In-situ growth of few-layer graphene on ZnO with intimate interfacial contact for enhanced photocatalytic CO2 reduction activity

Intimate interfacial contact between semiconductor photocatalysts and cocatalysts is important for the transfer and separation of photogenerated charge carriers. Herein, few-layer graphene, as an efficient cocatalyst, was in-situ deposited on the surface of ZnO. The composite demonstrated improved photocatalytic CO2 reduction performance than pristine ZnO, ascribing to the intimate interfacial contact and Schottky junction between ZnO and graphene. Meanwhile, photothermal effect of graphene and π-π conjugation interaction between graphene and CO2 molecules also contributed to the performance enhancement. This work not only provides a feasible approach for the in-situ growth of graphene, but also develops an efficient photocatalyst for CO2 reduction.