Enhanced photocatalytic activity of Cu-doped ZnO nanorods

► Cu-doped ZnO nanorods with different Cu concentrations were synthesized through vapor transport method.► The photocatalytic activity of these synthesized Cu-doped nanorods was studied by the photodegradation of resazurin dye.► Cu-doped ZnO nanorods effectively decomposed the resazurin in a short time compared to undoped ZnO.► The increased photocatalytic activity of Cu-doped ZnO is due to large intrinsic oxygen vacancies and extrinsic defects.