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Science China Chemistry 2015年第12期58卷 1912-1917页

作者： Lifeng Yin Lili Xie Yueping Bao Junfeng Niu State Key Laboratory of Water Environment Simulation

A novel visible light-driven photocatalyst, lithium vanadium phosphate sphere(LVPS), was prepared by a ball-milling method. For enhancing the photocatalytic performance, LVPS was further modified with silver(ALVPS) by a UV-light photo- reduction method. After modification, the crystalline phase of LVPS did not change, however, the UV-Vis diffuse reflectance spectrum of ALVPS was extended to 656 nm, which greatly improved its photoabsorptivity for visible light and enhanced its electron donating capacity. Under the irradiation of sunlight or visible light(>400 nm), ALVPS can rapidly remove fipronil(a persistent organic pollutant, 5 mg L?1) from aqueous solution. More than 99.7% of fipronil was removed by ALVPS after 0.5 h of irradiation, yielding a much higher removal rate than those achieved by nano-Ti O2 and Bi2O3. Photo-generated carrier trapping experiments were conducted to elucidate the photocatalytic degradation mechanism further. Hydrogen peroxide and potassium bromate suppressed the photocatalytic activity of ALVPS, while superoxide dismutase and sodium azide reinforced it, verifying that photo-generated electrons played a key role in the photochemical reaction.

关键词： lithium vanadium phosphate sphere visible light irradiation photocatalysis degradation

Synthesis and electrochemical performance of La-doped Li_3V_(2-x)La_x(PO_4)_3 cathode materials for lithium batteries

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Rare Metals 2011年第2期30卷 115-119页

作者： JIANG Boquan HU Shufen WANG Minwei OUYANG Xiaoping GONG Zhenyu School of Environmental and Chemical Engineering Nanchang University Nanchang 330031 China

La-doped Li3V2-xLax（PO4）3 （ x = 0.01, 0.02, and 0.03） cathode materials for lithium ion batteries were synthesized by the microwave-assisted carbothermal reduction method （MW-CTR）. The structures and properties of the prepared samples were investigated by X-ray diffraction （XRD） and electrochemical measurements. The results showed that all the three Li3V2-xLax（PO4）3 samples had the same monocfinic structures and sharper diffraction peaks of the crystal plane compared with those of the undoped Li3V2（PO4）3. The initial charge/discharge specific capacity, coulomb efficiency, and discharge decay rate of all the three Li3V2-xLax（PO4）3 samples were superior to those of the undoped Li3V2（PO4）3 sample, and the Li3V1.98La0.02（PO4）3 sample exhibited the best features among the three La-doped Li3V2-xLax（PO4）3 samples. Electrochemical impedance spectroscopy （EIS） demonstrated that the Li3V1.98Lao.02（PO4）3 sample had a lower charge transfer resistance and a higher Li ion diffusion coefficient compared with the undoped Li3V2 （PO4）3 sample.

关键词： lithium batteries cathode materials carbothermal reduction microwaves lithium vanadium phosphate lanthanum

Nano-Li3V2（PO4）3/C Synthesized by Thermal Polymerization Method as Cathode Material for lithium Ion Batteries

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Chinese Journal of Chemical Physics 2016年第6期29卷 699-702,I0001页

作者： Bin Cheng Lian-sheng Jiao Zhong-feng Tang Sheng-jie Zhang Hong-li Chen Chun-hua Chen CASKeyLaboratoryofMaterialsforEnergyConversions DepartmentofMaterialsScienceandEngineering&CollaborativeInnovationCenterofSuzhouNanoScienceandTechnologyUniversityofScienceandTechnologyofChinaHefei230026China DepartmentofChemistry HebeiNormalUniversityforNationalitiesChengde067000China

A nano-Li3V2（PO4）3/C powder was successfully prepared by a thermal polymerization method. The particle sizes of the intermediate product powder and the final product Li3V2（PO4）3 are all less than 200 nm. The carbon is partially coated on the surface of Li3V2（PO4）3 particles and the rest exists between particles with a total carbon content of 4.6wt%. This nano-Li3V2（PO4）3/C sample shows a discharge capacity of 124 mAh/g with-out capacity fading after 100 cycles at 0.1 C in the voltage rang of 3.0-4.3 V. Excellent rate performance is also achieved with a capacity of 80 mAh/g at 20 C in 3.0-4.3 V and 100 mAh/g at 10 C in 3.0-4.8 V. This study suggests that the thermal polymerization method is suitable to synthesize nano-Li3V2（PO4）3/C materials.

关键词： lithium vanadium phosphate Thermal polymerization Nanoparticles Acrylic acid

Effect of Mg doping on electrochemical performance of Li_3V_2(PO_4)_3/C cathode material for lithium ion batteries

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Transactions of Nonferrous Metals Society of China 2015年第7期25卷 2266-2271页

作者：罗韵泽何利华刘旭恒中南大学冶金与环境学院长沙410083

Li3Mg（2x）V（2-2x）（PO4）3/C（x=0,0.05,0.1,0.2） composites were synthesized by carbothermic reduction,using a self-made MgNH4PO4/MgHPO4 compound as Mg-doping agent.X-ray diffraction（XRD）,scanning electron microscope（SEM）,electrochemical performance tests were employed to investigate the effect of Mg doping on Li3V2（PO4）3/C *** results showed that a proper quantity of Mg doping was beneficial to the reduction of charge transfer resistance of Li3V2（PO4）3/C compound without changing the lattice structure,which led to larger charge/discharge capacity and better cycle performance especially at high current ***3Mg（2x）V（2-2x）（PO4）3/C sample with x=0.05 exhibited a better performance with initial charge/discharge capacity of146/128 mA·h/g and discharge capacity of 115 mA·h/g at 5C,while these two figures were 142/118 mA·h/g and 90 mA·h/g respectively for samples without Mg doping,indicating that a proper amount of doped Mg can improve the electrochemical performance of LVP *** of these proved that,as a trial Mg dopant,the synthesized MgNH4PO4/MgHPO4 compound exhibited well doping effect.

关键词： lithium vanadium phosphate Mg-doping cathode materials carbothermic reduction

Synthesis and electrochemical performance of Li_(3-2x)Mg_xV_2(PO_4)_3/C composite cathode materials for lithium-ion batteries

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Transactions of Nonferrous Metals Society of China 2015年第6期25卷 1978-1985页

作者：尹武梅张婷婷朱庆陈权启李谷才张灵志湘潭大学化学学院湘潭411105 桂林理工大学化学与生物工程学院桂林541004 湖南工程学院化学化工学院湘潭411104

The Li3 2xMgxV2（PO4）3/C （x-=0, 0.01, 0.03 and 0.05） composites were prepared by a sol-gel method and characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical measurements. The XRD results reveal that a small amount of Mg2＋ doping into Li sites does not significantly change the monoclinic structure of Li3V2（PO4）3, but Mg-doped Li3W2（PO4）3 has larger cell volume than the pristine Li3V2（PO4）3. All Mg-doped composites display better electrochemical performance than the pristine one, and Liz.94Mgo.03Vz（P04）3/C composite exhibits the highest capacity and the best cycle performance among all above-mentioned composites. The analysis of Li＋ diffusion coefficients in Li3V2（PO4）3/C and Li2.94Mgo.03V2（P04）3/C indicates that rapid Li＋ diffusion results from the doping of Mg2＋ and the rapid Li＋ diffusion is responsible for the better electrochemical performance of Mg-doped Li3V2（PO4）3/C composite cathode materials.

关键词： lithium-ion batteries lithium vanadium phosphate diffusion coefficient sol gel method

PEG-combined liquid phase synthesis and electrochemical properties of carbon-coated Li_3V_2(PO_4)_3

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Transactions of Nonferrous Metals Society of China 2015年第4期25卷 1241-1247页

作者：王任衡李新海王志兴郭华军黄斌中南大学冶金与环境学院长沙410083

The carbon-coated monoclinic Li3V2(PO4)3(LVP) cathode materials were successfully synthesized by liquid phase method using PEG as reducing agent and carbon source. The effects of relative molecular mass of PEG on the properties of Li3V2(PO4)3/C were evaluated by X-ray diffraction(XRD), scanning electron microscope(SEM) and electrochemical performance tests. The SEM images show that smaller size particles are obtained by adding larger and smaller PEGs. The electrochemical cycling of Li3V2(PO4)3/C prepared by both PEG200 and PEG20 k has a high initial discharge capacity of 131.1 mA·h/g at 0.1C during 3.0-4.2 V, and delivers a reversible discharge capacity of 123.6 m A·h/g over 30 cycles, which is better than that of other samples. The improvement in electrochemical performance is caused by its improved lithium ion diffusion coefficient for the macroporous morphology, which is verified by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS).

关键词： lithium-ion battery lithium vanadium phosphate PEG carbon-coating liquid phase method

Research on Preparation of the Composite Materials LiFePO4-Li3V2（PO4）3

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International Journal of Technology Management 2014年第4期 98-100页

作者： Haoyu JIANG Jianrong Xiao Hang Zhao College of Science Guilin University of Technology Guilin Guangxi 541006 China

The article developed a lithium iron phosphate - composite cathode material of lithium vanadium phosphate. Using X-ray diffraction （XRD）, electronic scanning electron microscopy surface （SEM）, laser particle size analyzer, carbon and sulfur analyzer, and X-ray photoelectron spectroscopy, etc. for the prepared composites were characterized and found the material is mainly crystalline structure of lithium iron phosphate, and lithium vanadium, wherein a small amount of impurities; finer particle size of the material, the particle size distribution is narrow and uniform, smooth particle surface, wrapping in good carbon composite with other materials prepared in comparison the case has a carbon content of about optimum conductivity. To assemble the material into a cell after the 0.1C, IC, 2C when and 5C, the first discharge capacity were 160,145,127 and 109 mA·h·g^-1, after 50 cycles, the discharge capacity of 162, respectively, 144,126 and 106 mA·h·g^-1, which showed good rate characteristics and cycle characteristics.

关键词： lithium iron phosphate lithium vanadium phosphate graphene composite materials