Synthesis of CeO2 nanocrystals with controlled size and shape and their influence on electrochemical performance

Abstract In this work, nanosphere-like and nanowire shaped CeO 2 nanocrystals were prepared at room temperature utilizing the epoxide precipitation reaction in aqueous and ethanolic solutions. It was found that the shape of CeO 2 nanocrystals depends on the reaction kinetics of epoxide in solution. The isotropic growth of nanocrystals in aqueous solution resulted in the formation of CeO 2 nanocrystals with sphere-like shape, while the anisotropic growth of nanocrystals in ethanolic solution led to the nanowire shape of CeO 2 nanocrystals. The anisotropic growth of nanocrystals was attributed to the high surface energy of their {110} facet induced from the active reaction of epoxide in ethanolic solution. The reaction kinetics of epoxide affected not only the size and crystallinity of CeO 2 nanocrystals, but also their shape. As a result, the produced CeO 2 nanocrystals had different electrochemical performance. As an electrode material for application in supercapacitor, the nanosphere-like CeO 2 nanocrystals presented better electrochemical performance and longer cycle life than the packed CeO 2 nanowires. Graphical Abstract Nanosphere-like and nanowire shaped CeO2 nanocrystals were prepared utilizing the epoxide precipitation reaction in aqueous and ethanolic solutions. It was found that the shape of CeO2 nanocrystals depends on the reaction kinetics of epoxide in solution. The isotropic growth of nanocrystals in aqueous solution produced CeO2 nanocrystals with sphere-like shape, while the anisotropic growth of nanocrystals in ethanolic solution produced nanowire shaped CeO 2 . As an electrode material for application in supercapacitor, the nanosphere-like CeO 2 nanocrystals presented better electrochemical performance and longer cycle life than the packed CeO 2 nanowires.