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 (WO) materials possess rich composition/morphology and an extended light response in the near-infrared region, WO is a quite popular nanocomponent for modifying g-C₃N₄, forming heterostructures that can be used for various photocatalytic applications involving water splitting, CO₂ reduction, NO removal, H₂O₂ generation, and related chemical to fuel conversion reactions. In this review, important aspects of WO/g-C₃N₄ heterostructure photocatalysts are reviewed to provide paradigms for composition adjustment, structural design, and photocatalytic applications of these materials. The WO 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 WO/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.