Photogenerated electron reservoir in hetero-p–n CuO–ZnO nanocomposite device for visible-light-driven photocatalytic reduction of aqueous Cr(vi)

Abstract
A 3D CuO–ZnO p–n junction hierarchical device was fabricated via sequential in situ crystallization and hydrothermal reaction on Cu foil and exhibited enhanced visible light photocatalytic reduction with stable recyclability to Cr(vi).