Effect of annealing treatment on structure and electrochemical properties of La0.67Mg0.33Ni2.5Co0.5 alloy electrodes

doi:10.1016/j.jpowsour.2005.02.031

	Effect of annealing treatment on structure and electrochemical properties of La0.67Mg0.33Ni2.5Co0.5 alloy electrodes
	Zhang, Faliang 2; Luo, Yongchun 1; Chen, Jiangping 2; Yan, Ruxu 2; Kang, Long 2; J., Chen
刊名	Journal of Power Sources
	2005-10-04
卷号	150 期号:1-2 页码:247-254
关键词	Absorption Annealing Desorption Electrochemistry Electrodes Melting Molecular structure Scanning electron microscopy X ray diffraction Alloy structures Electrochemical properties Hydrogen storage alloys Ni/MH batteries
ISSN号	03787753
DOI	10.1016/j.jpowsour.2005.02.031
英文摘要	La0.67Mg0.33Ni2.5Co0.5 alloys were prepared by induction melting followed by different annealing treatments (1023, 1073, 1123 and 1173 K) for 24 h. Alloy structure and electrochemical properties of different annealed alloys have been studied systematically by X-ray diffraction (XRD), scanning electron microscope (SEM) and electrochemical experiments. Alloy structure analyses show that all of the alloys consisted of complex phases such as (La, Mg)(Ni, Co)3 phase (PuNi 3-type, SG: R-3 m), (La, Mg)2(Ni, Co)7 phase (Ce2Ni7-type, SG: P63/mmc), LaMg(Ni, Co) 4 phase (MgCu4Sn-type, SG: F-4 3 m) and La(Ni, Co) 5 phase (CaCu5-type, SG:P6/mmm). One thousand one hundred and twenty-three kelvin benefited formation of (La, Mg)(Ni, Co)3 phase best. Main phase in alloy became (La, Mg)2(Ni, Co)7 phase at 1173 K annealing treatment. Electrochemical experiments show that absorption/desorption plateau became flatter and wider after annealing treatment, that all of the alloy electrodes exhibited good activation characteristics, that annealing treatment improved discharge capacities of alloy electrodes from 315 mAh g-1 (as-cast) to 402.5 mAh g-1 (1173 K). At the same time, cyclic stability of alloy electrodes was also improved with rise of annealing temperature, especially for alloy electrode (S70 = 92.9%) with main phase (La, Mg)2(Ni, Co) 7 at 1173 K. As (La, Mg)(Ni, Co)3 phase in alloys increased, high rate dischargeability characteristics were deteriorated. However, alloy electrode with main phase (La, Mg)2(Ni, Co) 7 exhibited the best kinetic characteristics. All experiments imply that alloy electrode with main phase (La, Mg)2(Ni, Co)7 possessed excellent overall electrochemical properties. © 2005 Elsevier B.V. All rights reserved.
WOS研究方向	Chemistry ; Electrochemistry ; Energy & Fuels ; Materials Science
语种	英语
出版者	Elsevier
WOS记录号	WOS:000232432300027
内容类型	期刊论文
源URL	[http://ir.lut.edu.cn/handle/2XXMBERH/112291]
专题	材料科学与工程学院
作者单位	1.State Key Laboratory of Advanced Non-Ferrous Materials, Lanzhou University of Technology, Lanzhou 730050, China 2.Department of Materials Science and Engineer, Lanzhou University of Technology, Lanzhou 730050, China;
推荐引用方式 GB/T 7714	Zhang, Faliang,Luo, Yongchun,Chen, Jiangping,et al. Effect of annealing treatment on structure and electrochemical properties of La0.67Mg0.33Ni2.5Co0.5 alloy electrodes[J]. Journal of Power Sources,2005,150(1-2):247-254.
APA	Zhang, Faliang,Luo, Yongchun,Chen, Jiangping,Yan, Ruxu,Kang, Long,&J., Chen.(2005).Effect of annealing treatment on structure and electrochemical properties of La0.67Mg0.33Ni2.5Co0.5 alloy electrodes.Journal of Power Sources,150(1-2),247-254.
MLA	Zhang, Faliang,et al."Effect of annealing treatment on structure and electrochemical properties of La0.67Mg0.33Ni2.5Co0.5 alloy electrodes".Journal of Power Sources 150.1-2(2005):247-254.