Tungsten Oxide/g-C3N4 Heterostructures: Composition, Structure, and Photocatalytic Applications

The construction of heterostructures promotes extending the light adsorption range of graphitic carbon nitride (g-C3N4) materials, improving the photogenerated charge carrier separation/transfer efficiency for attaining much enhanced performances. Because defective tungsten oxide (WOx) materials possess rich composition/morphology and an extended light response in the near-infrared region, WOx is a quite popular nanocomponent for modifying g-C3N4, forming heterostructures that can be used for various photocatalytic applications involving water splitting, CO2 reduction, NOx removal, H2O2 generation, and related chemical to fuel conversion reactions. In this review, important aspects of WOx/g-C3N4 heterostructure photocatalysts are reviewed to provide paradigms for composition adjustment, structural design, and photocatalytic applications of these materials. The WOx growth control in amorphous and crystalline g-C3N4, adjustment on heterostructure types (e.g., type II and Z-scheme), and the catalytic performances of the composite system are also discussed in detail. Moreover, the effects of synthetic methodologies and preparation parameters on the formation of two-dimensional layered heterostructures are discussed to provide inspiration for the construction of state-of-the-art WOx/g-C3N4 heterostructures that can be utilized for photoredox reactions. The challenges and prospects of the heterostructure formation and the photocatalytic applications of the heterostructures in future research are also summarized.