CeVO4 yolk-shell microspheres constructed by nanosheets with enhanced lithium storage performances

Abstract

In this work, the yolk–shell CeVO4 microsphere composed of nanosheets has been prepared via one-spothydrothermal method assisted with citric acid. The coexistence of microsphere, nanosheets subunits, yolk-core and the inner hollow space is helpful in solving the problem of the electrochemical agglomeration and the volume expansion/contraction, also offering easy pathways for the electrolyte to reach every available surface. Benefiting from the unique structure, the sample delivers the high discharge capacity of 661/400 mAh g−1 for the first and 450th cycle at a current density of 0.1 A g−1, respectively, with a corresponding Coulombic efficiency of 64.4/over 99.8%. The contribution from capacitive effects and diffusion-controlled Li+ were analyzed by the voltammetric sweep rate dependence. Such a rarely reported long cycle with higher capacity for CeVO4 has been achieved, which is especially desirable and regarded as a promising candidate anode material for next lithium ion batteries.