Controlled Synthesis of CeO₂/Graphene Nanocomposites with Highly Enhanced Optical and Catalytic Properties

Abstract

In this paper, CeO 2 nanocubes with the (200)-terminated surface/graphene sheet composites have been prepared successfully by a simple hydrothermal method. It is found that the CeO 2 nanocubes with high crystallinity and specific exposed surface are well dispersed on well-exfoliated graphene surface. The (200)-terminated surface/graphene sheet composites modified electrode showed much higher sensitivity and excellent selectivity in its catalytic performance compared to a CeO 2 nanoparticle-modified electrode. The photoluminescence intensity of the CeO 2 anchored on graphene is about 30 times higher than that of pristine CeO 2 crystals in air. The higher oxygen vacancy concentration in CeO 2 is supposed to be an important cause for the higher photoluminescence and better electrochemical catalytic performance observed in the (200)-terminated surface/graphene sheet composites. Such ingenious design of supported well-dispersed catalysts in nanostructured ceria catalysts, synthesized in one step with an exposed high-activity surface, is important for technical applications and theoretical investigations.