Effect of annealing temperature on microstructures and electrochemical performances of La0.75Mg0.25Ni3.05Co0.2Al0.1Mo0.15 hydrogen storage alloy
Effect of annealing temperature on microstructures and electrochemical performances of La0.75Mg0.25Ni3.05Co0.2Al0.1Mo0.15 hydrogen storage alloy
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退火温度对La0.75Mg0.25Ni3.05Co0.2Al0.1Mo0.15储氢合金显微组织和电化学性能的影响
DOI：
10.1016/j.ijhydene.2016.02.133
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发表时间：
2016-07
影响因子：
7.2
通讯作者：
Ying Wu
中科院分区：
文献类型：
--
作者：
Wei Li;Bao Zhang;Jianguang Yuan;Ying Wu
研究了退火温度对La0.75Mg0.25Ni3.05Co0.2Al0.1Mo0.15贮氢合金组织和电化学性能的影响。通过真空感应熔炼制备合金，然后分别在1073、1123、1173和1223 K下退火处理8 h。铸态和退火态合金中的主要相为（La，Mg）2Ni 7、（La，Mg）5 Ni 19和LaNi 5相，铸态合金中的残余相MoNi 4经热处理后分解为Mo相。退火处理有利于LaNi 5相向（La，Mg）2Ni 7和（La，Mg）5 Ni 19相的转变，但随着退火温度的升高，这种转变趋势受到抑制。退火态合金的相分布更均匀，结晶更好。电化学实验表明，退火处理有利于提高合金电极的最大放电容量，但降低了合金电极的活化能力。在1073-1173 K退火处理使合金的相分布均匀，从而延长了合金的循环寿命。然而，退火处理明显降低了合金电极的动力学性能，这主要归因于具有高效电催化活性的MoNi 4相的消失。合金在1173 K退火后的综合电化学性能在上级放电容量、动力学性能和循环稳定性的显著改善之间呈现出良好的平衡。
The effect of annealing temperature on microstructures and electrochemical performances of La0.75Mg0.25Ni3.05Co0.2Al0.1Mo0.15hydrogen storage alloy is investigated. The alloys was prepared via vacuum induction melting followed by annealing treatment for 8 h at the temperatures of 1073, 1123, 1173, and 1223 K, respectively. The major phases in the as-cast and annealed alloys are consisted of (La, Mg)2Ni7, (La, Mg)5Ni19and LaNi5phase while the residual phase MoNi4existing in the as-cast alloy decomposes into Mo phase after heat treatment. Annealing treatment facilitates LaNi5phase transforms into (La, Mg)2Ni7and (La, Mg)5Ni19phase, but the tendency is suppressed as annealing temperature increases. Furthermore, the annealed alloys have more homogeneous phase distribution and better crystallization. Electrochemical experiments manifest that annealing treatment is beneficial for the increase of the maximum discharge capacity while impairs the activation ability of the alloy electrodes. The cycle life is prolonged in consequence of the homogeneous phase distribution created by annealing treatment at 1073–1173 K. Nonetheless, annealing treatment distinctly deteriorates the kinetic property of the alloys electrodes which is mainly ascribed to the disappearance of MoNi4phase with high-efficiency electrocatalytic activity. The comprehensive electrochemical properties of the annealed alloy at 1173 K presents a good balance between superior discharge capacity, kinetic property and remarkably improved cyclic stability.
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影响因子：
7.2
作者：
Jingjing Liu;Shumin Han;Yuan Li;Xin Zhao;Shu-qin Yang;Yumeng Zhao
通讯作者：
Jingjing Liu;Shumin Han;Yuan Li;Xin Zhao;Shu-qin Yang;Yumeng Zhao
粉末烧结LaNi5和LaMgNi4 La-Mg-Ni基复相合金的形成机理、相结构及电化学性能
影响因子：
7.2
作者：
Jingjing Liu;Junling Zhang;Jinding Wang;Shuqin Yang
通讯作者：
Shuqin Yang
影响因子：
9.2
作者：
K. Young;T. Ouchi;Baoquan Huang
通讯作者：
K. Young;T. Ouchi;Baoquan Huang
影响因子：
3.7
作者：
Qingan Zhang;M. Fang;T. Si;Fang Fang-Fang;Dalin Sun;L. Ouyang;Min Zhu
通讯作者：
Qingan Zhang;M. Fang;T. Si;Fang Fang-Fang;Dalin Sun;L. Ouyang;Min Zhu
影响因子：
6.2
作者：
Yang-huan Zhang;Bao-wei Li;H. Ren;Y. Cai;Xiaoping Dong;Xin-lin Wang
通讯作者：
Yang-huan Zhang;Bao-wei Li;H. Ren;Y. Cai;Xiaoping Dong;Xin-lin Wang