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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.
LaMg8.52Ni2.23M0.15 (M = Ni, Cu, Cr) alloys were prepared by induction melting. X-ray analysis showed that all the three alloys had a multiphase structure, consisting of La2Mg17, LaMg2Ni and Mg2Ni phases. -ray spectrometer results revealed that most of Cu and Cr distributed in Mg2Ni phase. La2Mg17 and LaMg2Ni phases were decomposed into MgH2, Mg2NiH4 and LaH3 phases during the hydrogenation process. Hydriding / dehydriding measurements indicated the reversible hydrogen storage capacities of Mg2Ni phase in LaMg8. % Of 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 (M = Cu, Cr) alloys increased to 1.05 wt. 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 Mg2 NiH4 phase.