Preparation of p–n junction Cu2O/BiVO4 heterogeneous nanostructures with enhanced visible-light photocatalytic activity

p–n junction Cu2O/BiVO4 heterogeneous nanostructures for enhancement of visible-light photocatalytic properties of BiVO4 nanocrystals have been successfully prepared through coupling a hydrothermal process with polyol strategy. The assembly of p-type Cu2O nanoparticles produces a large number of nano p–n junction heterostructures on the surface of the BiVO4 nanocrystals, where Cu2O and BiVO4 form p- and n-type semiconductors, respectively. The experimental results reveal that these p–n junction Cu2O/BiVO4 heterogeneous nanostructures exhibit much higher visible-light photocatalytic activities than the individual BiVO4 nanocrystals for the degradation of model dyes methylene blue and colorless organic phenol under visible light irradiation. The enhanced photocatalytic efficiencies are attributed to the charge transfer from n-type BiVO4 to the attached p-type Cu2O nanoparticles, which effectively reduces the recombination of electrons and holes, leading to the enhancement of the photocatalytic properties of the heterostructure nanostructures. These new p–n junction heteronanostructures are expected to show considerable potential applications in solar-driven wastewater treatment.