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Journal of Wuhan University of Technology(materials Science) 2012年第2期27卷 212-216页

作者：陈玉红申玉双 Department of Chemical and Environmental Engineering Hebei Chemical & Pharmaceutical Vocational Technology College

In order to improve the electrochemical performance and thermal stability of Li1.05Co1/3Nil/3Mnl/302 materials, Lil.05CO0.3 Ni0.35Mno.3Mo.0502（M=Ge,Sn） cathode materials were synthesized via co-precipitation method. The structure, electrochemical performance and thermal stability were characterized by X-ray diffraction（XRD）, charge/discharge cycling, cyclic voltammetry（CV）, electrochemical impedance spectroscopy（EIS） and differential scanning calorimetry（DSC）. ESEM showed that Sn-doped and Ge- doped slightly increased the size of grains. XRD and CV showed that Sn-doped and Ge-doped powders were homogeneous and had the better layered structure than the bare one. Sn-doped and Ge-doped improved high rate discharge capacity and cycle-life performance. The reason of the better cycling performance of the doped one was the increasing of lithium-ion diffusion rate and charge transfer rate. Sn-doped and Ge-doped also improved the mateials thermal stability.

关键词： lithium-ion batteries cathode materials Gedoped Sn-doped coprecipitation

Excess capacity on compound phases of Li_(2)FeTiO_(4) composite cathode materials synthesized by hydrothermal reaction using optional titanium sources to boost battery performance

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Chinese Chemical Letters 2020年第12期31卷 3200-3204页

作者： Liu Yang Shaohua Luo Yafeng Wang Yang Zhan Qing Wang Yahui Zhang Xin Liu Wenning Mu Fei Teng School of materials Science and Engineering Northeastern UniversityShenyang 110819China School of Resources and materials Northeastern University ar QinhuangdaoQinhuangdao 066004China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei PYrovince Qinhuangdao 066004China Qinhuangdao Laboratory of Resources Cleaner Conversion and Efficient Utilization Qinhuangdao 066004China

Li_(2)FeTiO_(4) composites have been produced using commercial LiAC,FeCl_(2) and different titanium sources by hydrothermal synthesis(HS)at 175℃and subsequent annealing at 700℃.Impure phase TiO_(2),Fe_(2)O_(3) and FeTi0_(4) were detected out among the Li_(2)FeTiO_(4) composites with different titanium sources.Micron and nano-sized particles of Li2FeTiO4 were prepared from various titanium raw materials,with nano-sized particles predominating when titanium raw materials were layered hydrogen titanate nanowire(H2Ti3O7 NW,HTO-NW)and titanium oxide nanotubes(TiO_(2) NB).The Li_(2)FeTiO_(4) composites synthesized by HTO-NW shows a primary particle size of 50-200 nm of high crystallinity staggered with undissolved nanowire with a diameter size of about 100 nm.The samples using one-dimensio nal nanometer titanium oxide(TiO2 NB)as the raw material can get a super high initial discharge capacity of 367.8 mAh/g at the rate of C/10 and excellent cycling stability.The selection of raw materials and adopting multi-phase modification can be considered as an effective strategy to improve the electro-chemical properties of Li_(2)FeTiO_(4) composite cathode materials for the lithium secondary battery.

关键词： Li_(2)FeTiO_(4)nanocomposites cathode materials Hydrothermal reaction Lithium ion battery Post-heat-treatment

Electrochemical performance of sulfur composite cathode materials for rechargeable lithium batteries

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Chinese Chemical Letters 2009年第10期20卷 1255-1258页

作者： Feng Wu Sheng Xian Wu Ren Jie Chen Shi Chen Guo Qing Wang School of Chemical Engineering and Environment Beijing Institute of TechnologyBeijing Key Laboratory of Environmental Science and Engineering Beijing 100081 China National Development Center for High Technology Green Material Beijing 100081 China

The structure and characteristic of carbon materials have a direct influence on the electrochemical performance of sulfur-carbon composite electrode materials for lithium-sulfur battery. In this paper, sulfur composite has been synthesized by heating a mixture of elemental sulfur and activated carbon, which is characterized as high specific surface area and microporous structure. The composite, contained 70% sulfur, as cathode in a lithium cell based on organic liquid electrolyte was tested at room temperature. It showed two reduction peaks at 2.05 V and 2.35 V, one oxidation peak at 2.4 V during cyclic voltammogram test. The initial discharge specific capacity was 1180.8 mAh g-1 and the utilization of electrochemically active sulfur was about 70.6% assuming a complete reaction to the product of Li2S. The specific capacity still kept as high as 720.4 mAh g^-1 after 60 cycles retaining 61% of the initial discharge capacity.

关键词： Sulfur composite cathode materials Activated carbon Electrochemical performance

Synthesis and Characterization of LiCo_xMn_(2-x)O_4 cathode materials

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Journal of Wuhan University of Technology(materials Science) 2007年第2期22卷 307-310页

作者：姚耀春 Takayuki Watanabe Faculty of materials and Metallurgy Engineering Kunming University of Science and Technology Department of Environmental Chemistry and Engineering Tokyo Institute of Technology4259 Nagatsuta

LiCoxMn2.04 cathode materials for lithium ion batteries were synthesized by mechanical activation-solid state reaction at 750 ℃ for 24 h in air atmosphere, and their crystal structure, morphology, element composition and electrochemical performance were characterized with XRD, SEM, ICP-AES and charge-discharge test. The experimental results show that all samples have a single spinel structure, well formed crystal shape and uniformly particle size distribution. The lattice parameters of LiCo Mn2-xO4 decrease and the average oxidation states of manganese ions increase with an increase in Co content. Compared with pure LiMn2O4, the LiCo Mn2xO4 （x=0.03-0.12） samples show a lower special capacity, but their cycling life are improved. The capacity loss of LiCo009Mn191O4 and LiCo0.1Mn1.88O4 is only 1.85% and 0.95%, respectively, after the 20th cycle. The improvement of the cycle performance is attributed to the substitution of Co at the Mn sites in the spinel structure, which suppresses the Jahn-Teller distortion and improves the structural stability.

关键词： lithium ion batteries cathode materials spinel LiMn2O4 mechanical activation-solid state method Co-doping

One-pot pyrolysis route to Fe−N-Doped carbon nanosheets with outstanding electrochemical performance as cathode materials for microbial fuel cell

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International Journal of Agricultural and Biological Engineering 2020年第6期13卷 207-214页

作者： Yong Sun Zezhen Zhang Yongming Sun Gaixiu Yang College of Engineering Northeast Agricultural UniversityHarbin 150030China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesCAS Key Laboratory of Renewable EnergyGuangdong Provincial Key Laboratory of New and Renewable Energy Research and DevelopmentGuangzhou 510640China

The naturally lackadaisical kinetics of oxygen reduction reaction(ORR)in the cathode is one of the important factors that restrict the development of air-cathode microbial fuel cells(MFCs).In this work,the iron-nitrogen-carbon hierarchically nanostructured materials had been successfully fabricated by pyrolyzing glucose,iron chloride,and dicyandiamide with the aim of solving the issue.The obtained catalyst with an ultrathin nanostructure demonstrated an idiosyncratic electrocatalytic activity caused by the high content introduction of nitrogen and iron atoms,large surface area,which will offer sufficient active sites for improving the charge/mass transfer and reducing the diffusion resistance.Furthermore,with the increase of N dopant in the catalyst,better ORR catalytic activity could be achieved.Illustrating the N doping was beneficial to the ORR process.The high content of N,BET surface area caused by the N increasing could be responsible for the superior performance according to results of X-Ray photoelectron spectroscopy(XPS),Raman and Brunner-Emmet-Teller(BET)analysis.The ORR on the Fe-N3/C material follows 4e−pathway,and MFCs equipped with Fe-N3/C catalyst achieved a maximum power density(MPD)of 912 mW/m2,which was 1.1 times of the MPD generated by the commercial Pt/C(830 mW/m2).This research not only provided a feasible way for the fabrication of Pt-free catalyst towards oxygen reduction but also proposed potential cathode catalysts for the development of MFCs.

关键词： one-pot pyrolysis route Fe−N-Doped carbon nanosheets microbial fuel cells iron-nitrogen co-doping carbon based catalyst electrochemical performance cathode materials

LiFePO_(4)/C cathode materials synthesized by co-precipitation and microwave heating

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Frontiers of Chemical Science and Engineering 2008年第4期2卷 422-427页

作者： Yunlong XU Lili TAO Hongyan MA Huaqing HUANG Key Laboratory for Ultrafine materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

LiFePO_(4)/C cathode materials were synthesized by a combination of co-precipitation and microwave heat-ing using polyethylene glycol(PEG)as a carbon resource and the influence of microwave heating time on the struc-ture and electrochemical performance of the materials was also discussed.The samples were characterized by X-ray diffraction(XRD),TEM,particle-size analysis and con-stant current charge-discharge experiment.The results show that the LiFePO_(4)/C heated for 9 min has a pure olive-type phase and excellent electrochemical perform-ance.The initial discharge capacities of this sample are 154.3,139.7,123.9 mAh/g at the rates 0.1C,0.2C,1C at room temperature,respectively,and after 20 cycles remain 152.3,134.3,118.5 mAh/g,respectively.

关键词： lithium-ion battery cathode materials LiFePO_(4)/C microwave heating

Empowering the Future: Exploring the Construction and Characteristics of Lithium-Ion Batteries

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Advances in Chemical Engineering and Science 2024年第2期14卷 84-111页

作者： Dan Tshiswaka Dan Belt and Road School Beijing Normal University Zhuhai China

Lithium element has attracted remarkable attraction for energy storage devices, over the past 30 years. Lithium is a light element and exhibits the low atomic number 3, just after hydrogen and helium in the periodic table. The lithium atom has a strong tendency to release one electron and constitute a positive charge, as Li . Initially, lithium metal was employed as a negative electrode, which released electrons. However, it was observed that its structure changed after the repetition of charge-discharge cycles. To remedy this, the cathode mainly consisted of layer metal oxide and olive, e.g., cobalt oxide, LiFePO4, etc., along with some contents of lithium, while the anode was assembled by graphite and silicon, etc. Moreover, the electrolyte was prepared using the lithium salt in a suitable solvent to attain a greater concentration of lithium ions. Owing to the lithium ions’ role, the battery’s name was mentioned as a lithium-ion battery. Herein, the presented work describes the working and operational mechanism of the lithium-ion battery. Further, the lithium-ion batteries’ general view and future prospects have also been elaborated.

关键词： Lithium-Ion Batteries Battery Construction Battery Characteristics Energy Storage Electrochemical Cells Anode materials cathode materials State of Charge (SOC) Depth of Discharge (DOD) Solid Electrolyte Interface (SEI)

Advances in electrocarboxylation reactions with CO_(2)

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Green Carbon 2024年第1期2卷 45-56页

作者： Junjun Mao Yubo Wang Bo Zhang Yang Lou Chengsi Pan Yongf Zhu Ying Zhang Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material EngineeringJiangnan UniversityWuxiJiangsu 214122China School of Physics Peking UniversityBeijing 100091China Department of Chemistry Tsinghua UniversityBeijing 100084China

Recently,significant research has been conducted on the conversion of carbon dioxide(CO_(2))into value-added chemicals.With the decreasing cost of clean electricity,electrochemical methods have emerged as potential approaches for converting and fixing CO_(2).Organic electrochemical synthesis is a promising method for utilizing CO_(2)because it transforms CO_(2)into higher-value chemicals.This review introduces the research aspects of CO_(2)conversion and the mechanisms of CO_(2)organic electrocarboxylation reactions.Recent progress in electrocarboxylation with CO_(2)is discussed,considering organic substrates and cathode types under different reaction mechanisms.Finally,the challenges and prospects in this field are highlighted with the aim of further promoting the fundamental understanding of CO_(2)organic electrocarboxylation.

关键词： CO_(2)conversion Organic electrocarboxylation mechanism Carboxylic acids cathode materials

Research on Preparation and Electrical Properties of cathode materials of La0.8Sr0.2Co0.085CuxFe0.915-xO3-δ for ITSOFC

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Research on Preparation and Electrical Properties of Cathode...

Synthesis and Electrochemical Performances of Nano-particle FePO4 and Ce-doped FePO4 cathode materials for Lithium Ion Batteries by Microemulsion Method

第六届国际稀土开发与应用研讨会

作者： JIE YU~a,WEN-HUI MA~(b*),HUA WANG~b,CHENG-HONG ZOU~a,YA-LEI Du~a [a.Department of Renewable Resources Science and Technology,School of Environment, Science and Engineering,Kunming University of Science and Technology,Kunming,650093 b.Department of Metallurgical Engineering,School of materials and Metallurgical Engineering,Kunming University of Science and Technology,Kunming,650093]

The powders of cathode materials LaSrCoCuFeO(x=0.1,0.3,0.5, 0.7) for ITSOFC were synthesized by the Glycine-Nitrate Process(GNP).XRD were used to characterize the materials.The results show that only the LSCCF(x=0.3) exhibits pure perovskite phase.The other materials exist a small amount of impurity phase.Electrical conductivity was measured by a four-probe DC method.It is found that LSCCF(x=0.1,0.5,0.7) correspond to the small polaron principle at Air atmosphere,the electrical conductivity increasing with the temperature.The electrical conductivity of LSCCF(x=0.3) obeys the small polaron principle at low temperature,while the oxygen vacancy conduction principle at high temperature.Its electrical conductivity increases first and decreases later with the temperature increasing,and reaches the maximum of 1809.47S·cm at 873.15K.On the other hand,the electrical conductivity of LSCCF(x=0.3) has little effect by the temperature in Argon atmosphere and far less than in Air atmosphere.

关键词： ITSOFC cathode materials La0.8Sr0.2Co0.085CuxFe(0.915-xO3-δ Perovskite Conductivity

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Synthesis and Electrochemical Performances of Nano-particle ...