Graphene-bridged WO3/MoS2 Z-scheme photocatalyst for enhanced photodegradation under visible light irradiation

Abstract In this paper, we aim to design a new photocatalyst with enhanced photocatalytic efficiency by the synergistic construction of a Z-scheme photocatalytic system composed with reduced graphene oxide (rGO)-bridged tungsten trioxide (WO3) and molybdenum disulfide (MoS2). This system shows excellent photocatalytic performances in the degradation of Rhodamine B. WO3/MoS2-rGO nanocomposite with 10% mass fraction of MoS2-rGO exhibits the highest degradation rate of 98.3% under 20 min's visible light irradiation. The degradation rate derived from the apparent first-order kinetics model is calculated as 0.00644 min−1, which is 1.8 and 1.6 times higher than those of pure WO3 and WO3/MoS2. Radical trapping experiment reveals the photo-induced active species hydroxyl and holes are the predominant active species during the reaction. The photocatalytic mechanism of WO3/MoS2-rGO nanocomposite is explained under Z-scheme system theory. Our research may provide new insights into the design and fabrication of high-efficient photocatalyst.