Construction of direct Z-scheme g-C3N4/BiYWO6 heterojunction photocatalyst with enhanced visible light activity towards the degradation of methylene blue.

Abstract

Construction of the Z-scheme heterojunction photocatalyst achieved highly improved photocatalytic ability by its high redox ability of the photoinduced e--h+ pairs. In the study, Z-scheme g-C3N4/BiYWO6 heterojunction photocatalyst is prepared by the single-step hydrothermal method. Further, its photocatalytic ability was assessed by degrading methylene blue under visible light exposure. Particularly, the optimized 30 wt% of g-C3N4 in the g-C3N4/BiYWO6 composite exposes almost complete degradation after 90min, that is ~ 3.0 times greater than the bare BiYWO6 and g-C3N4 with the rate constant value 0.032min-1. Experimentally, the radical trapping studies indicate O2·- and ·OH radicals are playing a vital role in the photocatalytic degradation process. Also, the Z-scheme g-C3N4/BiYWO6 heterojunction photocatalyst exhibits excellent photoelectrochemical property and it is stable after 5 cycles, which indicates its good reusability nature. These enhancements are due to the newly formed heterostructure that facilitates the migration and separation efficiency of the photoproduced e--h+ pairs. Hence, the synthesized Z-scheme g-C3N4/BiYWO6 heterostructure could be an excellent material for wastewater remediation works.