In situ construction of WO3/g-C3N4 composite photocatalyst with 2D–2D heterostructure for enhanced visible light photocatalytic performance

A WO3/g-C3N4 composite photocatalyst with 2D–2D heterostructure was designed and constructed to boost the visible light performance for degradation of organic pollutants by an in situ preparation strategy. The degradation of RhB as a model reaction was used to evaluate the photocatalytic activity of the WO3/g-C3N4 photocatalyst. The optimized mass fraction of WO3 is 13% for the WO3/g-C3N4 composite photocatalyst, namely the CNW-13 sample, which can almost completely degrade the pollutant in 40 min under 70 W metal halide lamp irradiation. The different contents of WO3/g-C3N4 composite photocatalysts were investigated in detail by a series of detailed characterization measurements. Based on the trapped active species and photoelectrochemical experiments, the enhanced photocatalytic performance of WO3/g-C3N4 can be ascribed to the formation of a Z-scheme system to accelerate the separation and transfer of photo-generated charge carriers. Furthermore, the major active species, superoxide radical (·O2−), also can be determined by active species-trapping experiments. It is expected that our current work could provide a counterpart to further develop the efficient composite photocatalysts in practical applications.