Construction of a WO3/Cu2WS4 heterojunction for enhanced visible-light photocatalytic degradation of styrene

WO 3 /Cu 2 WS 4 heterojunction photocatalyst is fabricated by a solvothermal route. • WO 3 /Cu 2 WS 4 displays strong visible-light photocatalytic activity for gaseous styrene degradation. • Optimized composite delivers better degradation efficiency and reaction kinetics than pure components. • Z-scheme charge transfer mechanism is put forward to interpret the elevated photocatalytic activity. In this work, a Z -scheme heterojunction photocatalyst WO 3 /Cu 2 WS 4 was prepared by loading Cu 2 WS 4 particles on the surface of bulk WO 3 . Under simulated visible light irradiation, the catalyst exhibited excellent photocatalytic oxidation performance toward styrene (200 mg/m 3 ). The optimal WO 3 /CWS-20% composite achieved the highest photocatalytic oxidation efficiency for styrene, with a degradation rate of 97.2% and a corresponding rate constant of 0.03651 min −1 , which was 2.8 and 3.2 times higher than those of pure WO 3 and Cu 2 WS 4 , respectively. Moreover, the material possessed good stability, maintaining 83.4% of its degradation efficiency after four consecutive cycles. The electron transfer and catalytic mechanisms of the catalyst were further investigated via photoelectrochemical measurements. The results indicate that the constructed Z -scheme heterojunction can effectively separate photogenerated charge carriers and facilitate the generation of reactive species such as hydroxyl radicals (·OH) and superoxide anion radicals (·O 2 − ). This work offers a novel strategy for designing high-efficiency heterojunction photocatalysts for the degradation of VOCs under sunlight irradiation. Download: Download high-res image (80KB) Download: Download full-size image