Effect of elemental substitution on the structure and hydrogen storage properties of LaMgNi4 alloy
Effect of elemental substitution on the structure and hydrogen storage properties of LaMgNi4 alloy
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元素替代对LaMgNi4合金结构及储氢性能的影响
DOI：
10.1016/j.matdes.2015.12.150
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发表时间：
2016-03
影响因子：
8.4
通讯作者：
Yanghuan Zhang
中科院分区：
文献类型：
--
作者：
Tai Yang;Zeming Yuan;Wengang Bu;Zhichao Jia;Yan Qi;Yanghuan Zhang
采用感应熔炼法制备了标称式为LaMgNi3.6M0.4（M = Ni, Co, Mn, Cu, Al）的金属间化合物，并对其结构和储氢性能进行了研究。结果表明，合金具有较大的吸氢能力，元素取代对合金的显微组织和储氢性能有显著影响。合金电极的放电容量依次为Co > Ni > Al > Cu > Mn。此外，合金的电化学动力学取决于其显微组织和相组成。晶粒尺寸越小，电化学动力学越好。在第一次加氢过程中，合金的气态氢吸收容量约为1.7 wt.%。加氢和脱氢引起的开裂也显著改善了合金颗粒的吸氢动力学。随着循环次数的增加，合金的储氢能力迅速下降。这一结果归因于氢吸收-解吸循环过程中lamgni4相的非晶化（h2诱导的非晶化）。我们的研究结果为研究La-Mg-Ni系储氢合金的容量退化机制提供了新的见解，可能会提高储氢合金的循环稳定性。
Intermetallic compounds with the nominal formula LaMgNi3.6M0.4(M = Ni, Co, Mn, Cu, Al) were prepared through induction melting, and the structure and hydrogen storage properties of the resultant alloys were extensively investigated. Results showed that the alloys exhibit sizable hydrogen absorption capacity and that elemental substitution significantly influences their microstructure and hydrogen storage properties. The discharge capacities of the alloy electrodes decrease in the order Co > Ni > Al > Cu > Mn. Moreover, the electrochemical kinetics of the alloys depend on their microstructures and phase compositions. Smaller grain size is helpful to improve the electrochemical kinetics. The gaseous hydrogen absorption capacities of the alloys are approximately 1.7 wt.% in the first hydrogenation process. Cracking caused by hydrogenation and dehydrogenation also significantly improves the hydrogen absorption kinetics of the alloy particles. The hydrogen storage capacities of the alloys rapidly decrease with increasing cycle number. This result is attributed to amorphisation of the LaMgNi4phase during hydrogen absorption–desorption cycling (H2-induced amorphisation). Our findings provide new insights into the capacity degradation mechanism of La–Mg–Ni system hydrogen storage alloys that may improve their cycling stability.
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影响因子：
7.2
作者：
Z. Dong;Liqun Ma;Xiao-dong Shen;Limin Wang;Yao-ming Wu;Lidong Wang
通讯作者：
Z. Dong;Liqun Ma;Xiao-dong Shen;Limin Wang;Yao-ming Wu;Lidong Wang
影响因子：
6.2
作者：
Kadir, K;Noréus, D;Yamashita, I
通讯作者：
Yamashita, I
影响因子：
7.2
作者：
Yang-huan Zhang;Dong-liang Zhao;Bao-wei Li;Xiao-long Zhao;Zhong-wang Wu;Xin-lin Wang
通讯作者：
Yang-huan Zhang;Dong-liang Zhao;Bao-wei Li;Xiao-long Zhao;Zhong-wang Wu;Xin-lin Wang
非化学计量对La(Ni3.8Al1.0Mn0.2)x合金储氢性能的影响
影响因子：
7.2
作者：
Wang, P.;Luo, G.;Chen, W.;Chen, D. M.;Yang, K.;Li, S. L.
通讯作者：
Li, S. L.
影响因子：
--
作者：
Liu, Yongfeng;Pan, Hongge;Wang, Qidong
通讯作者：
Wang, Qidong