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

In this work, nanosphere-like and nanowire shaped CeO₂ nanocrystals were prepared at room temperature 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 resulted in the formation of CeO₂ nanocrystals with sphere-like shape, while the anisotropic growth of nanocrystals in ethanolic solution led to the nanowire shape of CeO₂ 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 CeO₂ nanocrystals, but also their shape. As a result, the produced CeO₂ nanocrystals had different electrochemical performance. As an electrode material for application in supercapacitor, the nanosphere-like CeO₂ nanocrystals presented better electrochemical performance and longer cycle life than the packed CeO₂ nanowires.

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 CeO₂. As an electrode material for application in supercapacitor, the nanosphere-like CeO₂ nanocrystals presented better electrochemical performance and longer cycle life than the packed CeO₂ nanowires.