The La-Mg-Ni system PuNi3-type La0.5Ce0.2Mg0.3Co0.4Ni2.6-xMnx(x=0,0.1,0.2,0.3,0.4) hydrogen storage alloys were prepared by casting and rapid quenching. The effects of the rapid quenching on the structure and electroc...The La-Mg-Ni system PuNi3-type La0.5Ce0.2Mg0.3Co0.4Ni2.6-xMnx(x=0,0.1,0.2,0.3,0.4) hydrogen storage alloys were prepared by casting and rapid quenching. The effects of the rapid quenching on the structure and electrochemical characteristics of the alloys were studied. The results obtained by XRD,SEM and TEM indicate that the as-cast and quenched alloys mainly consist of two major phases,(La,Mg)Ni3 and LaNi5,as well as a residual phase LaNi. The rapid quenching does not exert an obvious influence on the phase composition of the alloys,but it leads to an increase of the LaNi5 phase and a decrease of the(La,Mg)Ni3 phase. The as-quenched alloys have a nano-crystalline structure,and the grain sizes of the alloys are in the range of 20-30 nm. The results by the electrochemical measurements indicate that both the discharge capacity and the high rate discharge(HRD) ability of the alloy first increase and then decrease with the variety of quenching rate and obtain the maximum values at the special quenching rate which is changeable with the variety of Mn content. The rapid quenching significantly improves the cycle stabilities of the alloys,but it slightly impairs the activation capabilities of the alloys.展开更多
基金supported by the National Key R&D Program of China(2020YFB1505802)Ministry of Science and Technology of China(2017YFA0208200)+2 种基金the National Natural Science Foundation of China(22025108,U21A20327,and 22121001)Guangdong Provincial Natural Science Fund for Distinguished Yong Scholars(2021B1515020081)start-up support from Xiamen University。
基金Project(2006AA05Z132) supported by the Hi-tech Research and Development Program of ChinaProject(50701011) supported by the National Natural Science Foundation of China+1 种基金Project(200711020703) supported by the Natural Science Foundation of Inner Mongolia, ChinaProject(NJzy08071) supported by Higher Education Science Research Project of Inner Mongolia, China
文摘The La-Mg-Ni system PuNi3-type La0.5Ce0.2Mg0.3Co0.4Ni2.6-xMnx(x=0,0.1,0.2,0.3,0.4) hydrogen storage alloys were prepared by casting and rapid quenching. The effects of the rapid quenching on the structure and electrochemical characteristics of the alloys were studied. The results obtained by XRD,SEM and TEM indicate that the as-cast and quenched alloys mainly consist of two major phases,(La,Mg)Ni3 and LaNi5,as well as a residual phase LaNi. The rapid quenching does not exert an obvious influence on the phase composition of the alloys,but it leads to an increase of the LaNi5 phase and a decrease of the(La,Mg)Ni3 phase. The as-quenched alloys have a nano-crystalline structure,and the grain sizes of the alloys are in the range of 20-30 nm. The results by the electrochemical measurements indicate that both the discharge capacity and the high rate discharge(HRD) ability of the alloy first increase and then decrease with the variety of quenching rate and obtain the maximum values at the special quenching rate which is changeable with the variety of Mn content. The rapid quenching significantly improves the cycle stabilities of the alloys,but it slightly impairs the activation capabilities of the alloys.
