Near room temperature and large-area synthesis of ZnO/Cu₂O heterojunction for photocatalytic properties

Large-area ZnO/Cu₂O heterojunction have been successfully synthesized on Cu foil through a simple two-step solution method at near room temperature. The field emission scanning electron microscopy characterization indicates that the morphology of as-prepared Cu₂O film grown on Cu foil is octahedral structure with diameter of ∼450 nm and ZnO is nanorod arrays structure with diameter of ∼150 nm. The current–voltage measurement of ZnO/Cu₂O heterojunction shows a typical rectifying characteristics. Moreover, the photocatalytic test indicates that ZnO/Cu₂O heterojunction exhibits high photocatalytic efficient for degradation of congo red dyes. The possible photocatalytic mechanism of ZnO/Cu₂O heterojunction is also presented.