Compositional tuning of A_(2)B_(7)-type La_(0.7-x)Y_(x)Mg_(0.3)Ni_(3.5)alloys for gaseous hydrogen storage  

作　　者：Junkun Du Hui Wang Renheng Tang Jiangwen Liu Liuzhang Ouyang Min Zhu 

机构地区：[1]School of Materials Science and Engineering,Guangdong Engineering Technology Research Center of Advanced Energy Storage Materials,South China Universityof Technology,Guangzhou,510640,China

出　　处：《Journal of Rare Earths》2024年第10期1912-1919,共8页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(52271214,51831009)。

摘　　要：Rare earth-based superlattice alloys have great potential for gaseous hydrogen storage,as well as successful application as nickel-metal hydride batteries anodes.In this work,Y substitution was carried out to adjust the gaseous hydrogen storage properties of A_(2)B_(7)-type La_(0.7)Mg_(0.3)Ni_(3.5)alloys.The results indicate a multiphase structure in the alloys comprised of the main rhombohedral Gd_(2)Co_(7)and PuNi_(3)phases,with a small amount of CaCu_(5)phase.Moreover,the Y substitution results in higher abundance of the Gd_(2)Co_(7)phase.The alloy La_(0.42)Y_(0.28)Mg_(0.3)Ni_(3.5)exhibits a hydrogen storage cap acity of 1.55 wt%at 298 K and a desorption plateau pressure of 0.244 MPa.In addition,this alloy demonstrates a stable cycle life by a capacity retention of 94.2%after 50 cycles,with the main capacity degradation occurring during the initial 20 cycles.This work accentuates the potential of the La-Y-Mg-Ni-based superlattice alloys for applications in solid-state hydrogen storage.

关 键 词：Hydrogen storage A_(2)B_(7)-type La-Mg-Ni alloys Y substitution Desorption plateau pressure Cycle performance Rare earths 

分 类 号：TG139.7[一般工业技术—材料科学与工程]