Hierarchical Sr-ZnO/g-C3N4 heterojunction with enhanced photocatalytic activities

It is urgent to develop new photocatalytic materials that could optimize H-2 generation and efficiently degrade environmentally persistent pollutants. Herein, Sr-ZnO/g-C3N4 spherical flowers composed of hierarchical nanorods composites have been successfully synthesized via facile single step method and utilized in photocatalysis for efficient degradation of Methylene green (MG) and H-2 production under UV-vis irradiation. The resultant SrZnO/g-C3N4 showed enhanced activities for MG degradation (i.e. 96 % in 20 min), and H-2 evolution (31.2 mu molh(-1) g(-1)) which is much obvious compared to the bare g-C3N4, ZnO and Sr-ZnO. It is investigated that Sr ion doping has extended the light absorption toward visible light region. The g-C3N4 grafted Sr-ZnO provided an extra boost up absorption spectra in the visible light region compared to bare ZnO. The photoluminescence spectroscopy and photo-electrochemical measurement confirmed excellent photo-generated charge carrier's separation in the hierarchical structure of spherical flowers. The improved activities are attributed to the combined impact of in-situ doping, hierarchical morphology, and heterojunction formation.