The as-cast RE-Mg-Ni-b ased AB2-type La1-xPrxMgNi3.6Co0.4(x=0-0.4)alloys were prepared by vacuum induction melting followed by annealing treatment.The phase composition and structure were characterized by X-ray diffra...The as-cast RE-Mg-Ni-b ased AB2-type La1-xPrxMgNi3.6Co0.4(x=0-0.4)alloys were prepared by vacuum induction melting followed by annealing treatment.The phase composition and structure were characterized by X-ray diffraction(XRD)and scanning electron microscope(SEM).The results show that LaMgNi4 and LaNi5 coexist in as-cast alloys,but only LaMgNi4 is detected in the annealed alloys.The morphology of annealed alloys is more homogeneous than that of as-cast alloys.The gaseous hydrogen storage and electrochemical properties were investigated by pressure-composition isotherm(P-C-T)and electrochemical measurements.The P-C-T curves of annealed alloys show flatter and wider pressure plateaus corresponding to absorption/desorption pressure plateaus of LaMgNi4 hydride.But the maximum hydrogen storage content of annealed alloys is lower than that of as-cast alloys.In consideration of the electrochemical properties,the annealed La0.8Pr0.2MgNi3.6Co0.4alloy exhibits a maximum discharge capacity of354.2 mAh·g-1.展开更多
基金Projects(10JC407700,11ZR1417600) supported by the Science and Technology Committee of Shanghai,ChinaProject(12ZZ017) supported by the Shanghai Education Commission,China
基金financially supported by the National Natural Science Foundations of China(Nos.51161015 and 51371094)the Natural Science Foundation of Inner Mongolia, China (No. 2011ZD10)
文摘The as-cast RE-Mg-Ni-b ased AB2-type La1-xPrxMgNi3.6Co0.4(x=0-0.4)alloys were prepared by vacuum induction melting followed by annealing treatment.The phase composition and structure were characterized by X-ray diffraction(XRD)and scanning electron microscope(SEM).The results show that LaMgNi4 and LaNi5 coexist in as-cast alloys,but only LaMgNi4 is detected in the annealed alloys.The morphology of annealed alloys is more homogeneous than that of as-cast alloys.The gaseous hydrogen storage and electrochemical properties were investigated by pressure-composition isotherm(P-C-T)and electrochemical measurements.The P-C-T curves of annealed alloys show flatter and wider pressure plateaus corresponding to absorption/desorption pressure plateaus of LaMgNi4 hydride.But the maximum hydrogen storage content of annealed alloys is lower than that of as-cast alloys.In consideration of the electrochemical properties,the annealed La0.8Pr0.2MgNi3.6Co0.4alloy exhibits a maximum discharge capacity of354.2 mAh·g-1.
