Ionic liquid assisting synthesis of ZnO/graphene heterostructure photocatalysts with tunable photoresponse properties

A simple and efficient strategy for synthesis of ZnO/graphene heterostructure photocatalysts was demonstrated using an ionic liquid assisting solvothermal method. The polyvinylpyrrolidone (PVP) functionalized graphene oxide (GO) as starting material could be easily reduced under an ethanol solvothermal condition, with the concomitant growth of ZnO nanoparticles of quantum dot size on the graphene surface. Quantum dot sized ZnO nanoparticles deposited on graphene sheets with a p/n heterojunction interface were demonstrated by a change of photocurrent direction at different bias potential that significantly enhanced photoresponse properties under solar light irradiation. [Display omitted] ► The ZnO/graphene with a p/n heterojunction was obtained using an ionic liquid method. ► The ZnO/graphene can be completely responded in visible region. ► The ZnO/graphene can serve as advanced materials of photon-to-current. ► The ZnO/graphene has great potential applications for photo diode in the further.