▎ 摘　　要

Fabrication of an interconnected and conductive nano-architecture has been a prospective strategy to design a high-performance and low cost electrocatalyst for oxygen reduction reaction (ORR). Herein, a novel nano-architecture assembled by graphene nanosheets and CeO2 nanowires (NWs) with a hierarchical structure has been developed by a facile hydrothermal process using ethanol/water as solvents without any organic additives. In this framework, graphene oxide (GO) has been reduced to graphene and chemical bonding formed between the GO and CeO2 (NWs) in a hydrothermal process. The imbedded CeO2 (NWs) has been prevent the restacking of the graphene sheets and improved the electrical conductivity of the hybrid catalyst. The effect of different ratios of GO to CeO2 (Nws) in the hybrid have been studied. The rGO(3)-CeO2 (NWs) composite exhibited better catalytic performance with slow attenuation and high limiting current density 3.55 and 1.99 times higher than CeO2 (NWs) and pure GO. The onset potential of rGO(3)-CeO2 (NWs) is 0.13 V and 0.05 V positive shift from that of CeO2 (NWs) and pure GO, respectively, suggesting that the rGO(3)-CeO2 (NWs) hybrid has been an excellent stability and activity for ORR. It has been found that CeO2 (NWs) served not only as an effective catalyst but also as an "oxygen buffer" to relieve oxygen insufficiency for ORR.