▎ 摘　　要

Light-induced water splitting by artificial photocatalysis is one of the cornerstones to produce sustainable energy. Plasmonic photocatalyst exhibits considerable photoactivities under a wide range of the solar spectrum and therefore designing sophisticated plasmonic photocatalyst is important to realize high efficient solar conversion. Here, we fabricate CuCo/reduced graphene oxide junctions tailored for photocatalytic water splitting without a sacrificial agent. The CuCo bimetal converts the energy of sunlight into surface plasmon resonance oscillations and transfer the plasmonic energy to electron-hole pair via Landau damping. Electron in the CuCo bimetal will spontaneously transfer to reduced graphene oxide, which greatly improve the separation efficiency of electronhole pair as compared to the CuCo bimetal alone. Compared to the pure Cu, the CuCo bimetal unveils an expected enhancement of photocatalytic activity due to the synergistic interaction in the bimetallic material. Taken together, our studies offer experimental validation of water splitting of plasmonic photocatalyst and demonstrate an improvement of photocatalytic activity of pure Cu after alloying with Co and modification with reduced graphene oxide.