visible light irradiation compared with the pure Bi2MoO6. The improved photocatalytic performance is ascribed to the enhanced specific surface area and light absorption as well as the reduced electron–hole pair recombination with the presence of CSs in the composites.
Co-reporter:Jinliang Li, Xinjuan Liu, Zhuo Sun, Likun Pan
Ceramics International 2015 Volume 41(Issue 7) pp:8592-8598
Publication Date(Web):August 2015
DOI:10.1016/j.ceramint.2015.03.068
Mesoporous yolk-shell structure Bi2MoO6 (BMO-YS) microspheres were successfully synthesized via a facile solvothermal route in Bi2MoO6 precursor solution. The morphology, structure and photocatalytic performance of the BMO-YS in the degradation of Rhodamine B (RhB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, nitrogen adsorption–desorption, UV–vis absorption spectroscopy and electrochemical impedance spectra, respectively. The as-prepared BMO-YS mainly consists of microspheres with diameters of about 1.5 μm. The photocatalytic studies reveal that the BMO-YS not only exhibits optimum photocatalytic performance, which may be attributed to the excellent charge separation characteristics and the enhanced light absorption offered by its unique yolk-shell structure, but also possesses excellent recyclability for photocatalysis.
Co-reporter:Yong Liu, Likun Pan, Xingtao Xu, Ting Lu, Zhuo Sun and Daniel H. C. Chua
Journal of Materials Chemistry A 2014 vol. 2(Issue 48) pp:20966-20972
Publication Date(Web):28 Oct 2014
DOI:10.1039/C4TA04578E
Carbon nanorods (CNRs) were fabricated from natural based nanocrystalline cellulose through a simple thermal treatment at 800, 1000 and 1200 °C. The morphology, structure and electrochemical performance of CNRs were characterized by atomic force microscopy, Raman spectroscopy, nitrogen adsorption–desorption, cyclic voltammetry and electrochemical impedance spectroscopy. Their electrosorption performance in NaCl solution was studied. The results show that CNRs treated at 1200 °C exhibit the highest specific capacitance of 264.19 F g−1 and electrosorption capacity of 15.12 mg g−1 with the initial NaCl concentration of 500 mg l−1, due to their high specific surface area and low charge transfer resistance.
Co-reporter:Taiqiang Chen, Yong Liu, Likun Pan, Ting Lu, Yefeng Yao, Zhuo Sun, Daniel H. C. Chua and Qun Chen
Journal of Materials Chemistry A 2014 vol. 2(Issue 12) pp:4117-4121
Publication Date(Web):10 Jan 2014
DOI:10.1039/C3TA14806H
A simple and scalable electrospinning process followed by thermal treatment was used to fabricate carbon nanofibers (CFs). The as-prepared CFs were investigated as anode materials for sodium ion batteries (SIBs). Remarkably, due to their weakly ordered turbostratic structure and a large interlayer spacing between graphene sheets, the CFs exhibit a dominant adsorption/insertion sodium storage mechanism that shows high reversibility. As a result, the CFs show excellent electrochemical performance, especially cycle stability (97.7% capacity retention ratio over 200 cycles). Reversible capacities of 233 and 82 mA h g−1 are obtained for the CFs at a current density of 0.05 A g−1 and even a high current density of 2 A g−1, respectively. The excellent cycle performance, high capacity and good rate capability make the CFs promising candidates for practical SIBs.
Co-reporter:Taiqiang Chen, Likun Pan, Ting Lu, Conglong Fu, Daniel H. C. Chua and Zhuo Sun
Journal of Materials Chemistry A 2014 vol. 2(Issue 5) pp:1263-1267
Publication Date(Web):11 Nov 2013
DOI:10.1039/C3TA14037G
A fast microwave-assisted approach was developed to fabricate carbon microspheres (CSs) using sucrose as the precursor in a microwave system. After thermal treatment at 300, 500, 700 and 1000 °C, the CSs were used as anode materials for sodium ion batteries (SIBs). The results show that CSs treated at 500 °C exhibit a maximum capacity of 183 mA h g−1 at a current density of 30 mA g−1 after 50 cycles, and even at a high current density of 1000 mA g−1 a capacity of 83 mA h g−1 is maintained. The high capacity, good cycling stability and excellent rate performance of CSs, due to their unique spherical structure, make them a promising candidate for anode materials for SIBs.
Co-reporter:Taiqiang Chen, Likun Pan, T. A. J. Loh, D. H. C. Chua, Yefeng Yao, Qun Chen, Dongsheng Li, Wei Qin and Zhuo Sun
Dalton Transactions 2014 vol. 43(Issue 40) pp:14931-14935
Publication Date(Web):05 Jun 2014
DOI:10.1039/C4DT01223B
Nitrogen-doped carbon microspheres (NCSs) were fabricated via a simple, fast and energy-saving microwave-assisted method followed by thermal treatment under an ammonia atmosphere. NCSs thermally treated at different temperatures were investigated as anode materials for lithium ion batteries (LIBs). The results show that NCSs treated at 900 °C exhibit a maximum reversible capacity of 816 mA h g−1 at a current density of 50 mA g−1 and preserve a capacity of 660 mA h g−1 after 50 cycles, and even at a high current density of 1000 mA g−1, a capacity of 255 mA h g−1 is maintained. The excellent electrochemical performance of NCSs is due to their porous structure and nitrogen-doping. The present NCSs should be promising low-cost anode materials with a high capacity and good cycle stability for LIBs.
Co-reporter:Hengchao Sun, Likun Pan, Guang Zhu, Xianqing Piao, Li Zhang and Zhuo Sun
Dalton Transactions 2014 vol. 43(Issue 40) pp:14936-14941
Publication Date(Web):31 Jul 2014
DOI:10.1039/C4DT01276C
Long afterglow Sr4Al14O25:Eu,Dy phosphors were introduced into the TiO2 photoanode of CdS quantum dot-sensitized solar cells (QDSSCs) as both a scattering and down converting layer, and the photovoltaic performances of the cells were investigated. The results show that the cell with Sr4Al14O25:Eu,Dy achieves a power conversion efficiency of 1.40%, which is an increase of 38% compared to the cell without Sr4Al14O25:Eu,Dy (1.02%). The performance improvement is attributed to enhanced light harvesting via improved light absorption and scattering processes. After a single sun illumination for 1 min and subsequent removal of the light source, the cell with Sr4Al14O25:Eu,Dy could be driven even in the dark by the long persistent light from Sr4Al14O25:Eu,Dy.
Co-reporter:Jinliang Li, Xinjuan Liu, Likun Pan, Wei Qin and Zhuo Sun
RSC Advances 2014 vol. 4(Issue 107) pp:62387-62392
Publication Date(Web):13 Nov 2014
DOI:10.1039/C4RA09830G
Bi/Bi2MoO6 hollow microsphere (BMO-HMS) composites were successfully synthesized via a microwave-assisted reaction of a Bi2MoO6 precursor in an ethylene glycol solution using a microwave synthesis system and subsequent annealing in a nitrogen atmosphere. The morphology, structure and photocatalytic performance of the composites in the degradation of Rhodamine B (RhB) were characterized by scanning electron microscopy, X-ray diffraction, electrochemical impedance spectra, UV-vis absorption spectroscopy, Raman spectroscopy and nitrogen adsorption–desorption, respectively. The results show that the BMO-HMS composites exhibit enhanced photocatalytic performance in the degradation of RhB with a maximum degradation rate of 91% under visible light irradiation compared with the pure Bi2MoO6. The improved photocatalytic performance is ascribed to the enhanced light absorption and the reduced electron–hole pair recombination with the presence of Bi in the composites.
Co-reporter:Wei Yu, Xinjuan Liu, Likun Pan, Jinliang Li, Junying Liu, Jing Zhang, Ping Li, Chen Chen, Zhuo Sun
Applied Surface Science 2014 Volume 319() pp:107-112
Publication Date(Web):15 November 2014
DOI:10.1016/j.apsusc.2014.07.038
Highlights
- •
F-doped TiO2 are synthesized using a modified sol–gel method.
- •
The photocatalytic degradation of methylene blue by F-doped TiO2 is investigated.
- •
A high methylene blue degradation rate of 91% is achieved under visible light irradiation.
Co-reporter:Jinliang Li, Xinjuan Liu, Likun Pan, Wei Qin, Taiqiang Chen and Zhuo Sun
RSC Advances 2014 vol. 4(Issue 19) pp:9647-9651
Publication Date(Web):28 Jan 2014
DOI:10.1039/C3RA46956E
MoS2–reduced graphene oxide (RGO) composites were successfully synthesized via microwave-assisted reduction of graphite oxide in a MoS2 precursor aqueous solution using a microwave system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, X-ray diffraction, electrochemical impedance spectra and UV-vis absorption spectroscopy, respectively. The results show that the MoS2–RGO composites exhibit enhanced photocatalytic performance in the degradation of MB with a maximum degradation rate of 99% under visible light irradiation for 60 min. This excellent photocatalytic activity is due to the contribution from the reduced electron–hole pair recombination, the enhanced light absorption and the increased dye adsorptivity with the introduction of RGO in the composite.
Co-reporter:Junying Liu, Xinjuan Liu, Jinliang Li, Likun Pan and Zhuo Sun
RSC Advances 2014 vol. 4(Issue 73) pp:38594-38598
Publication Date(Web):19 Aug 2014
DOI:10.1039/C4RA05389C
Bi2O3/F–TiO2 composites were successfully synthesized via an aqueous precipitation method. Their morphologies, structures and photocatalytic performance in the degradation of methyl orange (MO) were characterized by scanning electron microscopy, X-ray diffraction, UV-vis absorption spectroscopy and photoluminescence spectroscopy. The results show that the Bi2O3/F–TiO2 composites exhibit enhanced photocatalytic performance in the degradation of MO with a maximum degradation rate of 95% under visible light irradiation for 180 min, which is mainly ascribed to the increase in light adsorption and the reduction in electron–hole pair recombination in Bi2O3 with the introduction of F–TiO2.
Co-reporter:Hengchao Sun, Likun Pan, Xianqing Piao and Zhuo Sun
Journal of Materials Chemistry A 2013 vol. 1(Issue 21) pp:6388-6392
Publication Date(Web):20 Mar 2013
DOI:10.1039/C3TA10596B
An efficient bifunctional structured layer composed of long afterglow SrAl2O4:Eu,Dy phosphors on top of a transparent layer of nanocrystalline TiO2 was fabricated for use in CdS quantum dot-sensitized solar cells (QDSSCs). The introduction of SrAl2O4:Eu,Dy increases the photocurrent of the QDSSCs mainly due to enhanced light harvesting abilities via improved light absorption and scattering. Under one sun illumination (AM 1.5G, 100 mW cm−2), cells containing SrAl2O4:Eu,Dy show a marked improvement in their conversion efficiency (1.24%) compared with cells without SrAl2O4:Eu,Dy (0.98%). After one sun illumination for 1 min, after which the light source was turned off, cells containing SrAl2O4:Eu,Dy show an efficiency of 0.07% under dark conditions due to the irradiation by the long persistent light from SrAl2O4:Eu,Dy. The present strategy should provide a possibility to fulfil the operation of solar cells even in the dark.
Co-reporter:Likun Pan, Xinjuan Liu, Zhuo Sun and Chang Q. Sun
Journal of Materials Chemistry A 2013 vol. 1(Issue 29) pp:8299-8326
Publication Date(Web):03 May 2013
DOI:10.1039/C3TA10981J
Nanostructured photocatalysts have attracted considerable interest due to their wide range of applications in processes such as organic pollutant degradation, heavy metal reduction, air and water purification, hydrogen production, etc. Pursuing high catalytic efficiency is the foremost goal in the field. One of the current key issues is to search for suitable photocatalysts to enhance light harvesting in the UV or visible light region. In this treatise, the microwave-assisted solution-phase synthesis of various nanomaterials including semiconductor oxides and sulfides, Bi-based oxides, as well as nanocomposites including carbon nanotube-based and graphene-based composites is systematically presented with demonstrations of the advantages of the microwave-assisted process over traditional synthesis methods including solid state or vapor reactions and hydrothermal or solvothermal processes. Application of these nanomaterials as photocatalysts for the degradation of pollutants in water or air, removal of Cr(VI) as well as hydrogen evolution is also demonstrated, showing the improved photocatalytic activities compared with the ones synthesized via traditional methods.
Co-reporter:Likun Pan, Shiqing Xu, Xinjuan Liu, Wei Qin, Zhuo Sun, Weitao Zheng, Chang Q. Sun
Surface Science Reports 2013 Volume 68(3–4) pp:418-445
Publication Date(Web):November–December 2013
DOI:10.1016/j.surfrep.2013.10.001
Nanoscaled or porous silicon (p-Si) with and without surface passivation exhibits unusually tunable properties that its parent bulk does never show. Such property tunability amplifies the applicability of Si in the concurrent and upcoming technologies. However, consistent understanding of the fundamental nature of nanoscaled Si remains a high challenge. This article aims to address the recent progress in this regard with focus on reconciling the tunable dielectric, electronic, phononic, and photonic properties of p-Si in terms of skin dominance. We show that the skin-depth bond contraction, local quantum entrapment, and electron localization is responsible for the size-induced property tunability. The shorter and stronger bonds between undercoordinated skin atoms result in the local densification and quantum entrapment of the binding energy and the bonding electrons, which in turn polarizes the dangling bond electrons. Such local entrapment modifies the Hamiltonian and associated properties such as the band gap, core level shift, Stokes shift (electron–phonon interaction), phonon and dielectric relaxation. Therefore, given the known trend of one property change, one is expected to be able to predict the variation of the rest based on the notations of the bond order–length–strength correlation and local bond average approach (BOLS-LBA). Furthermore, skin bond reformation due to Al, Cu, and Ti metallization and O and F passivation adds another freedom to enhance or attenuate the size effect. The developed formulations, spectral analytical methods, and importantly, the established database and knowledge could be of use in engineering p-Si and beyond for desired functions.
Co-reporter:Xinjuan Liu, Likun Pan, Taiqiang Chen, Jinliang Li, Kai Yu, Zhuo Sun and Changqing Sun
Catalysis Science & Technology 2013 vol. 3(Issue 7) pp:1805-1809
Publication Date(Web):26 Mar 2013
DOI:10.1039/C3CY00013C
SnO2 quantum dots (QDs) were successfully synthesized via a microwave-assisted reaction of a SnO2 precursor in an aqueous solution using a microwave system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, UV-vis absorption/reflectance spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the SnO2 QDs synthesized at a pH value of 5 exhibit an optimal photocatalytic performance with a MB degradation rate of 90% at 240 min under visible light irradiation due to their easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.
Co-reporter:Xinjuan Liu, Likun Pan, Jinliang Li, Kai Yu, Zhuo Sun, Chang Q. Sun
Journal of Colloid and Interface Science 2013 Volume 404() pp:150-154
Publication Date(Web):15 August 2013
DOI:10.1016/j.jcis.2013.04.047
•ZnO–Y2O2S:Eu3+ composites are synthesized by microwave-assisted reaction.•The visible light degradation of MB, RhB, and MO by the composites is investigated.•Down-converting Y2O2S:Eu3+ facilitates the self-sensitized destruction of MB.•Higher performance enhancement in degradation of MB than RhB and MO is achieved.One-step synthesis of ZnO–Y2O2S:Eu3+ (ZYE) composites were carried out using a microwave-assisted reaction of the ZnO precursor with a Y2O2S:Eu3+ suspension using a microwave synthesis system. The photocatalytic performance in the degradation of methylene blue (MB), rhodamine B (RhB), and methyl orange (MO) was investigated. The results show that Y2O2S:Eu3+ phosphors play an important role in the enhancement of visible light photocatalysis and ZYE composites exhibit much higher enhancement of visible light photocatalytic performance in the degradation of MB than RhB and MO mainly due to the light down-converting effect of Y2O2S:Eu3+, which facilitates the self-sensitized destruction of MB.Graphical abstract
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Zhuo Sun, Chang Q. Sun
Journal of Colloid and Interface Science 2013 Volume 408() pp:145-150
Publication Date(Web):15 October 2013
DOI:10.1016/j.jcis.2013.07.045
•Bi2O3–RGO composite is synthesized by microwave-assisted reaction.•The photocatalytic degradation of MO and MB by Bi2O3–RGO is investigated.•High MO and MB degradation rates are achieved under visible light irradiation.Bi2O3-reduced graphene oxide (RGO) composites were successfully synthesized via microwave-assisted reduction of graphite oxide in Bi2O3 precursor solution using a microwave system. Their morphologies, structures, and photocatalytic performance in the degradation of methylene blue (MB) and methyl orange (MO) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectroscopy, UV–vis absorption spectroscopy, and electrochemical impedance spectroscopy, respectively. The results show that the RGO addition can enhance the photocatalytic performance of Bi2O3–RGO composites. Bi2O3–RGO composite with 2 wt.% RGO achieves maximum MO and MB degradation rates of 93% and 96% at 240 min under visible light irradiation, respectively, much higher than those for the pure Bi2O3 (78% and 76%). The enhanced photocatalytic performance is ascribed to the increased light adsorption and the reduction in electron–hole pair recombination in Bi2O3 with the introduction of RGO.Graphical abstract
Co-reporter:Yong Liu, Likun Pan, Xingtao Xu, Ting Lu and Zhuo Sun
RSC Advances 2013 vol. 3(Issue 38) pp:16932-16935
Publication Date(Web):19 Jul 2013
DOI:10.1039/C3RA42961J
Carbon nanotube (CNT) film electrodes were fabricated on the graphite substrate using the screen printing method and the electrosorption of LiCl in water, methanol, ethanol and N,N-dimethylformamide (DMF) by CNT electrodes was studied. The results show that the solvent plays an important role in the removal by electrosorption of lithium ions by CNT electrodes and the electrosorption capacities for LiCl in water, methanol, ethanol and DMF solvents are 1.55, 2.13, 1.25, and 2.88 mg g−1, respectively. Such a significant difference is related to the characteristics of the solvent, such as the surface tension, viscosity and affinity to CNTs, which affect the ion penetration inside the porous CNT electrodes.
Co-reporter:Taiqiang Chen, Likun Pan, Xinjuan Liu, Zhuo Sun
Materials Chemistry and Physics 2013 Volume 142(Issue 1) pp:345-349
Publication Date(Web):15 October 2013
DOI:10.1016/j.matchemphys.2013.07.027
•Three carbon materials were used as additives in the electrodes of Li ion battery.•The electrochemical performances of the electrodes were comparatively investigated.•The carbon additives have a significant impact on the electrode performance.•RGO additive acts as a bridge to form a “plane-to-point” conducting network.•The electrode with RGO exhibits better performance than those with other additives.Three nanocarbon materials (0 D acetylene black (AB), 1 D carbon nanotubes (CNTs) and 2 D reduced graphene oxide (RGO)) were used as conductive additives (CAs) in the mesocarbon microbead anodes for lithium ion batteries. The electrochemical performances of the electrodes were investigated. The results show that the CAs have a significant impact on the electrode performance because they can influence the electron conduction and lithium ion transportation within the electrode. The electrode with RGO achieves a maximum capacity of 387 mAh g−1 after 50 cycles at a current density of 50 mA g−1, much higher than those of the electrodes with AB (334 mAh g−1) and CNTs (319 mAh g−1). The improvement should be mainly ascribed to the “plane-to-point” conducting network formed in the electrode with 2 D RGO which can favor the electron conduction and enhance the lithium ion transportation.
Co-reporter:Chunyang Nie, Dong Liu, Likun Pan, Yong Liu, Zhuo Sun, Jun Shen
Solid State Ionics 2013 Volumes 247–248() pp:66-70
Publication Date(Web):1 October 2013
DOI:10.1016/j.ssi.2013.06.003
•Carbon aerogels/reduced graphene oxide (CAs/RGO) electrodes were fabricated.•RGO acts as a bridge to form a “plane-to-point” (RGO-to-CAs) conducting network.•The electrodes exhibit better capacitive performance compared to pure CAs and RGO.In this paper, carbon aerogels (CAs)/reduced graphene oxide (RGO) composite films were fabricated and used as electrodes for supercapacitors. The electrochemical performances of the composite electrodes with different RGO content were evaluated through cyclic voltammetry, electrochemical impedance spectrometry and chronopotentiometry tests. The results show that the incorporation of RGO into CAs can improve the capacitive performance of the composite electrodes due to a synergistic effect between them. Compared with pure CAs and RGO, CAs/RGO composite with 90:10 weight ratio of CAs to RGO exhibits a maximum specific capacitance of 157 F/g, indicating that CAs/RGO composite should be a promising candidate as electrode material for supercapacitors.
Co-reporter:Guang Zhu, Likun Pan, Jie Yang, Xinjuan Liu, Hengchao Sun and Zhuo Sun
Journal of Materials Chemistry A 2012 vol. 22(Issue 46) pp:24326-24329
Publication Date(Web):09 Jul 2012
DOI:10.1039/C2JM33219A
Nest-shaped TiO2 (NS-TiO2) structures were fabricated by an electrospinning technique and used as an effective scattering layer on the top of TiO2 nano-particle electrodes in dye sensitized solar cells (DSSCs). The NS-TiO2 scattering layer enhanced the photocurrent of DSSCs due to the enhanced light harvesting via the improved light scattering and lower electron transfer resistance. Under one sun illumination (AM 1.5G, 100 mW cm−2), a high efficiency of 8.02% was achieved for the cell with a NS-TiO2 scattering layer, which was an increase of 7.1% compared to the cell without a scattering layer (7.49%).
Co-reporter:Haibo Li, Likun Pan, Chunyang Nie, Yong Liu and Zhuo Sun
Journal of Materials Chemistry A 2012 vol. 22(Issue 31) pp:15556-15561
Publication Date(Web):11 Jun 2012
DOI:10.1039/C2JM32207B
In this paper, reduced graphene oxide (RGO) and activated carbon (AC) composites (GAC) have been synthesized by a facile chemical method for the capacitive removal of salt ions from brackish water. The as-prepared composites have been characterized by scanning electron microscopy, N2 adsorption–desorption and cyclic voltammetry. The GAC composite with 20 wt% graphene (GAC-20) exhibits the best electrochemical performance among all the samples, with a specific capacitance of 181 F g−1. The electrosorption capacity of the GAC-20 electrode is found to be much higher than that of the AC electrode, indicating that RGO can serve as a flexible bridge to form a “plane-to-point” (RGO-to-AC) conducting network, which is beneficial for decreasing the aggregation of AC particles, and improves the electron transfer within the composite electrode. GAC composite should be a promising candidate as an electrode material for capacitive deionization (CDI) applications.
Co-reporter:Xinjuan Liu, Xiaojun Wang, Huili Li, Likun Pan, Tian Lv, Zhuo Sun and Changqing Sun
Journal of Materials Chemistry A 2012 vol. 22(Issue 32) pp:16293-16298
Publication Date(Web):25 Jun 2012
DOI:10.1039/C2JM33008C
ZnO–Y3Al5O12:Ce3+ composites were successfully synthesized via a microwave-assisted reaction of the ZnO precursor with a Y3Al5O12:Ce3+ suspension using a microwave synthesis system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectroscopy, fluorescence spectrophotometer, and UV-vis absorption spectrophotometer. The results show that the introduction of Y3Al5O12:Ce3+ can enhance the photocatalytic performance of ZnO with a maximum MB degradation rate of 93% under visible light irradiation compared with pure ZnO (13%) mainly due to the light down-converting effect of Y3Al5O12:Ce3+, which facilitates the self-sensitized destruction of MB.
Co-reporter:Guang Zhu, Xiaojun Wang, Huili Li, Likun Pan, Hengchao Sun, Xinjuan Liu, Tian Lv and Zhuo Sun
Chemical Communications 2012 vol. 48(Issue 7) pp:958-960
Publication Date(Web):24 Nov 2011
DOI:10.1039/C1CC16089C
Y3Al5O12:Ce phosphors have been prepared and used as an effective scattering layer on top of a transparent layer of nanocrystalline TiO2 for dye sensitized solar cells (DSSCs). The Y3Al5O12:Ce scattering layer increases the photocurrent of DSSCs due to the enhanced light harvesting mainly via the improved light absorption and scattering. Under one sun illumination (AM 1.5G, 100 mW cm−2), a high efficiency of 7.91% was achieved for the cell with a Y3Al5O12:Ce scattering layer, which is an increase of 13.5% compared to the cell without a scattering layer (6.97%).
Co-reporter:Tian Lv, Likun Pan, Xinjuan Liu, Ting Lu, Guang Zhu, Zhuo Sun and Chang Q. Sun
Catalysis Science & Technology 2012 vol. 2(Issue 4) pp:754-758
Publication Date(Web):09 Dec 2011
DOI:10.1039/C2CY00452F
One-step synthesis of CdS–TiO2–chemically reduced graphene oxide (RGO) composites was carried out using microwave-assisted reduction of graphite oxide in CdS precursor solution with TiO2 suspension. The photocatalytic performance of CdS–TiO2–RGO composites in degradation of methyl orange was examined. Results show that the RGO addition could enhance the photocatalytic performance of CdS–TiO2 composites with maximum degradation efficiency of 99.5% under visible light irradiation as compared with the pure TiO2 (43%) and CdS–TiO2 (79.9%) composites due to the increase of specific surface area for more adsorbed MO and the reduction of electron–hole pair recombination with the introduction of RGO.
Co-reporter:Tian Lv, Likun Pan, Xinjuan Liu and Zhuo Sun
Catalysis Science & Technology 2012 vol. 2(Issue 11) pp:2297-2301
Publication Date(Web):01 Jun 2012
DOI:10.1039/C2CY20023F
ZnO–reduced graphene oxide (RGO)–carbon nanotube (CNT) composites were successfully synthesized via microwave-assisted reduction of a graphite oxide dispersion in zinc nitrate solution with a CNT suspension. Their photocatalytic performance in the degradation of methylene blue was investigated and the results show that the CNTs play an important role in the enhancement of the photocatalytic performance and the ZnO–RGO–CNT composite with 3.9 wt% CNTs achieves a maximum degradation efficiency of 96% under UV light irradiation for 260 min as compared with ZnO–RGO (88%) due to the increased light absorption and the reduced charge recombination with the introduction of CNTs.
Co-reporter:Tian Lv, Likun Pan, Xinjuan Liu, Zhuo Sun
Electrochimica Acta 2012 Volume 83() pp:216-220
Publication Date(Web):30 November 2012
DOI:10.1016/j.electacta.2012.08.018
CdS–TiO2–Au composites were synthesized via microwave-assisted reaction of CdS precursor and chloroaurate solution with TiO2 suspension using a microwave system. The photocatalytic performance of CdS–TiO2–Au composites in degradation of methyl orange was investigated. The results show that CdS–TiO2–Au composites exhibit an enhanced photocatalytic performance with maximum degradation rate of 98% under visible light irradiation as compared with pure TiO2 (43%) and CdS–TiO2 (80%) composite due to the increased light absorption intensity and the reduction of electron–hole pair recombination with the introduction of Au.
Co-reporter:Chunyang Nie, Likun Pan, Haibo Li, Taiqiang Chen, Ting Lu, Zhuo Sun
Journal of Electroanalytical Chemistry 2012 Volume 666() pp:85-88
Publication Date(Web):1 February 2012
DOI:10.1016/j.jelechem.2011.12.006
Multi-walled carbon nanotubes (CNTs) films have been successfully fabricated by electrophoretic deposition technique and used as electrodes for capacitive deionization (CDI). The as-deposited CNTs electrode exhibits a comparable electrosorption capacity in NaCl solution to other conventional carbon electrodes. The results suggest that electrophoretic deposition has much potential for the facile and controllable fabrication of CDI electrodes.Highlights► Carbon nanotubes films with different thickness are fabricated by electrophoretic deposition. ► The method allows a facile and controllable deposition of films for capacitive deionization. ► A high electrosorption capacity comparable to those of conventional electrodes is achieved.
Co-reporter:Taiqiang Chen, Likun Pan, Xinjiuan Liu, Kai Yu and Zhuo Sun
RSC Advances 2012 vol. 2(Issue 31) pp:11719-11724
Publication Date(Web):03 Oct 2012
DOI:10.1039/C2RA21740F
A facile one-step microwave-assisted method was developed to fabricate SnO2–reduced graphene oxide (RGO)–carbon nanotube (CNT) composites. The as-prepared composites were applied as anode materials for lithium ion batteries and it is found that RGO and CNTs play an important role in the enhancement of the electrochemical performance due to a synergistic effect of SnO2, RGO and CNTs, in which RGO sheets support SnO2 nanoparticles and CNTs act as wires conductively connecting the large RGO sheets together. A SnO2–RGO–CNT composite with 60 wt.% SnO2 achieves a maximum capacity of 502 mA h g−1 after 50 cycles at 100 mA g−1 and even at a high current density of 1000 mA g−1, a capacity of 344 mA h g−1 is maintained.
Co-reporter:Tian Lv, Likun Pan, Xinjuan Liu and Zhuo Sun
RSC Advances 2012 vol. 2(Issue 33) pp:12706-12709
Publication Date(Web):24 Oct 2012
DOI:10.1039/C2RA21382F
BiPO4–CdS composites consisting of BiPO4 nanorods and CdS nanoparticles were successfully synthesized via a microwave-assisted reaction. The photocatalytic performance of the BiPO4–CdS composites, with different proportions of CdS, in the degradation of methyl orange under visible light irradiation was investigated. The results show that the BiPO4–CdS composite with 30.1 wt% CdS achieves a better performance with a maximum degradation rate of 98.1% as compared with pure BiPO4 due to the increase of specific surface area for more adsorbed MO, the enhancement of light absorption and the reduction of carrier recombination.
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Zhuo Sun and Changqing Sun
RSC Advances 2012 vol. 2(Issue 9) pp:3823-3827
Publication Date(Web):07 Mar 2012
DOI:10.1039/C2RA01107G
Au/N–TiO2 composites are successfully synthesized via a modified sol–gel method and their photocatalytic performance in reduction of Cr(VI) is investigated. Au/N–TiO2 composites exhibit an enhanced photocatalytic performance in the reduction of Cr(VI) with a maximum reduction rate of 90% under visible light irradiation as compared with pure TiO2 (34%) and N–TiO2 (80%) due to the increase of light absorption intensity and range as well as the reduction of electron–hole pair recombination in TiO2 with the incorporation of N and Au.
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Zhuo Sun, Changqing Sun
Journal of Molecular Catalysis A: Chemical 2012 Volumes 363–364() pp:417-422
Publication Date(Web):November 2012
DOI:10.1016/j.molcata.2012.07.019
ZnO–TiO2–carbon nanotubes (CNTs) composites are successfully synthesized using microwave-assisted reaction of ZnO precursor in TiO2 and CNTs suspension using a microwave synthesis system and they are used as photocatalysts for photocatalytic reduction of Cr(VI). The results show that the CNTs addition could enhance the photocatalytic performance of ZnO–TiO2 composites. The ZnO–TiO2 composites achieve a maximum reduction rate of 90% at 240 min under UV light irradiation, much higher than those for the pure ZnO (58%) and the ZnO–TiO2 (69%). The improvement is ascribed to the increased light absorption intensity and range as well as the reduction of electron–hole pair recombination with the introduction of CNTs.Graphical abstractHighlights► ZnO–TiO2–CNTs composite is synthesized by microwave-assisted reaction. ► The photocatalytic reduction of Cr(VI) by ZnO–TiO2–CNTs is investigated. ► A high Cr(VI) reduction rate of 90% is achieved under UV light irradiation.
Co-reporter:Jie Yang, Likun Pan, Guang Zhu, Xinjuan Liu, Hengchao Sun, Zhuo Sun
Journal of Electroanalytical Chemistry 2012 s 677–680() pp: 101-104
Publication Date(Web):
DOI:10.1016/j.jelechem.2012.05.018
Co-reporter:Guang Zhu; Dr. Likun Pan;Hengchao Sun;Xinjuan Liu;Tian Lv;Ting Lu;Jie Yang ; Dr. Zhuo Sun
ChemPhysChem 2012 Volume 13( Issue 3) pp:769-773
Publication Date(Web):
DOI:10.1002/cphc.201100861
Abstract
A reduced graphene (RG)-Au nanoparticle composite film is successfully fabricated by electrophoretic deposition and used as counter electrode for quantum dot-sensitized solar cells. The RG-Au composite is prepared by one-step microwave-assisted reduction of chloroaurate in alkaline solution with graphite oxide dispersion. Under one sun illumination (AM 1.5 G, 100 mW cm−2), the cell with a RG-Au counter electrode shows an energy conversion efficiency of 1.36 %, which is higher than those of cells employing conventional Pt or Au counter electrodes, due to the superior combination of highly catalytic Au nanoparticles and the conductive graphene network structure.
Co-reporter:Taiqiang Chen, Likun Pan, Kai Yu, Zhuo Sun
Solid State Ionics 2012 Volume 229() pp:9-13
Publication Date(Web):14 December 2012
DOI:10.1016/j.ssi.2012.10.005
Reduced graphene oxide (RGO)–carbon nanotube (CNT) composites were successfully fabricated by microwave-assisted reduction of graphene oxide in CNT suspension using a microwave system and their morphologies, structures and electrochemical performances as negative electrode materials of lithium ion batteries were investigated. The results show that as compared with pure RGO and CNTs, RGO–CNT composites exhibit a better electrochemical activity with a maximum reversible capacity of ~ 300 mA h g− 1 after 50 galvanostatic charge–discharge cycles due to a synergistic effect of RGO and CNTs in which CNTs act as wires conductively connecting the large RGO sheets together. The RGO–CNT composites should provide a potential feasibility for the negative electrode materials of LIBs.Highlights► Reduced graphene oxide–carbon nanotube composites are fabricated. ► The microwave-assisted method allows a safe and rapid synthesis in aqueous media. ► The composites exhibit an improved performance as anodes for lithium ion batteries.
Co-reporter:Guang Zhu, Likun Pan, Ting Lu, Tao Xu and Zhuo Sun
Journal of Materials Chemistry A 2011 vol. 21(Issue 38) pp:14869-14875
Publication Date(Web):19 Aug 2011
DOI:10.1039/C1JM12433A
Reduced graphene (RG)-carbon nanotubes (CNTs) composite films are successfully fabricated by electrophoretic deposition and used as counter electrodes of dye-sensitized solar cells. RG is obtained by microwave-assisted reduction of graphite oxide dispersion in aqueous solution using a microwave synthesis system. By the optimization of CNTs content, photovoltaic conversion efficiency of the cell with RG-CNTs counter electrode reaches a maximum of 6.17% at one sun (AM 1.5 G, 100 mW cm−2) which is comparable to the cell with conventional Pt counter electrode. The results suggest that the RG-CNTs composite films provide a potential feasibility for replacing conventional Pt counter electrodes for DSSCs.
Co-reporter:Guang Zhu, Likun Pan, Tao Xu, Qingfei Zhao, Bin Lu and Zhuo Sun
Nanoscale 2011 vol. 3(Issue 5) pp:2188-2193
Publication Date(Web):30 Mar 2011
DOI:10.1039/C1NR10068H
CdSe
quantum dot (QD ) sensitized TiO2 films have been fabricated using a one-step microwave assisted chemical bath deposition (MACBD) technique and used as photoanodes for quantum dot sensitized solar cells. This technique allows direct and rapid deposition and a good contact between the CdSe and TiO2 films. The photovoltaic performances of the cells with CdSe deposited at different times are investigated. The results show that cells based on MACBD deposited TiO2/CdSe electrodes achieve a maximum short circuit current density of 12.1 mA cm−2 and a power conversion efficiency of 1.75% at one Sun (AM 1.5 G, 100 mW cm−2), which is comparable with those fabricated using conventional techniques.
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Guang Zhu, Zhuo Sun and Changqing Sun
Chemical Communications 2011 vol. 47(Issue 43) pp:11984-11986
Publication Date(Web):30 Sep 2011
DOI:10.1039/C1CC14875C
CdS–reduced graphene oxide (RGO) composites are successfully synthesized via the microwave-assisted reduction of graphite oxide in a CdS precursor solution using a microwave synthesis system. The photocatalytic performances of CdS–RGO composites in the reduction of Cr(VI) are investigated. The results show that CdS–RGO composites exhibit enhanced photocatalytic performance for the reduction of Cr(VI) with a maximum removal rate of 92% under visible light irradiation as compared with pure CdS (79%) due to the increased light absorption intensity and the reduction of electron–hole pair recombination in CdS with the introduction of RGO.
Co-reporter:Guang Zhu, Likun Pan, Tao Xu, and Zhuo Sun
ACS Applied Materials & Interfaces 2011 Volume 3(Issue 8) pp:3146
Publication Date(Web):July 11, 2011
DOI:10.1021/am200648b
A CdS/CdSe quantum-dot (QD)-cosensitized TiO2 film has been fabricated using a microwave-assisted chemical bath deposition technique and used as a photoanode for QD-sensitized solar cells. The technique allows a direct and rapid deposition of QDs and forms a good contact between QDs and TiO2 films. The photovoltaic performance of the as-prepared cell is investigated. The results show that the performance of the CdS/CdSe-cosensitized cell achieves a short-circuit current density of 16.1 mA cm–2 and a power conversion efficiency of 3.06% at one sun (AM 1.5 G, 100 mW cm–2), which is comparable to the one fabricated using conventional successive ionic layer adsorption and reaction technique.Keywords: electrodes; microwave-assisted chemical bath deposition; quantum dots; solar cells; titanium dioxide;
Co-reporter:Guang Zhu, Likun Pan, Tao Xu, and Zhuo Sun
ACS Applied Materials & Interfaces 2011 Volume 3(Issue 5) pp:1472
Publication Date(Web):May 2, 2011
DOI:10.1021/am200520q
Sensitized-type solar cells based on TiO2 photoanodes and CdS quantum dots (QDs) as sensitizers have been studied. CdS QDs are grown on TiO2 films, utilizing one-step microwave assisted chemical bath deposition (MACBD) method. This method allows a facile and rapid deposition and integration between CdS QDs and TiO2 films. The photovoltaic performances of the cells fabricated using CdS precursor solutions with different concentrations are investigated. The results show that the cell based on MACBD deposited TiO2/CdS electrode achieves a maximum short circuit current density of 7.20 mAcm-2 and power conversion efficiency of 1.18 % at one sun (AM 1.5G, 100 mW cm-2), which is comparable to the ones prepared using conventional techniques.Keywords: electrodes; microwave-assisted chemical bath deposition; quantum dots; solar cells; titanium dioxide
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Ting Lu, Guang Zhu, Zhuo Sun and Changqing Sun
Catalysis Science & Technology 2011 vol. 1(Issue 7) pp:1189-1193
Publication Date(Web):11 Jul 2011
DOI:10.1039/C1CY00109D
ZnO–graphene composites are successfully synthesized via microwave-assisted reaction of zinc sulfate in aqueous solution with a graphite oxide dispersion using a microwave synthesis system. Their morphology, structure and photocatalytic performance in reduction of Cr(VI) are characterized by scanning electron microscopy, X-ray diffraction spectroscopy and UV-vis absorption spectrophotometer, respectively. The results show that in the composite the graphene nanosheets are decorated densely by ZnO nanosheets, which display a good combination between graphene and ZnO nanosheets. The ZnO–graphene composite exhibits an enhanced photocatalytic performance in the reduction of Cr(VI) with a removal rate of 98% under UV light irradiation as compared with pure ZnO (58%) due to the increased light absorption intensity and range, as well as the reduction of electron–hole pair recombination with the introduction of graphene.
Co-reporter:Yankun Zhan, Chunyang Nie, Haibo Li, Likun Pan, Zhuo Sun
Electrochimica Acta 2011 Volume 56(Issue 9) pp:3164-3169
Publication Date(Web):30 March 2011
DOI:10.1016/j.electacta.2011.01.059
The composite films of activated carbon fibers (ACFs) and carbon nanofibers (CNFs) are prepared via chemical vapor deposition of CNFs onto ACFs in different times from 0.5 to 2 h and their electrosorption behaviors in NaCl solution are investigated. The morphology, structure, porous and electrochemical properties are characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, N2 adsorption at 77 K, contact angle goniometer and electrochemical workstation, respectively. The results show that CNFs have been hierarchically grown on the surface of ACFs and the as grown ACF/CNF composite films have less defects, higher specific capacitances, more suitable mesoporous structure and more hydrophilic surface than the pristine ACFs, which is beneficial to their electrosorption performance. The ACFs/CNFs with CNFs deposited in 1 h exhibit an optimized NaCl removal ratio of 80%, 55% higher than that of ACFs and the NaCl electrosorption follows a Langmuir isotherm with a maximum electrosorption capacity of 17.19 mg/g.
Co-reporter:Guang Zhu, Likun Pan, Ting Lu, Xinjuan Liu, Tian Lv, Tao Xu, Zhuo Sun
Electrochimica Acta 2011 Volume 56(Issue 27) pp:10288-10291
Publication Date(Web):30 November 2011
DOI:10.1016/j.electacta.2011.09.028
Carbon nanotubes (CNTs) films have been successfully fabricated by electrophoretic deposition (EPD) technique and used as counter electrodes of dye-sensitized solar cells (DSSCs). The CNTs counter electrodes consisting of a large number of bamboo-like structures with defect-rich edge planes exhibit a highly interconnected network structure with high electrical conductivity and good catalytic activity. A high photovoltaic conversion efficiency of 7.03% is achieved for DSSCs based on the CNTs counter electrodes, which is comparable to the cell based on conventional Pt counter electrode at one sun (AM 1.5G, 100 mW cm−2). The results suggest that the present synthetic strategy provides a potential feasibility for the fabrication of low-cost flexible counter electrodes of DSSCs using a facile deposition technique from an environmentally “friendly” solution at low temperature.
Co-reporter:Ting Lu, Likun Pan, Haibo Li, Chunyang Nie, Mingfu Zhu, Zhuo Sun
Journal of Electroanalytical Chemistry 2011 Volume 661(Issue 1) pp:270-273
Publication Date(Web):1 October 2011
DOI:10.1016/j.jelechem.2011.07.042
Reduced graphene oxide (RGO)-carbon nanotubes (CNTs) composite films were successfully fabricated by electrophoretic deposition and used as electrode materials for electrochemical supercapacitors. RGO was obtained by microwave-assisted reduction of graphene oxide dispersion in acidic aqueous solution using a microwave synthesis system. The electrochemical performances of the films were analyzed through cyclic voltammetry and chronopotentiometry tests. The results showed that as compared with pure RGO and CNTs, RGO–CNTs composite with 40% CNTs exhibited an optimal electrochemical capacitance of 87 F/g due to a synergistic effect of RGO and CNTs.Highlights► Reduced graphene oxide–carbon nanotubes films are fabricated by electrophoretic deposition. ► The method allows a rapid, controllable and uniform deposition of films for supercapacitors. ► A high capacitance value with good charging/discharging ability is achieved.
Co-reporter:Guang Zhu, Likun Pan, Tao Xu, Zhuo Sun
Journal of Electroanalytical Chemistry 2011 Volume 659(Issue 2) pp:205-208
Publication Date(Web):15 August 2011
DOI:10.1016/j.jelechem.2011.05.018
A simple, rapid and effective method of microwave assisted chemical bath deposition (MACBD) has been used to deposit CdS quantum dots on the surface of TiO2 film as photoanode of quantum dot-sensitized solar cells. The photovoltaic performance of the as-prepared cell is investigated. The results show that the cell based on MACBD deposited TiO2/CdS electrode achieves an improved short circuit current density of 6.69 mA cm−2 and power conversion efficiency of 1.03% at one sun (AM 1.5G, 100 mW cm−2) as compared with the one employing conventional sequential chemical bath deposition method.Highlights► Solar cells based on CdS quantum dot sensitized TiO2 photoanode are fabricated. ► CdS is deposited on TiO2 films using microwave assisted chemical bath deposition. ► This method offers a simple, rapid and effective deposition of CdS. ► As-prepared cell achieves maximally a power conversion efficiency of 1.03%.
Co-reporter:Ting Lu, Likun Pan, Haibo Li, Guang Zhu, Tian Lv, Xinjuan Liu, Zhuo Sun, Ting Chen, Daniel H.C. Chua
Journal of Alloys and Compounds 2011 Volume 509(Issue 18) pp:5488-5492
Publication Date(Web):5 May 2011
DOI:10.1016/j.jallcom.2011.02.136
Graphene–ZnO nanocomposite was successfully synthesized via microwave-assisted reduction of zinc ions in aqueous solution with graphite oxide dispersion using a microwave synthesis system. The electrochemical performance of the nanocomposite was analyzed through cyclic voltammetry and chronopotentiometry tests. The results showed that as compared with pure graphene, graphene–ZnO composite exhibited an improved electrochemical capacitance of 146 F/g with good reversible charge/discharge behavior.Graphical abstractHighlights► Graphene–ZnO nanocomposite is synthesized by microwave assisted reduction method. ► The method allows a facile, safe and rapid reduction in aqueous media. ► A high capacitance value with good charging/discharging ability is achieved.
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Guang Zhu, Ting Lu, Zhuo Sun and Changqing Sun
RSC Advances 2011 vol. 1(Issue 7) pp:1245-1249
Publication Date(Web):19 Sep 2011
DOI:10.1039/C1RA00298H
TiO2-reduced graphene oxide (RGO) composites are successfully synthesized via the microwave-assisted reduction of graphite oxide in a TiO2 suspension using a microwave synthesis system. Their morphology, structure and photocatalytic performance in the reduction of Cr(VI) are characterized by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction spectroscopy and UV-vis absorption spectrophotometer. The results show that in the composite the RGO nanosheets are densely decorated by TiO2 nanoparticles, which displays a good combination between RGO and TiO2. TiO2–RGO composites exhibit enhanced photocatalytic performance for the reduction of Cr(VI) with a maximum removal rate of 91% under UV light irradiation as compared with pure TiO2 (83%) and commercial TiO2 P25 (70%) due to the increased light absorption intensity and range as well as the reduction of electron-hole pair recombination in TiO2 with the introduction of RGO.
Co-reporter:Haibo Li, Likun Pan, Ting Lu, Yankun Zhan, Chunyang Nie, Zhuo Sun
Journal of Electroanalytical Chemistry 2011 Volume 653(1–2) pp:40-44
Publication Date(Web):1 April 2011
DOI:10.1016/j.jelechem.2011.01.012
This paper presents a comparative study on electrosorptive behavior of commercial single walled and double walled carbon nanotubes (CNTs) and as-prepared graphene as potential electrode materials for capacitive deionization (CDI). Their electrosorptive behaviors are evaluated under the same experimental conditions and described by various adsorption isotherms and kinetics models. It was found that the electrosorptive capacity of CNTs (single walled or double walled)-based CDI is higher than that of graphene-based CDI, which is related to their specific surface area, pore structure and hydrophilic functional groups. Electrosorptive kinetics analysis further confirms that CNTs are more suitable as electrode materials than graphene.Research highlights► Carbon nanotubes and graphene are compared for their electrosorptive behaviors. ► Electrosorptive capacity is related to specific surface area and pore structure. ► Carbon nanotubes are more suitable as electrode materials than graphene.
Co-reporter:Guang Zhu, Tian Lv, Likun Pan, Zhuo Sun, Changqing Sun
Journal of Alloys and Compounds 2011 Volume 509(Issue 2) pp:362-365
Publication Date(Web):12 January 2011
DOI:10.1016/j.jallcom.2010.09.026
Sensitized-type solar cells based on ZnO photoanode and CdS quantum dots (QDs) as sensitizers have been fabricated. Both ZnO films and CdS QDs are prepared using ultrasonic spray pyrolysis (USP) deposition technique. This method allows a facile and rapid deposition and integration between CdS QDs and ZnO films without the need for post thermal treatment. The photovoltaic performances of the cells are investigated. The results show that the performance of the cell based on all USP deposited CdS sensitized ZnO photoanode achieves maximally a short circuit current density of 6.99 mA cm−2 and a power conversion efficiency of 1.54%.Graphical abstractResearch highlights▶ Solar cells based on CdS quantum dot sensitized ZnO photoanode are fabricated. ▶ Both ZnO and CdS are prepared using ultrasonic spray pyrolysis technique. ▶ Good contact is formed between CdS and ZnO to facilitate the electron transfer. ▶ As-prepared cell achieves maximally a power conversion efficiency of 1.54%.
Co-reporter:Guang Zhu, Likun Pan, Tao Xu, Qingfei Zhao, Zhuo Sun
Journal of Alloys and Compounds 2011 Volume 509(Issue 29) pp:7814-7818
Publication Date(Web):21 July 2011
DOI:10.1016/j.jallcom.2011.05.043
Quantum dot sensitized solar cells based on cascade structure of TiO2/ZnO/CdS electrode and polysulfide electrolyte were fabricated. The ZnO layer was deposited on screen-printed TiO2 layer by ultrasonic spray pyrolysis method. The structure, morphology and impedance of TiO2/ZnO film photoanode and the photovoltaic performance of TiO2/ZnO/CdS cell were investigated. It is found that the short circuit current density and conversion efficiency are significantly improved by the introduction of ZnO layer into TiO2/CdS film. A power conversion efficiency of about 1.56% has been obtained for TiO2/ZnO/CdS cell, which is about 57% higher than that for TiO2/CdS cell (0.99%). The formation of an inherent energy barrier between TiO2 and CdS films and the passivation of surface traps on the TiO2 film caused by the introduction of ZnO layer, which reduces the charge recombination and favors the electron transport, should be mainly responsible for the performance enhancement of TiO2/ZnO/CdS cell.Highlights► Solar cells based on a cascade structure of TiO2/ZnO/CdS photoanode are fabricated. ► ZnO is one-step deposited on TiO2 layer by ultrasonic spray pyrolysis technique. ► As-prepared cell achieves a power conversion efficiency of 1.56%.
Co-reporter:Guang Zhu, Tao Xu, Tian Lv, Likun Pan, Qingfei Zhao, Zhuo Sun
Journal of Electroanalytical Chemistry 2011 650(2) pp: 248-251
Publication Date(Web):
DOI:10.1016/j.jelechem.2010.10.011
Co-reporter:Guang Zhu, Zujun Cheng, Tian Lv, Likun Pan, Qingfei Zhao and Zhuo Sun
Nanoscale 2010 vol. 2(Issue 7) pp:1229-1232
Publication Date(Web):20 May 2010
DOI:10.1039/C0NR00087F
Quantum dot-sensitized solar cells based on Zn-doped TiO2 (Zn-TiO2) film photoanode and polysulfide electrolyte were fabricated. Zn-TiO2 nanoparticles were obtained via a hydrothermal method and screen printed on the fluorine-doped tin oxide glass to prepare the photoanode. The structure, morphology and impedance of the Zn-TiO2/CdS film and the photovoltaic performance of the Zn-TiO2/CdS cell were investigated. It was found that the photovoltaic efficiency was improved by 24% when the Zn-TiO2 film was adopted as the photoanode of CdS QDSSCs instead of only the TiO2 layer. The improvement was ascribed to the reduction of electron recombination and the enhancement of electron transport in the TiO2 film by Zn doping.
Co-reporter:Ting Lu, Yanping Zhang, Haibo Li, Likun Pan, Yinlun Li, Zhuo Sun
Electrochimica Acta 2010 Volume 55(Issue 13) pp:4170-4173
Publication Date(Web):1 May 2010
DOI:10.1016/j.electacta.2010.02.095
Graphene, graphene–ZnO and graphene–SnO2 films were successfully synthesized and used as electrode materials for electrochemical supercapacitors, respectively. The screen-printing approach was employed to fabricate graphene film on graphite substrate while the ZnO and SnO2 were deposited on graphene films by ultrasonic spray pyrolysis. The electrochemical performances of these electrodes were comparatively analyzed through electrochemical impedance spectrometry, cyclic voltammetry and chronopotentiometry tests. The results showed that the incorporation of ZnO or SnO2 improved the capacitive performance of graphene electrode. Graphene–ZnO composite electrode exhibited higher capacitance value (61.7 F/g) and maximum power density (4.8 kW/kg) as compared with graphene–SnO2 and pure graphene electrodes.
Co-reporter:Haibo Li, Likun Pan, Yanping Zhang, Linda Zou, Changqing Sun, Yankun Zhan, Zhuo Sun
Chemical Physics Letters 2010 Volume 485(1–3) pp:161-166
Publication Date(Web):18 January 2010
DOI:10.1016/j.cplett.2009.12.031
Abstract
The carbon nanotubes and carbon nanofibers composite films (CNTs–CNFs) were fabricated by chemical vapor deposition. The electrosorption performance of CNTs–CNFs films at different solution temperatures was studied. It is found that the salt removal decreases from 45.4% to 33% due to hydrophobic–hydrophilic transition taking place on the surface of CNTs–CNFs films, when solution temperature ranges from 281 to 295 K. The electrosorption isotherm investigation shows Langmuir isotherm can better describe experimental data. Meanwhile, the kinetics and thermodynamics analyses indicate that the electrosorption of NaCl onto CNTs–CNFs electrodes follows first-order kinetics model and is driven by a physisorption process.
Co-reporter:Haibo Li, Ting Lu, Likun Pan, Yanping Zhang and Zhuo Sun
Journal of Materials Chemistry A 2009 vol. 19(Issue 37) pp:6773-6779
Publication Date(Web):21 Jul 2009
DOI:10.1039/B907703K
Graphene has been synthesized by the modified Hummers method and used as electrosorptive electrodes for capacitive deionization. Batch-mode experiments in NaCl solutions at low voltage (≤2 V) are conducted in a continuously recycling system to investigate the electrosorption performance of graphene. The results show that the graphene exhibits a high electrosorption capacity of 1.85 mg/g. The ion sorption follows a Freundlich isotherm, indicating monolayer adsorption. And the electrosorption of NaCl onto graphene electrodes is driven by a physisorption process by taking into account the thermodynamic parameters.
Co-reporter:Yanping Zhang, Haibo Li, Likun Pan, Ting Lu, Zhuo Sun
Journal of Electroanalytical Chemistry 2009 Volume 634(Issue 1) pp:68-71
Publication Date(Web):1 September 2009
DOI:10.1016/j.jelechem.2009.07.010
Graphene–ZnO composite film was synthesized for its potential application in supercapacitors. Graphene was prepared by a modified Hummers method and hydrazine reduction process, and ZnO was deposited on graphene by ultrasonic spray pyrolysis. The electrochemical characteristics of the film were investigated through electrochemical impedance spectrometry, cyclic voltammetry and chronopotentiometry tests. The results showed that graphene–ZnO composite film exhibited an enhanced capacitive behavior with better reversible charging/discharging ability and higher capacitance values, by comparison to pure graphene or ZnO electrode.
Co-reporter:Likun Pan, Zhuo Sun
Journal of Physics and Chemistry of Solids 2009 Volume 70(Issue 7) pp:1113-1116
Publication Date(Web):July 2009
DOI:10.1016/j.jpcs.2009.06.008
Impedance characterization at different temperatures has been used to investigate the conductive behavior of Poly(3-hexylthiophene) (P3HT), prepared in different solvents, as the semiconductor layer in organic multilayer capacitor. It has been found that the P3HT films using chloroform and toluene solvents exhibit an enhancement in conductivity by heating following an Arrhenius law with an activation energy transition from 0.004 to 0.026 eV and from 0.002 to 0.015 eV at ~313 K, respectively, which originates from band tail hopping that occurs around the Fermi edge. The boiling point of the used solvents can affect P3HT crystallization process, which causes the difference in conduction and activation energy.
Co-reporter:Yanping Zhang, Xiaowei Sun, Likun Pan, Haibo Li, Zhuo Sun, Changqing Sun, Beng Kang Tay
Solid State Ionics 2009 Volume 180(32–35) pp:1525-1528
Publication Date(Web):26 November 2009
DOI:10.1016/j.ssi.2009.10.001
Carbon nanotube (CNT)–zinc oxide (ZnO) nanocomposite and gel poly(vinyl alcohol)–phosphomolybdic acid were employed as the electrode and electrolyte of the experimental supercapacitor cell, respectively. The ZnO nanodots were deposited onto CNT films by ultrasonic spray pyrolysis in different times. The results of electrochemical measurements showed that the electrode with ZnO deposited in 5 min had the optimal capacitive properties among the experimental series, with a lowest interfacial electron transfer resistance, a very high capacitance of 323.9 F/g and good reversibility in the repetitive charge/discharge cycling test.
Co-reporter:Yang Gao, Likun Pan, HaiBo Li, Yanping Zhang, Zhejuan Zhang, Yiwei Chen, Zhuo Sun
Thin Solid Films 2009 Volume 517(Issue 5) pp:1616-1619
Publication Date(Web):1 January 2009
DOI:10.1016/j.tsf.2008.09.065
The cost-effective, large area carbon nanotubes and carbon nanofibres (CNTs–CNFs) composite film was synthesized on graphite substrate by low pressure and low temperature thermal chemical vapor deposition. Cyclic voltammetry and ac impedance spectroscopy were employed to systematically study the electrochemical properties of CNTs–CNFs film. The electrosorption in salt solutions by CNTs–CNFs film electrodes was studied. It is found that electrosorption of CNTs–CNFs film electrodes is mainly due to Coulombic interaction on the electrical double-layer. Several experiments were conducted to study the ion removal capacity and selectivity of CNTs–CNFs film electrodes, showing that multivalent cations were preferentially adsorbed from the aqueous solution. For cations with same charge, the one with smaller hydrated radius would be more effectively removed.
Co-reporter:Xingtao Xu, Miao Wang, Yong Liu, Yanjiang Li, Ting Lu, Likun Pan
Energy Storage Materials (October 2016) Volume 5() pp:132-138
Publication Date(Web):1 October 2016
DOI:10.1016/j.ensm.2016.07.002
Recently utilizing metal-organic frameworks (MOFs) as precursors to prepare porous carbons for supercapacitors application has attracted enormous attention. Unfortunately, such MOFs-derived porous carbons are mostly microporous and of low graphitization degree, which are considered unfavorable for the ion and electron transport. Further efforts need to be made to address this issue. Here we propose a new hybrid carbon nanotubes (CNTs)/nitrogen-doped carbon polyhedra (NCP) structure, which was fabricated via using CNTs as substrate for in situ growth of MOFs, [Zn(2-MeIM)2] (2-MeIM: 2-methylimidazolate, ZIF-8) with a subsequent annealing process. The resultant CNTs/NCP hybrid possesses a high specific surface area of 898.0 m2 g−1 and a nitrogen content of 9.43 wt%. When applied as supercapacitor electrode, it exhibits a maximum specific capacitance of 308.0 F g−1 at a scan rate of 5 mV s−1 in 1 M H2SO4 aqueous electrolyte measured in a three-electrode system, and even at a high scan rate of 200 mV s−1, the capacitance still reaches 200.6 F g−1. Furthermore, the CNTs/NCP-based symmetric supercapacitor exhibits a high energy density of 12.0 W h Kg−1 and good cycle ability. It is believed that CNTs/NCP should be promisingly applicable as a high performance supercapacitor electrode material.Download full-size image
Co-reporter:Xiaojie Zhang, Guang Zhu, Miao Wang, Jiabao Li, Ting Lu, Likun Pan
Carbon (May 2017) Volume 116() pp:
Publication Date(Web):May 2017
DOI:10.1016/j.carbon.2017.02.057
N-doped porous carbon materials (NPCs) were prepared by the carbonization of covalent-organic frameworks as precursors and used as anodes for lithium and sodium ion batteries (LIBs and SIBs) for the first time. The morphology, structure and electrochemical performance were characterized and evaluated by field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, X-ray diffraction, nitrogen adsorption and desorption isotherms, galvanostatic charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The NPCs not only show high maximum reversible charge capacities of 488 mAh g−1 at 100 mA g−1 (LIBs) and 237.7 mAh g−1 at 50 mA g−1 (SIBs) after 100 cycles, but also deliver high reversible charge capacities of 143 mAh g−1 at 5 A g−1 (LIBs) and 88.8 mAh g−1 at 2.5 A g−1 (SIBs) and excellent rate performance. Moreover, superior long-life cycling stability is observed for 5000 cycles even at a very high current density of 5 A g−1 for LIBs and 2.5 A g−1 for SIBs. The excellent electrochemical performance of NPCs with superior reversible capacity, good rate performance, and long-life cycling stability is attributed to their N doping, high specific surface area and porous structure with large interlayer distance.
Co-reporter:Xiaojie Zhang, Conglong Fu, Jinliang Li, Chuang Yao, Ting Lu, Likun Pan
Ceramics International (March 2017) Volume 43(Issue 4) pp:
Publication Date(Web):March 2017
DOI:10.1016/j.ceramint.2016.12.018
MoO3/reduced graphene oxide (MoO3/RGO) composites were successfully prepared via a facile one-step hydrothermal method, and evaluated as anode materials for sodium ion batteries (SIBs). The crystal structures, morphologies and electrochemical properties of the as-prepared samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge/discharge tests, respectively. The results show that the introduction of RGO can enhance the electrochemical performances of MoO3/RGO composites. MoO3/RGO composite with 6 wt% RGO delivers the highest reversible capacity of ~208 mA h g−1 at 50 mA g−1 after 50 cycles with good cycling stability and excellent rate performance for SIBs. The excellent sodium storage performance of MoO3/RGO should be attributed to the synergistic effect between MoO3 and RGO, which offers the increased electrical conductivity, the facilitated electron transfer ability and the buffering of volume expansion.
Co-reporter:Haipeng Chu, Wenyan Lei, Xinjuan Liu, Jinliang Li, Wei Zheng, Guang Zhu, Can Li, Likun Pan, Changqing Sun
Applied Catalysis A: General (5 July 2016) Volume 521() pp:19-25
Publication Date(Web):5 July 2016
DOI:10.1016/j.apcata.2016.01.022
Co-reporter:Dongsheng Li, Dong Yan, Xiaojie Zhang, Jiabao Li, Ting Lu, Likun Pan
Journal of Colloid and Interface Science (1 July 2017) Volume 497() pp:
Publication Date(Web):1 July 2017
DOI:10.1016/j.jcis.2017.03.037
Currently, metal-organic frameworks (MOFs) and their derivates have attracted great interest as a new kind of electrode material for energy storage devices, mainly due to their designable framework structures, abundant pore structures, adjustable pore and particle sizes. In this work, porous CuO/reduced graphene oxide (RGO) composites were obtained through the pyrolysis of Cu-based MOFs/graphene oxide under microwave irradiation, and investigated as anode materials for sodium-ion batteries (SIBs). CuO/RGO composites exhibit a maximum specific capacity of 466.6 mA h g−1 after 50 galvanostatic charge/discharge cycles at a current density of 100 mA g−1. Even at a high current density of 2 A g−1, a capacity of 347.6 mA h g−1 is still maintained with stable cycling. The superior electrochemical performance, which is better than those of CuO-based electrodes reported previously, makes the CuO/RGO composites to be applied promisingly as anodes for high-performance SIBs.
Co-reporter:Shujin Hou, Miao Wang, Xingtao Xu, Yandong Li, Yanjiang Li, Ting Lu, Likun Pan
Journal of Colloid and Interface Science (1 April 2017) Volume 491() pp:
Publication Date(Web):1 April 2017
DOI:10.1016/j.jcis.2016.12.033
One of the most challenging issues in developing electrochemical flow capacitor (EFC) technology is the design and synthesis of active electrode materials with high energy density and long cycle life. However, in practical cases, the energy density and cycle ability obtained currently cannot meet the practical need. In this work, we propose a new active material, nitrogen-doped carbon spheres (NCSs), as flowable electrodes for EFC application. The NCSs were prepared via one-pot hydrothermal synthesis in the presence of resorcinol/formaldehyde as carbon precursors and melamine as nitrogen precursor, followed by carbonization in nitrogen flow at various temperatures. The results of EFC experiments demonstrate that NCSs obtained at 800 °C exhibit a high energy density of 13.5 Wh kg−1 and an excellent cycle ability, indicating the superiority of NCSs for EFC application.
Co-reporter:Hongmei Tang, Miao Wang, Ting Lu, Likun Pan
Ceramics International (1 April 2017) Volume 43(Issue 5) pp:4475-4482
Publication Date(Web):1 April 2017
DOI:10.1016/j.ceramint.2016.12.098
Co-reporter:Xingtao Xu, Hongmei Tang, Miao Wang, Yong Liu, Yanjiang Li, Ting Lu and Likun Pan
Journal of Materials Chemistry A 2016 - vol. 4(Issue 41) pp:NaN16100-16100
Publication Date(Web):2016/09/19
DOI:10.1039/C6TA07616E
In this work, porous carbon spheres with hierarchical pores (denoted as hCSs) were fabricated via a sol–gel process using a surfactant-directing assembly strategy and investigated as capacitive deionization (CDI) electrode materials for the first time. By using transmission electron microscopy and N2 adsorption/desorption analyses, a hierarchy of micropores and mesopores was demonstrated to be present in the hCSs. Based on the results of CDI measurements, the hCSs obtained at 800 °C (hCSs-800) displayed the best electrosorption performance of all the hCS samples tested: hCSs-800 exhibited a high electrosorption capacity of 15.8 mg g−1 when the initial NaCl concentration was 500 mg L−1. Furthermore, according to a Kim–Yoon plot analysis, hCSs-800 integrated the merits of both a high electrosorption capacity and fast electrosorption rate, indicating the superiority of these hCSs for CDI applications.
Co-reporter:Dong Yan and Likun Pan
Inorganic Chemistry Frontiers 2016 - vol. 3(Issue 4) pp:NaN468-468
Publication Date(Web):2016/01/12
DOI:10.1039/C5QI00226E
Sodium-ion batteries (SIBs) have attracted great interest for use as the next generation rechargeable batteries due to the abundant sodium natural resources and similar chemistry of lithium and sodium. TiO2 is an attractive candidate as an anode for SIBs due to its high safety, low cost, appropriate voltage platform and good structural stability during repeated charge–discharge processes. However, the sodium storage mechanism of TiO2 for SIBs remains unclear, which appears to be different from the working mechanism in lithium-ion batteries. This article highlights a recent report by Passerini's group, which successfully proposed a new sodium storage mechanism of TiO2 for SIBs.
Co-reporter:Yong Liu, Chunyang Nie, Likun Pan, Xingtao Xu, Zhuo Sun and Daniel H. C. Chua
Inorganic Chemistry Frontiers 2014 - vol. 1(Issue 3) pp:
Publication Date(Web):
DOI:10.1039/C3QI00102D
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Ting Lu, Guang Zhu, Zhuo Sun and Changqing Sun
Catalysis Science & Technology (2011-Present) 2011 - vol. 1(Issue 7) pp:NaN1193-1193
Publication Date(Web):2011/07/11
DOI:10.1039/C1CY00109D
ZnO–graphene composites are successfully synthesized via microwave-assisted reaction of zinc sulfate in aqueous solution with a graphite oxide dispersion using a microwave synthesis system. Their morphology, structure and photocatalytic performance in reduction of Cr(VI) are characterized by scanning electron microscopy, X-ray diffraction spectroscopy and UV-vis absorption spectrophotometer, respectively. The results show that in the composite the graphene nanosheets are decorated densely by ZnO nanosheets, which display a good combination between graphene and ZnO nanosheets. The ZnO–graphene composite exhibits an enhanced photocatalytic performance in the reduction of Cr(VI) with a removal rate of 98% under UV light irradiation as compared with pure ZnO (58%) due to the increased light absorption intensity and range, as well as the reduction of electron–hole pair recombination with the introduction of graphene.
Co-reporter:Tian Lv, Likun Pan, Xinjuan Liu and Zhuo Sun
Catalysis Science & Technology (2011-Present) 2012 - vol. 2(Issue 11) pp:NaN2301-2301
Publication Date(Web):2012/06/01
DOI:10.1039/C2CY20023F
ZnO–reduced graphene oxide (RGO)–carbon nanotube (CNT) composites were successfully synthesized via microwave-assisted reduction of a graphite oxide dispersion in zinc nitrate solution with a CNT suspension. Their photocatalytic performance in the degradation of methylene blue was investigated and the results show that the CNTs play an important role in the enhancement of the photocatalytic performance and the ZnO–RGO–CNT composite with 3.9 wt% CNTs achieves a maximum degradation efficiency of 96% under UV light irradiation for 260 min as compared with ZnO–RGO (88%) due to the increased light absorption and the reduced charge recombination with the introduction of CNTs.
Co-reporter:Guang Zhu, Likun Pan, Jie Yang, Xinjuan Liu, Hengchao Sun and Zhuo Sun
Journal of Materials Chemistry A 2012 - vol. 22(Issue 46) pp:NaN24329-24329
Publication Date(Web):2012/07/09
DOI:10.1039/C2JM33219A
Nest-shaped TiO2 (NS-TiO2) structures were fabricated by an electrospinning technique and used as an effective scattering layer on the top of TiO2 nano-particle electrodes in dye sensitized solar cells (DSSCs). The NS-TiO2 scattering layer enhanced the photocurrent of DSSCs due to the enhanced light harvesting via the improved light scattering and lower electron transfer resistance. Under one sun illumination (AM 1.5G, 100 mW cm−2), a high efficiency of 8.02% was achieved for the cell with a NS-TiO2 scattering layer, which was an increase of 7.1% compared to the cell without a scattering layer (7.49%).
Co-reporter:Guang Zhu, Likun Pan, Ting Lu, Tao Xu and Zhuo Sun
Journal of Materials Chemistry A 2011 - vol. 21(Issue 38) pp:NaN14875-14875
Publication Date(Web):2011/08/19
DOI:10.1039/C1JM12433A
Reduced graphene (RG)-carbon nanotubes (CNTs) composite films are successfully fabricated by electrophoretic deposition and used as counter electrodes of dye-sensitized solar cells. RG is obtained by microwave-assisted reduction of graphite oxide dispersion in aqueous solution using a microwave synthesis system. By the optimization of CNTs content, photovoltaic conversion efficiency of the cell with RG-CNTs counter electrode reaches a maximum of 6.17% at one sun (AM 1.5 G, 100 mW cm−2) which is comparable to the cell with conventional Pt counter electrode. The results suggest that the RG-CNTs composite films provide a potential feasibility for replacing conventional Pt counter electrodes for DSSCs.
Co-reporter:Likun Pan, Xinjuan Liu, Zhuo Sun and Chang Q. Sun
Journal of Materials Chemistry A 2013 - vol. 1(Issue 29) pp:NaN8326-8326
Publication Date(Web):2013/05/03
DOI:10.1039/C3TA10981J
Nanostructured photocatalysts have attracted considerable interest due to their wide range of applications in processes such as organic pollutant degradation, heavy metal reduction, air and water purification, hydrogen production, etc. Pursuing high catalytic efficiency is the foremost goal in the field. One of the current key issues is to search for suitable photocatalysts to enhance light harvesting in the UV or visible light region. In this treatise, the microwave-assisted solution-phase synthesis of various nanomaterials including semiconductor oxides and sulfides, Bi-based oxides, as well as nanocomposites including carbon nanotube-based and graphene-based composites is systematically presented with demonstrations of the advantages of the microwave-assisted process over traditional synthesis methods including solid state or vapor reactions and hydrothermal or solvothermal processes. Application of these nanomaterials as photocatalysts for the degradation of pollutants in water or air, removal of Cr(VI) as well as hydrogen evolution is also demonstrated, showing the improved photocatalytic activities compared with the ones synthesized via traditional methods.
Co-reporter:Haibo Li, Likun Pan, Chunyang Nie, Yong Liu and Zhuo Sun
Journal of Materials Chemistry A 2012 - vol. 22(Issue 31) pp:
Publication Date(Web):
DOI:10.1039/C2JM32207B
Co-reporter:Xinjuan Liu, Xiaojun Wang, Huili Li, Jinliang Li, Likun Pan, Jing Zhang, Guoquan Min, Zhuo Sun and Changqing Sun
Dalton Transactions 2015 - vol. 44(Issue 1) pp:NaN103-103
Publication Date(Web):2014/10/20
DOI:10.1039/C4DT01252F
ZnO–NaSrBO3:Tb3+ (ZNT) composites were successfully synthesized via microwave-assisted reaction of the ZnO precursor with a NaSrBO3:Tb3+ suspension using a microwave synthesis system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-vis absorption spectroscopy, fluorescence spectrophotometry and electrochemical impedance spectroscopy, respectively. The results show that the ZNT composites exhibit enhanced photocatalytic activity in the degradation of MB with a maximum degradation rate of 97% under visible light irradiation compared with pure ZnO (12%), which is ascribed to the increased light absorption and the reduction of photoelectron–hole pair recombination in ZnO with the introduction of NaSrBO3:Tb3+, as well as the light down-converting effect of NaSrBO3:Tb3+, which facilitates the self-sensitized degradation of MB.
Co-reporter:Hengchao Sun, Likun Pan, Guang Zhu, Xianqing Piao, Li Zhang and Zhuo Sun
Dalton Transactions 2014 - vol. 43(Issue 40) pp:NaN14941-14941
Publication Date(Web):2014/07/31
DOI:10.1039/C4DT01276C
Long afterglow Sr4Al14O25:Eu,Dy phosphors were introduced into the TiO2 photoanode of CdS quantum dot-sensitized solar cells (QDSSCs) as both a scattering and down converting layer, and the photovoltaic performances of the cells were investigated. The results show that the cell with Sr4Al14O25:Eu,Dy achieves a power conversion efficiency of 1.40%, which is an increase of 38% compared to the cell without Sr4Al14O25:Eu,Dy (1.02%). The performance improvement is attributed to enhanced light harvesting via improved light absorption and scattering processes. After a single sun illumination for 1 min and subsequent removal of the light source, the cell with Sr4Al14O25:Eu,Dy could be driven even in the dark by the long persistent light from Sr4Al14O25:Eu,Dy.
Co-reporter:Yong Liu, Likun Pan, Xingtao Xu, Ting Lu, Zhuo Sun and Daniel H. C. Chua
Journal of Materials Chemistry A 2014 - vol. 2(Issue 48) pp:NaN20972-20972
Publication Date(Web):2014/10/28
DOI:10.1039/C4TA04578E
Carbon nanorods (CNRs) were fabricated from natural based nanocrystalline cellulose through a simple thermal treatment at 800, 1000 and 1200 °C. The morphology, structure and electrochemical performance of CNRs were characterized by atomic force microscopy, Raman spectroscopy, nitrogen adsorption–desorption, cyclic voltammetry and electrochemical impedance spectroscopy. Their electrosorption performance in NaCl solution was studied. The results show that CNRs treated at 1200 °C exhibit the highest specific capacitance of 264.19 F g−1 and electrosorption capacity of 15.12 mg g−1 with the initial NaCl concentration of 500 mg l−1, due to their high specific surface area and low charge transfer resistance.
Co-reporter:Yong Liu, Xingtao Xu, Miao Wang, Ting Lu, Zhuo Sun and Likun Pan
Journal of Materials Chemistry A 2015 - vol. 3(Issue 33) pp:NaN17311-17311
Publication Date(Web):2015/07/20
DOI:10.1039/C5TA03663A
Nitrogen-doped carbon nanorods (NCNRs) were prepared from naturally based nanocrystalline cellulose through simple freeze drying and subsequent thermal treatment under an ammonia atmosphere at different temperatures. The morphology, structure and electrochemical performance of the NCNRs were characterized using scanning electron microscopy, transmission electron microscopy, nitrogen adsorption–desorption, X-ray photoelectron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy, and their electrosorption performance in NaCl solution was studied. The results show that NCNRs treated at 1000 °C exhibit an extremely high electrosorption capacity of 17.62 mg g−1 when the initial NaCl concentration is 500 mg l−1, which shows great improvement compared with their undoped counterparts. The nitrogen doping proved to be a very effective method for improving the electrosorption performance, and the NCNRs should be very promising candidates as electrode materials for CDI applications.
Co-reporter:Taiqiang Chen, Likun Pan, Ting Lu, Conglong Fu, Daniel H. C. Chua and Zhuo Sun
Journal of Materials Chemistry A 2014 - vol. 2(Issue 5) pp:NaN1267-1267
Publication Date(Web):2013/11/11
DOI:10.1039/C3TA14037G
A fast microwave-assisted approach was developed to fabricate carbon microspheres (CSs) using sucrose as the precursor in a microwave system. After thermal treatment at 300, 500, 700 and 1000 °C, the CSs were used as anode materials for sodium ion batteries (SIBs). The results show that CSs treated at 500 °C exhibit a maximum capacity of 183 mA h g−1 at a current density of 30 mA g−1 after 50 cycles, and even at a high current density of 1000 mA g−1 a capacity of 83 mA h g−1 is maintained. The high capacity, good cycling stability and excellent rate performance of CSs, due to their unique spherical structure, make them a promising candidate for anode materials for SIBs.
Co-reporter:Dong Yan, Caiyan Yu, Dongsheng Li, Xiaojie Zhang, Jiabao Li, Ting Lu and Likun Pan
Journal of Materials Chemistry A 2016 - vol. 4(Issue 28) pp:NaN11085-11085
Publication Date(Web):2016/06/20
DOI:10.1039/C6TA04906K
TiO2 is a promising anode for sodium-ion batteries (SIBs) due to its inherent safety, low cost, good structural stability during the sodium-ion storage process and appropriate voltage platform. However, unsatisfactory electrical conductivity hinders its applications. Here we demonstrate that doping TiO2 nanotubes with Ni2+via an initial sol–gel method, subsequent hydrothermal process and final thermal treatment can balance the high conductivity and good structural stability of TiO2 to improve the sodium-ion storage performance. The resultant sample exhibits a high charge capacity of 286 mA h g−1 after 100 cycles at a current density of 50 mA g−1 and even at a high current density of 5 A g−1, a capacity of 123 mA h g−1 is maintained after 2000 cycles. It is believed that the strategy in this work can provide a useful pathway towards enhancing the electrochemical performance of TiO2 anodes for SIBs.
Co-reporter:Xingtao Xu, Yong Liu, Ting Lu, Zhuo Sun, Daniel H. C. Chua and Likun Pan
Journal of Materials Chemistry A 2015 - vol. 3(Issue 25) pp:NaN13425-13425
Publication Date(Web):2015/05/20
DOI:10.1039/C5TA01889G
Capacitive deionization (CDI) is an emerging technology offering a green and efficient route to obtain clean water. Up to now, the key of CDI technology has been focused on the exploration of electrode materials with a rationally designed structure and excellent performance, because the electrosorption performance of the carbon-based electrodes reported to date cannot meet the demands of practical applications of CDI. Herein, novel graphene/carbon nanotubes (CNTs) hybrid sponge (GNS) structures were designed and fabricated via directly freeze-drying graphene oxide/CNTs mixed solution followed by annealing in nitrogen atmosphere. The morphology, structure and electrochemical performance of GNS were characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, nitrogen adsorption–desorption, cyclic voltammetry and electrochemical impedance spectroscopy. The results show that GNS with 20 wt% CNTs has a maximum specific surface area of 498.2 m2 g−1 and a highest specific capacitance of 203.48 F g−1 among all the samples. When used as CDI electrode, it exhibits an ultrahigh electrosorption capacity of 18.7 mg g−1, and, to our knowledge, this value is superior to those of other carbon electrodes reported recently. GNS should be a promising electrode material for high-performance CDI.
Co-reporter:Xinjuan Liu, Xiaojun Wang, Huili Li, Likun Pan, Tian Lv, Zhuo Sun and Changqing Sun
Journal of Materials Chemistry A 2012 - vol. 22(Issue 32) pp:NaN16298-16298
Publication Date(Web):2012/06/25
DOI:10.1039/C2JM33008C
ZnO–Y3Al5O12:Ce3+ composites were successfully synthesized via a microwave-assisted reaction of the ZnO precursor with a Y3Al5O12:Ce3+ suspension using a microwave synthesis system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectroscopy, fluorescence spectrophotometer, and UV-vis absorption spectrophotometer. The results show that the introduction of Y3Al5O12:Ce3+ can enhance the photocatalytic performance of ZnO with a maximum MB degradation rate of 93% under visible light irradiation compared with pure ZnO (13%) mainly due to the light down-converting effect of Y3Al5O12:Ce3+, which facilitates the self-sensitized destruction of MB.
Co-reporter:Yong Liu, Ting Lu, Zhuo Sun, Daniel H. C. Chua and Likun Pan
Journal of Materials Chemistry A 2015 - vol. 3(Issue 16) pp:NaN8700-8700
Publication Date(Web):2015/03/11
DOI:10.1039/C5TA00435G
Ultra-thin carbon nanofiber networks (bc-CNFs) were prepared from natural-based bacterial cellulose pellicle through freeze drying and subsequent carbonization at different temperatures. The morphology, structure and electrochemical performance of the bc-CNFs were characterized by field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, nitrogen adsorption–desorption, Fourier transform infrared spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. Their electrosorption performance in NaCl solution was studied and compared with those of carbon nanotubes (CNTs) and electrospun carbon nanofibers (e-CNFs). The results show that the bc-CNFs treated at 800 °C exhibited excellent desalination performance with an electrosorption capacity of 12.81 mg g−1 in 1000 mg l−1 NaCl solution, much higher than those of the CNTs (3.78 mg g−1) and the e-CNFs (6.56 mg g−1). The excellent performance of the bc-CNFs is ascribed to their high specific surface area, low charge transfer resistance and superior hydrophility.
Co-reporter:Taiqiang Chen, Yong Liu, Likun Pan, Ting Lu, Yefeng Yao, Zhuo Sun, Daniel H. C. Chua and Qun Chen
Journal of Materials Chemistry A 2014 - vol. 2(Issue 12) pp:NaN4121-4121
Publication Date(Web):2014/01/10
DOI:10.1039/C3TA14806H
A simple and scalable electrospinning process followed by thermal treatment was used to fabricate carbon nanofibers (CFs). The as-prepared CFs were investigated as anode materials for sodium ion batteries (SIBs). Remarkably, due to their weakly ordered turbostratic structure and a large interlayer spacing between graphene sheets, the CFs exhibit a dominant adsorption/insertion sodium storage mechanism that shows high reversibility. As a result, the CFs show excellent electrochemical performance, especially cycle stability (97.7% capacity retention ratio over 200 cycles). Reversible capacities of 233 and 82 mA h g−1 are obtained for the CFs at a current density of 0.05 A g−1 and even a high current density of 2 A g−1, respectively. The excellent cycle performance, high capacity and good rate capability make the CFs promising candidates for practical SIBs.
Co-reporter:Yong Liu, Xingtao Xu, Miao Wang, Ting Lu, Zhuo Sun and Likun Pan
Chemical Communications 2015 - vol. 51(Issue 60) pp:NaN12023-12023
Publication Date(Web):2015/06/16
DOI:10.1039/C5CC03999A
Porous carbon polyhedra (PCP) were prepared through direct carbonization of zeolitic imidazolate framework-8 and used as an electrode material for capacitive deionization. The results show that PCP treated at 1200 °C exhibit the highest electrosorption capacity of 13.86 mg g−1 when the initial NaCl concentration is 500 mg l−1, due to their high accessible surface area and low charge transfer resistance.
Co-reporter:Guang Zhu, Xiaojun Wang, Huili Li, Likun Pan, Hengchao Sun, Xinjuan Liu, Tian Lv and Zhuo Sun
Chemical Communications 2012 - vol. 48(Issue 7) pp:NaN960-960
Publication Date(Web):2011/11/24
DOI:10.1039/C1CC16089C
Y3Al5O12:Ce phosphors have been prepared and used as an effective scattering layer on top of a transparent layer of nanocrystalline TiO2 for dye sensitized solar cells (DSSCs). The Y3Al5O12:Ce scattering layer increases the photocurrent of DSSCs due to the enhanced light harvesting mainly via the improved light absorption and scattering. Under one sun illumination (AM 1.5G, 100 mW cm−2), a high efficiency of 7.91% was achieved for the cell with a Y3Al5O12:Ce scattering layer, which is an increase of 13.5% compared to the cell without a scattering layer (6.97%).
Co-reporter:Tian Lv, Likun Pan, Xinjuan Liu, Ting Lu, Guang Zhu, Zhuo Sun and Chang Q. Sun
Catalysis Science & Technology (2011-Present) 2012 - vol. 2(Issue 4) pp:NaN758-758
Publication Date(Web):2011/12/09
DOI:10.1039/C2CY00452F
One-step synthesis of CdS–TiO2–chemically reduced graphene oxide (RGO) composites was carried out using microwave-assisted reduction of graphite oxide in CdS precursor solution with TiO2 suspension. The photocatalytic performance of CdS–TiO2–RGO composites in degradation of methyl orange was examined. Results show that the RGO addition could enhance the photocatalytic performance of CdS–TiO2 composites with maximum degradation efficiency of 99.5% under visible light irradiation as compared with the pure TiO2 (43%) and CdS–TiO2 (79.9%) composites due to the increase of specific surface area for more adsorbed MO and the reduction of electron–hole pair recombination with the introduction of RGO.
Co-reporter:Dong Yan, Caiyan Yu, Ying Bai, Weifeng Zhang, Taiqiang Chen, Bingwen Hu, Zhuo Sun and Likun Pan
Chemical Communications 2015 - vol. 51(Issue 39) pp:NaN8264-8264
Publication Date(Web):2015/04/08
DOI:10.1039/C4CC10020D
Sn-doped TiO2 nanotubes were employed as anodes for sodium ion batteries. The electrodes exhibit a high maximum charge capacity of 257 mA h g−1 after 50 cycles at a current density of 50 mA g−1 with good rate capability and especially excellent cycling stability, mainly due to the increase of electrical conductivity by Sn doping.
Co-reporter:Taiqiang Chen, Likun Pan, T. A. J. Loh, D. H. C. Chua, Yefeng Yao, Qun Chen, Dongsheng Li, Wei Qin and Zhuo Sun
Dalton Transactions 2014 - vol. 43(Issue 40) pp:NaN14935-14935
Publication Date(Web):2014/06/05
DOI:10.1039/C4DT01223B
Nitrogen-doped carbon microspheres (NCSs) were fabricated via a simple, fast and energy-saving microwave-assisted method followed by thermal treatment under an ammonia atmosphere. NCSs thermally treated at different temperatures were investigated as anode materials for lithium ion batteries (LIBs). The results show that NCSs treated at 900 °C exhibit a maximum reversible capacity of 816 mA h g−1 at a current density of 50 mA g−1 and preserve a capacity of 660 mA h g−1 after 50 cycles, and even at a high current density of 1000 mA g−1, a capacity of 255 mA h g−1 is maintained. The excellent electrochemical performance of NCSs is due to their porous structure and nitrogen-doping. The present NCSs should be promising low-cost anode materials with a high capacity and good cycle stability for LIBs.
Co-reporter:Haibo Li, Ting Lu, Likun Pan, Yanping Zhang and Zhuo Sun
Journal of Materials Chemistry A 2009 - vol. 19(Issue 37) pp:NaN6779-6779
Publication Date(Web):2009/07/21
DOI:10.1039/B907703K
Graphene has been synthesized by the modified Hummers method and used as electrosorptive electrodes for capacitive deionization. Batch-mode experiments in NaCl solutions at low voltage (≤2 V) are conducted in a continuously recycling system to investigate the electrosorption performance of graphene. The results show that the graphene exhibits a high electrosorption capacity of 1.85 mg/g. The ion sorption follows a Freundlich isotherm, indicating monolayer adsorption. And the electrosorption of NaCl onto graphene electrodes is driven by a physisorption process by taking into account the thermodynamic parameters.
Co-reporter:Xingtao Xu, Miao Wang, Yong Liu, Ting Lu and Likun Pan
Journal of Materials Chemistry A 2016 - vol. 4(Issue 15) pp:NaN5473-5473
Publication Date(Web):2016/03/14
DOI:10.1039/C6TA00618C
Capacitive deionization (CDI) is an emerging desalination technique to offer clean water. In order to obtain high CDI performance, a rationally designed structure of electrode materials has been an urgent need for CDI application. Here for the first time a hierarchical porous carbon nanotube (CNT)/porous carbon polyhedra (PCP) (hCNT/PCP) hybrid was fabricated via in situ insertion of CNTs into ZIF-8 and a subsequent pyrolysis process. The potential of the hCNT/PCP hybrid for CDI application was demonstrated, and the results indicate that the hCNT/PCP hybrid exhibits a high electrosorption capacity of 20.5 mg g−1 with stable cycling stability due to its novel CNT-inserted-PCP porous structure, high specific surface area and good electrical conductivity. It should be expected that hCNTs/PCP should be a promising candidate for highly efficient CDI electrode materials.
Co-reporter:Xinjuan Liu, Likun Pan, Tian Lv, Guang Zhu, Zhuo Sun and Changqing Sun
Chemical Communications 2011 - vol. 47(Issue 43) pp:NaN11986-11986
Publication Date(Web):2011/09/30
DOI:10.1039/C1CC14875C
CdS–reduced graphene oxide (RGO) composites are successfully synthesized via the microwave-assisted reduction of graphite oxide in a CdS precursor solution using a microwave synthesis system. The photocatalytic performances of CdS–RGO composites in the reduction of Cr(VI) are investigated. The results show that CdS–RGO composites exhibit enhanced photocatalytic performance for the reduction of Cr(VI) with a maximum removal rate of 92% under visible light irradiation as compared with pure CdS (79%) due to the increased light absorption intensity and the reduction of electron–hole pair recombination in CdS with the introduction of RGO.
Co-reporter:Xinjuan Liu, Likun Pan, Taiqiang Chen, Jinliang Li, Kai Yu, Zhuo Sun and Changqing Sun
Catalysis Science & Technology (2011-Present) 2013 - vol. 3(Issue 7) pp:NaN1809-1809
Publication Date(Web):2013/03/26
DOI:10.1039/C3CY00013C
SnO2 quantum dots (QDs) were successfully synthesized via a microwave-assisted reaction of a SnO2 precursor in an aqueous solution using a microwave system. The morphology, structure and photocatalytic performance in the degradation of methylene blue (MB) were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, UV-vis absorption/reflectance spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the SnO2 QDs synthesized at a pH value of 5 exhibit an optimal photocatalytic performance with a MB degradation rate of 90% at 240 min under visible light irradiation due to their easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.
Co-reporter:Hengchao Sun, Likun Pan, Xianqing Piao and Zhuo Sun
Journal of Materials Chemistry A 2013 - vol. 1(Issue 21) pp:NaN6392-6392
Publication Date(Web):2013/03/20
DOI:10.1039/C3TA10596B
An efficient bifunctional structured layer composed of long afterglow SrAl2O4:Eu,Dy phosphors on top of a transparent layer of nanocrystalline TiO2 was fabricated for use in CdS quantum dot-sensitized solar cells (QDSSCs). The introduction of SrAl2O4:Eu,Dy increases the photocurrent of the QDSSCs mainly due to enhanced light harvesting abilities via improved light absorption and scattering. Under one sun illumination (AM 1.5G, 100 mW cm−2), cells containing SrAl2O4:Eu,Dy show a marked improvement in their conversion efficiency (1.24%) compared with cells without SrAl2O4:Eu,Dy (0.98%). After one sun illumination for 1 min, after which the light source was turned off, cells containing SrAl2O4:Eu,Dy show an efficiency of 0.07% under dark conditions due to the irradiation by the long persistent light from SrAl2O4:Eu,Dy. The present strategy should provide a possibility to fulfil the operation of solar cells even in the dark.
Co-reporter:Xiaojie Zhang, Wei Qin, Dongsheng Li, Dong Yan, Bingwen Hu, Zhuo Sun and Likun Pan
Chemical Communications 2015 - vol. 51(Issue 91) pp:NaN16416-16416
Publication Date(Web):2015/09/17
DOI:10.1039/C5CC06924F
Porous CuO/Cu2O composite hollow octahedrons were synthesized simply by annealing Cu-based metal–organic framework templates. When evaluated as anode materials for sodium ion batteries, they exhibit a high maximum reversible capacity of 415 mA h g−1 after 50 cycles at 50 mA g−1 with excellent cycling stability and good rate capability.
Co-reporter:Xinjuan Liu, Haipeng Chu, Jinliang Li, Lengyuan Niu, Can Li, Huili Li, Likun Pan and Chang Q. Sun
Catalysis Science & Technology (2011-Present) 2015 - vol. 5(Issue 10) pp:NaN4740-4740
Publication Date(Web):2015/06/10
DOI:10.1039/C5CY00622H
Semiconductor photocatalysis has attracted tremendous attention due to its potential in environmental remediation, clean energy production and chemical reaction technology. Pursuing high efficiencies is a core task in the field. One of the major factors in photocatalysis is the limited light absorption of photocatalysts in the incident solar spectrum. In this treatise, we will survey recent advancements in light-conversion phosphor-based composites including up-conversion, down-conversion, and long afterglow phosphor-based composites for photocatalysis.
