Facile preparation of ZnO:g-C3N4 heterostructures and their application in amiloride photodegradation and CO2 photoreduction

Semiconductor heterojunctions are interesting strategies for the development of efficient photocatalysts. In this paper we report the synthesis of ZnO:g-C3N4 heterostructures with different percentages of g-C3N4 (15%, 50% and 85%) using an easy and new method: precipitation of ZnO by alkaline solution at room temperature on g-C3N4 surface. The nucleation of ZnO nanoparticles had effective interaction on the g-C3N4 surface, showing good crystallinity and uniformity, which improved the heterostructure stability and the separation of photogenerated charge carriers, consequently increasing the photocatalytic efficiency for both the degradation of the amiloride (AML) drug and the conversion of CO2 into products such as CO, CH4 and C2H4. •Synthesis of highly crystalline ZnO at room temperature.•A new and facile method for the preparation of ZnO:g-C3N4 heterostructures.•Photochemical stabilization of ZnO by association with g-C3N4.•Photodegradation of amiloride under visible light.•Photocatalytic reduction of CO2 into value-added products.