One-step calcination preparation of worm-like ZnO@BiOI heterojunction with enhanced visible light response for mild photooxidation reaction

Abstract

ZnO@BiOI nanocomposite has been prepared by a one-step calcination method and characterized by XRD, SEM and HRTEM. The photocatalytic activity of ZnO@BiOI nanocomposite was examined by the photooxidation of 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (1,4-DHP) under visible light irradiation (λ > 400 nm). Compared with pure ZnO and BiOI, the photocatalytic activity of ZnO@BiOI was dramatically enhanced. In addition, the 1,4-DHP was quantitatively converted to its pyridine derivatives by the mild oxidation without deep oxidation or degradation. Mechanism study showed that superoxide anionic radicals (·O2−) and photogenerated holes (h+) were the major active species.