Investigation of charge transfer in Au nanoparticle-ZnO nanosheet composite photocatalysts.

Ohmic contact formation at the interface of the Au nanoparticle (NP)-ZnO nanosheet (NS), which facilitates photoelectron transfer from ZnO NSs to Au NPs, is determined by scanning Kelvin microscopy for the first time. Reduction of charge recombination in the ZnO NSs confirmed by the quench of green band emission results in the enhancement of photocatalytic activity of the Au NP-ZnO NS composite.