Effect of CeO2-based solid solutions on hydrogen storage kinetic properties of Mg2Ni alloy

Abstract

Nanosized Ce1-x(Eu0.5La0.5)xO2 and Ce1-x(Fe0.5La0.5)xO2 solid solutions were synthesized via hydrothermal method, and the doping effect was characterized by analyzing the structure and spectrum features of the solid solutions. The results showed that the cell parameters of the solid solutions increased, the absorption edge of the UV diffuse reflectance spectroscopy was drifted, and the characteristic Raman F2g vibration peak shifted to lower wave numbers. Then the mixtures of Mg2Ni alloy powders and the solid solution additives were ball-milled to obtain composites. XRD results showed that the fraction of amorphous and nanocrystalline in the as-prepared composites was increased. The hydrogen storage kinetic measurements demonstrated that surface activity and degree of reversibility of the composites was optimized, and the diffusion rate and diffusion coefficient of hydrogen atoms in the bulk of Mg2Ni were increased.