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Point of Zero Salt Effect: Relationships with Clay Mineralogy of Representative Soils of the So Paulo State, Brazil

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Pedosphere 2005年第5期15卷 545-553页

作者： M. E. ALVES A. LAVORENTI Departamento de Física e Informática Institute de Física de So Carlos-IFSC/USP So Carlos (SP) 13560-970(Brazil). Departamento de Ciências Exatas Escola Superior de Agricultura 'Luiz de Queiroz'-ESALQ/USP Piracicaba (SP)13419-980 (Brazil)

The point of zero salt effect （PZSE） is the soil pH value at which the magnitude of the variable surface charges is not changed due to variations in the ionic concentration of the soil solution. This property influences not only electrochemical phenomena occurring at the solid-solution interface but also the flocculation degree of the soil particles. In this study we investigated the relationships between the clay mineralogy and the PZSE values of representative soils of the Sāo Paulo State, Brazil. The results confirmed the usefulness of the difference between the soil pH values measured in 1 mol L^-1 KCl （pHKCl） and in water （pHH2O）（2 pHKCl-pHH2O） for estimating the PZSE of tropical soils, except for the ones rich in exchangeable Al; furthermore, the ApH index （pHKC1 - pHH2O） was highly correlated with the difference between the PZSE and pHH2O values, reiterating the △pH utility for estimating both the signal and the magnitude of the net surface charge of tropical soils. Finally, correlation and multiple regression analyses showed that the PZSE value of weathered non-allophanic tropical soils tends to increase and to equal the soil pH due to the weathering-induced kaolinite destabilization and concomitant Fe- and Al-oxide accumulation.

关键词： electrochemical properties iron oxides kaolinite tropical soils weathered soils

Growth of HT-LiCoO2 thin films on Pt-metalized silicon substrates

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Rare Metals 2008年第3期27卷 266-272页

作者： ZHANG Yao~(a,b) CHUNG Chiyuen~b ZHU Min~a ~a School of Mechanical Engineering,South China University of Technology,Guangzhou 510640,China ~b Department of Physics and Materials Science,City University of Hong Kong,Hong Kong,China School of Mechanical Engineering South China University of Technology Guangzhou 510640 China Department of Physics and Materials Science City University of Hong Kong Hong Kong China

Layered LiCoO2（HT-LiCoO2）films were grown on Pt-metalized silicon（PMS）substrates and polished bulk nickel（PBN）substrates by pulsed laser *** effects of substrate temperature,oxygen pressure,and substrate surface roughness on the microstructure of LiCoO2 films were *** has been found that a higher substrate temperature and a higher oxygen pressure favor the formation of better crystallized and less lithium-deficient HT-LiCoO2 *** HT-LiCoO2 film deposited on PBN substrates consists of large randomly orientated equiaxial grains,whereas on PMS substrate,it is made up of loosely packed highly[001]preferential orientated triangular shaped grains with the average grain size less than 100 *** measurements show that the highly[001]preferentially orientated nanostructured HT-LiCoO2 thin film grown on PMS substrate has good structural stability upon lithium insertion/extraction and can deliver an initial discharge capacity of approximately 45μA·h·cm-2·μm-1with a cycling efficiency of above 99% at the charge/discharge rate of 0.5 C.

关键词： thin film LiCoO2 pulsed laser deposition electrochemical properties thin film growth

Enhanced Capacitive Desalination Performance of Porous Carbon Spheres@MnO2 Composite

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Chinese Journal of Chemistry 2017年第1期35卷 55-60页

作者： Bingwei Chen Yanfang Wang Feng Yu Yusong Zhu Lixin Zhang Yuping Wu New Energy and Material Laboratory (NEML) Department of Chemistry & Shanghai Key Laboratory of Molecular Catalysis and lnnovative Material Fudan University Shanghai 200433 China College of Energy and Institute for electrochemical Energy Storage Nanjing Tech University Nanjing Jiangsu 211816 China

A porous carbon spheres@MnO2 composite is prepared and used as the electrosorption electrode. The MnO2 nanoparticles are evenly distributed on the porous carbon spheres. The as-prepared composite possesses high specific surface area of 258.6 m2·g -1. Its electrochemical evaluations confirm that the composite has high specific capacitance of 175 Fog-1 at a current density of 1 A·g -1 in 0.5 mol·L-1 NaC1 aqueous solution, and shows good conductivity and excellent cycling performance. Electrosorption capacity for the porous carbon spheres@MnO2 composite is 6.28 mg·g-1. Moreover, the composite electrode exhibits excellent recyclability with an efficient regeneration process.

关键词： carbon nanostructure composite electrochemical properties desalination performance

Influence of Sintering Temperature on the Structure and High-temperature Discharge Performance of Li Ni_(1/3)Mn_(1/3)Co_(1/3)O_2 Cathode Materials

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Journal of Wuhan University of Technology(Materials Science) 2015年第5期30卷 894-899页

作者：王振杰 DU Junlin LI Zhilin 吴铸 Research Center for New Energy Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences University of Chinese Academy of Sciences

Layered cathode materials of high-temperature lithium batteries, Li Ni1/3Mn1/3Co1/3O2 are synthesized by a sol-gel method with variation in final sintering temperature for borehole applications. The structure, morphology and high-temperature discharge performance of these resulting products are investigated by X-Ray Diffraction(XRD), scanning electron microscopy(SEM), laser particle size analysis, galvanostatic and pulse discharge. The results of structural analysis indicate that the sample sintered at 800 ℃ has the characteristics of good crystallinity, narrow size distribution and large specific surface area at the same time. The discharge experiments also indicate that this sample has the best electrochemical properties, with the maximum discharge capacities of 314.57 and 434.14 m Ah·g-1 at 200 and 300 ℃ respectively and the minimum cell internal resistances at both temperatures.

关键词： sintering temperature electrochemical properties Li Ni1/3Mn1/3Co1/3O2 high-temperature lithium batteries

Preparation and electrochemical characterization of C/PANI composite electrode materials

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Journal of Central South University of Technology 2006年第4期13卷 353-359页

作者：赖延清李晶李劼卢海张治安刘业翔 School of Metallurgical Science and Engineering Central South University

Taking the nano-sized carbon black and aniline monomer as precursor and （NH4）2S2O6 as oxidant, the well coated C/polyaniline（C/PANI） composite materials were prepared by in situ polymerization of the aniline on the surface of well-dispersed nano-sized carbon black for supercapacitor. The micro-structure of the C/PANI composite electrode materials were analyzed by SEM. The electrochemical properties of C/ PANI and PANI composite electrode were characterized by means of the galvanostatic charge-discharge experiment, cyclic voltammetric measurement and impedance spectroscopy analysis. The results show that by adding the nano-sized carbon black in the process of chemical polymerization of the aniline, the polyaniline can be in situ polymerized and well-coated onto the carbon black particles, which may effectively improve the aggregation of particles and the electrolyte penetration. What’s more , the maximum of specific capacitance of C/PANI electrode 437.6F·g -1 can be attained. Compared with PANI electrode, C/PANI electrode shows more desired capacitance characteristics, smaller internal resistance and better cycle performance.

关键词： supercapacitor polyaniline composite electrode materials electrochemical properties

An Approach towards Synthesis of Nanoarchitectured LiNi1/3Co1/3Mn1/3O2 Cathode Material for Lithium Ion Batteries

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中国化学:英文版 2015年第2期33卷 261-267页

作者： Weibo Hua Yanjie Wang Yanjun Zhong Guoping Wang Benhe Zhong Baizeng Fang Xiaodong Guo Shixuan Liao Haijiang Wang College of Chemical Engineering Sichuan UniversityChengduSichuan 610065China Department of Chemical and Biological Engineering University of British Columbia2360 East MallVancouverBCCanadaV6T 1Z3 Institute for Fuel Cell Innovation National Research Council of Canada4250 Wesbrook MallVancouverBC V6T 1W5Canada College of Chemical Engineering University of South ChinaHengyangHunan 421001China

To explore advanced cathode materials for lithium ion batteries(LIBs),a nanoarchitectured LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2)(LNCM)material is developed using a modified carbonate coprecipitation method in combination with a vacuum distillation-crystallisation *** with the LNCM materials produced by a traditional carbonate copre-cipitation method,the prepared LNCM material synthesized through this modified method reveals a better hexago-nal layered structure,smaller particle sizes(ca.110.5 nm),and higher specific surface *** of its unique structural characteristics,the as-prepared LNCM material demonstrates excellent electrochemical properties in-cluding high rate capability and good cycleability when it is utilized as a cathode in the lithium ion battery(LIB).

关键词： cathode materials nanoarchitectured coprecipitation electrochemical properties lithium ion battery

1,3-Dipolar cycloaddition reaction of two different azomethine ylides to C70

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Chinese Journal of Chemistry 1998年第2期16卷 178-183页

作者：郑大贵李玉良范楼珍李凤英李永舫朱道本 nstitute of Chemistry Chinese Academy of SciencesBeijing 100080ChinaShangrao Teacher's CollegeShangraoJiangzi 334001China nstitute of Chemistry Chinese Academy of SciencesBeijing 100080China

1,3-Dipolar cycloaddition to C70 of an azomethine ylide, which was generated in situ from refluxing a mixture of cyclohexanone and DL-valine in chlorobenzene under N2, afforded a monoadduct and a bisadduct. Even for longer reaction time, however, only monoadduct waa obtained from the reaction of C70 with an azomethine ylide generated from refluxing a mixture of 2-undecanone and 2-aminoisobutyric acid in chlorobenzene under N2. The electrochemical properties of all the products were studied by cyclic voltammetry.

关键词： Fullerenes 1,3-dipolar cycloaddition azomethine electrochemical properties

electrochemical capacity fading of polyaniline electrode in supercapacitor:An XPS analysis

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Progress in Natural Science:Materials International 2017年第2期27卷 257-260页

作者： Jinxing Deng Tingmei Wang Jinshan Guo Peng Liu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences

To understand the electrochemical capacity fading of the polyaniline（PANI） electrodes in supercapacitors, for the first time, their chemical structure change during electrochemical cycles was traced with XPS analysis after the HCl doped PANI electrodes were subjected to the cyclic voltammetry test in 1.0 M H;SO;electrolyte for different cycle numbers. The results showed that the chlorine disappeared in the electrode surface, while the surface element contents of sulfur and oxygen increased with the electrochemical cycles increased. It demonstrated that the hydrolytic degradation of the PANI chains and exchange of dopant occurred during the electrochemical cycling, causing the fading in the mechanical and electrochemical performance of the PANI electrodes. This understanding should lead to better design of the conductive polymer-based energy storage devices.

关键词： Polyaniline electrochemical properties Fading XPS analysis

An Improved Method for Synthesizing LiV3O8 Nanorods

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Chinese Journal of Chemistry 2012年第4期30卷 900-904页

作者：孙均利赵敏 Scientific Research Institution Scientific Research DepartmentChinese People's Armed Police Forces Academy220 Xihuan RoadAnci DistrictLangfang CityHebei 065000China

This paper reports on the synthesis, characterization and electrochemical performance of LiV3O8 nanorods which were prepared through a very facile hydrothermal route. The diameters of the LiV3O8 nanorods are about 150 nm. The morphology of LiV3O8 can be controlled by adjusting the reaction conditions such as the reaction time and temperature. electrochemical measurements reveal that the as-prepared LiV3O8 nanorods display high initial dis- charge capacities （292.5 mAohg-1 ） and excellent cyclability. This result indicates that the nanorods are a promising cathode candidate material for lithium batteries.

关键词： electrochemical properties nano structures SEM TEM cathode materials