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Journal of Rare Earths 2006年第S2期 151-155页

作者：伊廷锋胡信国 Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Department of Applied Chemistry Harbin Institute of Technology

Powders of spinel LiMn2O4 and its substituted forms LiM0.05Mn1.95O4 (M=Al and La) were successfully synthesized by sol-gel method. The effect of Al and La substitution on the powder properties of spinel lithium manganese oxides was examined XRD, SEM and CV. All the samples exhibit a pure cubic spinel structure without any impurities in the XRD patterns. SEM shows that all of the prepared powders have the uniform and narrow size distribution. The powder electrochemical properties of lithium manganese oxide such as discharge capacity, coulomb efficiency (discharge capacity/charge capacity), cycle performance and CV characteristic are strongly affected by substituted metal M (=Al, La) in LiM0.05Mn1.95O4. Pure LiMn2O4 has the highest initial discharge capacity and the lowest capacity retention and coulomb efficiency, and LiMn1.95La0.05O4 is contrary, and the performance of LiMn1.95Al0.05O4 is intervenient between pure LiMn2O4 and LiMn1.95La0.05O4. CV curve implies that LiMn1.95La0.05O4 has the best reversibility.

关键词： lithium ion battery cathode material LiM0.05Mn1.95O4 (M=Mn, Al and La) electrochemical properties rare earths

Oleic acid-treated synthesis of MnO@C with superior electrochemical properties

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Journal of Energy Chemistry 2017年第3期26卷 340-345页

作者： Jing Guo Jiaojiao Liang Chunyu Cui Jianmin Ma Schcool of Physics and Electronics Hunan UniversityChangsha 410082HunanChina

MnO@C nanocomposites are synthesized by annealing MnO microspheres treated with oleic acid as carbon source. The obtained MnO@C nanocomposites exhibit a discharge capacity of 1075 m Ah/g for the initial cycle, and show the excellent cycling performance with a discharge capacity of 421 mAh/g after100 cycles at a current density of 100 mA/g. The total specific capacity of MnO@C nanocomposites is higher than those of pure MnO microspheres in our experiments. Owing to the superior electrochemical behavior, the as-obtained MnO@C nanocomposites are potentially applied as next-generation anode material for lithium-ion batteries.

关键词： MnO Anode Lithium-ion battery Carbon coating electrochemical properties

Influence of magnesium content on structure and electrochemical properties of La_(1-x)Mg_xNi_(1.75)Co_(2.05) hydrogen storage alloys

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Journal of Rare Earths 2016年第12期34卷 1235-1240页

作者：蔡鑫魏范松胥小丽张玉 School of Materials Science and Engineering Jiangsu University of Science and Technology

La（1-x）MgxNi（1.75）Co（2.05）（x=0.07, 0.08, 0.10, 0.13, 0.15） alloys were prepared by high-frequency inductive method, and then their structure and electrochemical properties were investigated systematically. The XRD analysis revealed that the alloys consisted of LaNi5 phase and La4MgNi（19）（Ce5Co（19）＋ Pr5Co（19）） phase, and the introduction of Mg could promote the formation of La4MgNi（19） phase. The observation of microstructure showed that all the alloys processed dendritic structure, which was refined with the increase of x value. The electrochemical measurements showed that all the alloys could be activated within 2 cycles, and with increasing x, the maximum discharge capacity obviously increased from 254.00 m Ah/g（x=0.07） to 351.51 mAh/g（x=0.15）, but the cycling stability（S（80）） decreased somehow from 78.4% to 73.9%. Meanwhile, the appropriate addition of Mg could improve the high-rate discharge capacity（HRD） of the alloy electrodes, which was mainly controlled by the electrochemical reaction rate on the surface of the alloys.

关键词： A5B19-type hydrogen storage alloy phase structure electrochemical properties rare earths

STABILITY AND electrochemical properties OF FULL-CONJUGATED SELF-ASSEMBLED FILMS BASED ON POLYANILINE AND ITS ACID-SUBSTITUTED DERIVATES

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Chinese Journal of Polymer Science 2010年第3期28卷 331-336页

作者：董宇平 College of Chemical Engineering & Materials Science Beijing Institute of Technology

The stability of full-conjugated self-assembled （SA） multilayer films based on partially doped polyaniline （PANI） as a polycation and poly（o-aminobenzoic acid）（PCAN）, poly（aniline-2-sulfonic acid）（PSAN） as polyanions is investigated in alkali aqueous solutions. The self-assembled PANI-PCAN films keep their stability within 24 h in 1 mol/L NaOH solution,-the PANI-PSAN films, however, maintain the stability for 20 min in the same condition because the solubility of PSAN in alkali solutions is much higher than that of PCAN. The electrochemical properties of the SA films are determined, and the film-CdS composites formed in situ are also reported.

关键词： Polyanilines Self-assembly multilayer films electrochemical properties Film-CdS composites

Interconnected Ni(OH)_(2)and polyether amine on carbon fiber surface for simultaneously improving interfacial adhesion of epoxy composites and electrochemical properties

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Chinese Journal of Aeronautics 2022年第5期35卷 419-428页

作者： Qing WU Qinqin WAN Qianli LIU Fen WANG Xin LIU Jianfeng ZHU School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science&TechnologyXi’an 710021China Shanghai Composites Science&Technology Co. Ltd.Shanghai 201112China

Interconnected Ni(OH)_(2)nanoflakes and polyether amine(PEA)were deposited on carbon fiber tows via a facial and effective process of chemical bath deposition and dip *** on this,a win–win benefit of simultaneously improvements in interfacial shear strength(IFSS)of carbon fiber/epoxy composites and the electrochemical activity has been *** with CF and CF-Ni(OH)_(2)composites,the IFSS of CF-Ni(OH)_(2)-PEA/epoxy composite respectively increased 7.9%and 45.4%,which was put down to the covalent bonding of Ni(OH)_(2)-PEA coating with fiber and epoxy matrix,as well as the effective stress transfer by the uniform honeycomb structure of Ni(OH)_(2).In aqueous KOH electrolyte,the CF-Ni(OH)_(2)-PEA electrode presented the maximum specific capacitance of 689.98 F·g^(-1)at 5 m V·s^(-1),572.28 F·g^(-1)at a current density of 0.5 A·g^(-1)due to the strong adhesion of carbon fiber with Ni(OH)_(2)by PEA,the reservation of the threedimensional hollow honeycomb structure of Ni(OH)_(2)for easy ion-transport and–NH_(2)functional groups from PEA for providing more active *** excellent performance of CF-Ni(OH)_(2)-PEA reinforcement demonstrates its promising potential for application in high performance composites with integrated structure and function,which shows great advantages in various fields of aerospace,energy,electronics,automobile,civil engineering,sports,etc.

关键词： Carbon fiber electrochemical properties Interface/interphase Polymer-matrix composites Surface modification

Chevrel phase: A review of its crystal structure and electrochemical properties

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Progress in Natural Science:Materials International 2023年第1期33卷 8-15页

作者： Meng Liu Guocheng Lv Tianming Liu Hao Liu Lingchang Kong Lintao Tian Wenxiu Rao Yuxin Li Libing Liao Juchen Guo Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences(Beijing) School of Science China University of Geosciences Materials Science and Engineering Program University of California-Riverside Department of Chemical and Environmental Engineering University of California – Riverside

Chevrel phase compounds have attracted increasing attention as electrochemical energy storage materials and electro-catalysts. Benefiting from their unique crystal structure, Chevrel phase compounds can not only function as the host structures for reversible intercalation of a broad range of cations, but also exhibit high catalytic activity in electrochemical reduction reactions. Here we provide an overview of recent progress in the development of Chevrel phase materials including new understanding of structural features, synthetic methods, and electrochemical properties. A brief conclusion and perspectives on the future development of Chevrel phase materials are also provided.

关键词： Chevrel phase electrochemical properties Energy storage Electro-catalysis

Effect of Rare Earth Elements on Structure and electrochemical properties of PuNi_3-type Hydrogen Storage Alloys

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Journal of Rare Earths 2005年第S1期23卷 343-349页

作者：张法亮罗永春阎汝煦陈剑虹 Department of Materials Science and Engineering Lanzhou University of Technology Lanzhou 730050 Key Laboratory of advanced Nonferrous Metal Materials Lanzhou University of Technology Lanzhou 730050

Structure and electrochemical properties of (La, Ce, Pr, Nd)_2MgNi_9 hydrogen storage alloys were investigated through orthogonal design experiments, and the alloys were obtained through induction melting followed by annealing treatment. The structure of main phase in alloys belongs to PuNi_3-type with a space group R3m. Rare earth elements, as a substitute of lanthanum, have a significant effect on phase structure of alloys, elements of cerium and neodymium are beneficial to the formation of Gd_2Co_7-type phase with a space group P 6_3/mmc. Rare earth elements can decrease the unit cell volume of main phase of alloys dramatically, and increase the axis ratio. The results of electrochemical experiment showed that the discharge capacity of alloy electrodes ranged from 342.97 to 380.68 mAh·g -1, and elements of cerium and neodymium can reduce the discharge capacity of alloy electrodes significantly. Compared to the electrode of La_2MgNi_9 alloy, the substitution of lanthanum by rare earth elements did not improve the cyclic stability of alloy electrodes due to the anisotropic structure change of unit cell. While rare-earth elements can improve the high rate dischargeability of alloy electrodes, the high rate dischargeability of alloy electrodes could reach the maximum when the unit cell volume of PuNi_3-type structure was about 0532 nm.

关键词： hydrogen storage alloy PuNi_3-type crystal structure electrochemical properties orthogonal experiment design

Effect of AB_(2-)based alloy addition on structure and electrochemical properties of La_(0.5)Pr-(0.2)Zr_(0.1)Mg_(0.2)Ni_(2.75)Co_(0.45)Fe_(0.1)Al_(0.2) hydrogen storage alloy

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Journal of Rare Earths 2013年第4期31卷 386-394页

作者：卢照覃铭蒋卫卿卿培林刘淑辉 Department of Physics and Electronic Engineering Baise University College of Physics Science and Technology Guangxi University

TheLa0.5Pr0.2Zr0.1Mg0.2Ni2.75Co0.45Fe0.1Al0.2（M0 and Zr0.65Ti0.35（Mn0.2V0.2Cr0.15Ni0.45）l.76 （M2） hydrogen storage alloys were prepared by inductive melting. In addition, the M1＋30 wt.%M2 composites were successively prepared by using high-energy ball milling technology. From the X-ray diffraction （XRD） analysis, it was found that M1 and M2 alloys still retained their respective main phases in the MI＋30 wt.%M2 composites. The scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS） indicated that the decrease in discharge capacity of MI and M2 alloy electrodes was ascribed to the oxidation-dissolution of La, Pr, Mg and Ti, Mn, V, Cr active elements, respectively. The electrochemical studies showed that the M1＋30 wt.%M2 composite electrode ball milling for 5 rain exhibited excellence cyclic stability （92.3%） after 80 charge/discharge cycles, which was higher than 77.7 % and 85.6% of MI and M2 alloy electrodes, respectively. Moreover, at the discharge current density of 1200 mA/g, the high rate dis- charge ability （HRD） of the M1＋30 wt.%M2 composite electrode increased from 61.5% （5 rain） to 70.3% （10 rain）. According to the linear polarization, Tafel polarization and cyclic voltammograms （CV）, the electrochemical kinetics of hydrogen reaction on the sur- face of the electrode and hydrogen diffusion rate in the bulk of alloy were also improved in the ML＋30 wt.%M2composite with in- creasing ball milling time.

关键词： La-Mg-Ni-based alloy Zr-based alloy electrochemical properties rare earths

Intelligently assembly of W_(18)O_(49)nanorod clusters with directionally generated oxygen vacancies and excellent electrochemical properties

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Nano Research 2022年第4期15卷 3575-3586页

作者： Dan Zhou Xiaojiao Guo Yixiang Chen Xiaoyu Yuan Jinku Liu Key Laboratory for Advanced Materials School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Mixed-valence metallic compounds are a class of functional materials with peculiar electrochemical *** the correlation between defects and corrosion resistance of mixed-valence metallic compounds is a novel and interesting *** an intelligently designed synergistic process of reduction and directed assembly,not only the directional generation of oxygen vacancies along the normal direction of the(010)crystal plane was achieved,but also the W_(18)O_(49)mixed-valence metal oxide(MVMO)with a single crystalline phase and an assembled ordered three-dimensional cluster structure of nanorods was *** attractive effects of oriented oxygen vacancies in W_(18)O_(49)MVMO were ***,the oxygen vacancy channels realized the directional concentrated transport of oxygen atoms to form dense oxide passivation ***,the directional concentrated oxygen vacancies as active centers effectively solved the problem of difficult photoelectron leap and separation of pure-phase semiconductors,realizing photogenerated cathodic ***,the high-energy vacancies endowed the material with antibacterial function,which contributed to the stable existence of the anti-corrosion *** resistance value of W_(18)O_(49)MVMO as an anti-corrosion functional material was increased to more than 4.00 times that of the original metal protection *** experimental results obtained in this research were of great reference value for revealing the intrinsic mechanism of correlation between oxygen defect orientation of MVMOs and electrochemistry.

关键词： oxygen vacancy directional generated W_(18)O_(49) mixed-valence metal oxide electrochemical properties

Synthesis and electrochemical properties of LiNi_(0.8)Al_(0.2-x)Ti_xO_2 cathode materials by an ultrasonic-assisted co-precipitation method

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 452-457页

作者： Meng Chen Wen-le Ao Chang-song Dai Tao Tao Jun Yang College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 15001 China

A new co-precipitation route was proposed to synthesize LiNi0.8A10.2-xTixO2 （x=0.0-0.20） cathode materials for lithium ion batteries, with Ni（NO3）2, Al（NO3）3, LiOH·H2O, and TiO2 as the starting materials. Ultrasonic vibration was used during preparing the precursors, and the precursors were protected by absolute ethanol before calcination in the air. The influences of doped-Ti content, calcination temperature and time, additional Li content, and ultrasonic vibration on the structure and properties of LiNi0.8A10.2-xTixO2 were investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and charge-discharge tests, respectively. The results show that the optimal molar fraction of Ti, calcination temperature and time, and additional molar fraction of Li for LiNi0.8A10.2-xTixO2 cathode materials are 0.1,700℃, 20 h, and 0.05, respectively. Ti doping facilitates the formation of the α-NaFeO2 layered structure, and ultrasonic vibration improves the electrochemical performance of LiNi0.8A10.2-xTixO2.

关键词： lithium ion batteries cathode materials ultrasonic vibration co-precipitation electrochemical properties