2D/2D WO₃·H₂O/g-C₃N₄ heterostructured assemblies for enhanced photocatalytic water decontamination via strong interfacial contact

A strong interfacial contact of heterostructured photocatalysts plays a key role in charges migration, thus promoting photocatalytic performance. Benefiting from the unique two-dimensional (2D) morphology and abundant terminals, 2D/2D "face-to-face" WO₃·H₂O/g-C₃N₄ heterostructured self-assemblies were fabricated employing tungsten oxide hydrate (WO₃·H₂O) nanoplates and graphitic carbon nitride (g-C₃N₄) sheets as precursors. Compared to pristine WO₃·H₂O and g-C₃N₄, the binary WO₃·H₂O/g-C₃N₄ heterostructures exhibit excellent photocatalytic performance towards water decontamination, using organic dye rhodamine B/methyl orange as probes. It is found that WO₃·H₂O/g-C₃N₄ with 20 wt% mass ratio (WHC-20) possesses the best photocatalytic activities, with about 3.05 times higher than that of pristine g-C₃N₄. The remarkable increase performance is attributed to the enhanced evolution of superoxide radicals (·O₂⁻) via photoreduction in adsorbed oxygen molecules (O₂⁻), which are promoted by efficient Z-scheme charges separation and rapid electrons transfer at 2D/2D interface. Given the low-cost, facile synthetic procedure and recycling stability, the heterostructured WO₃·H₂O/g-C₃N₄ could be served as a promising photocatalyst to deal with water contamination.