Investigations on hydrogen storage properties of LaMg8.52Ni2.23M0.15 (M=Ni, Cu, Cr) alloys
Investigations on hydrogen storage properties of LaMg8.52Ni2.23M0.15 (M=Ni, Cu, Cr) alloys
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DOI：
10.1016/s1002-0721(12)60239-7
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发表时间：
2013-01-01
影响因子：
4.9
通讯作者：
Liu Baozhong
中科院分区：
文献类型：
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作者：
Shi He;Han Shumin;Liu Baozhong
LaMg8.52Ni2.23M0.15（M=Ni、Cu、Cr）合金通过感应熔炼制备。X射线衍射分析表明，3种合金均为多相结构，均由La2Mg17、LaMg2Ni和Mg2Ni相组成。X射线能谱分析表明，Cu和Cr主要分布在Mg2Ni相中。La2Mg17和LaMg2Ni相在加氢过程中分解为MgH2、Mg2NiH4和LaH3相。吸放氢性能测试表明，Mg2Ni相的可逆贮氢容量提高到1.05wt.%，LaMg8.52Ni2.23M0.15和0.97重量%从0.79重量%在523 K时，LaMg8.52Ni2.38合金中Mg2Ni相的析出速率最大。Cu和Cr部分替代Ni使合金的脱氢起始温度降低，分别降低了18.20和5.50 K。Cu和Cr降低了Mg_2NiH_4相的稳定性，从而提高了合金的脱氢性能。
LaMg8.52Ni2.23M0.15 (M=Ni, Cu, Cr) alloys were prepared by induction melting. X-ray diffraction showed that all the three alloys had a multiphase structure, consisting of La2Mg17, LaMg2Ni and Mg2Ni phases. Energy dispersive X-ray spectrometer results revealed that most of Cu and Cr distributed in Mg2Ni phase. La2Mg17 and LaMg2Ni phases decomposed into MgH2, Mg2NiH4 and LaH3 phases during the hydrogenation process. Hydriding/dehydriding measurements indicated that the reversible hydrogen storage capacities of Mg2Ni phase in LaMg8.52Ni2.23M0.15 (M=Cu, Cr) alloys increased to 1.05 wt.% and 0.97 wt.% from 0.79 wt.% of Mg2Ni phase in LaMg8.52Ni2.38 alloy at 523 K. Partial substitution of Cu and Cr for Ni decreased the onset dehydrogenation temperature of the alloy hydrides and the temperature lowered by 18.20 and 5.50 K, respectively. The improvement in the dehydrogenation property of the alloys was attributed to that Cu and Cr decreased the stability of Mg2NiH4 phase.