Single-source-precursor-assisted synthesis of porous WO3/g-C3N4 with enhanced photocatalytic property

Abstract In this paper, in-situ coupling of WO3 with g-C3N4 (WO3/g-C3N4) was demonstrated by using melamine tungstate as a single-source precursor. The as-prepared WO3/g-C3N4 nanocomposites were structurally characterized by X-ray diffraction (XRD), fourier transform infrared (FTIR) and transmission electron microscopy (TEM). It was found that the single-source precursor not only ensures the close contact between WO3 and g-C3N4, but also endows the porous structure of the product. Thus, the increased visible-light absorption, effective charge separation and enlarged surface area (22.64 m2/g) were achieved for the resultant product. The experimental results showed that WO3/g-C3N4 heterostructure possesses excellent photocatalytic activity for degrading methyl orange (MO) and tetracycline (TC) under the visible light irradiation. Moreover, WO3/g-C3N4 (5 wt%) sample exhibited the best photocatalytic activity. The radicals trap experiments revealed that both •O2− and holes make great contribution to the degradation of pollutants. Accordingly, a Z-scheme charge migration and recombination mechanism was proposed to elucidate the improved photocatalytic properties of WO3/g-C3N4. This study offers a new pathway for optimizing the microstructure of g-C3N4-based function materials and for improving their photocatalytic properties.