2D/2D mesoporous BiVO4/crystalline carbon nitride S-scheme photocatalysts for hydrogen production and simultaneous MO degradation

Photocatalytic H2 production from wastewater offers a promising strategy for simultaneous water purification and renewable energy production. However, this approach faces significant challenges including rapid recombination of photogenerated charge carriers and limited oxidizing capacity of the photocatalysts. Herein, a 2D/2D mesoporous BiVO4/CCN S-scheme heterojunction photocatalyst is constructed via in situ hydrothermal growth bismuth vanadate (BiVO4) on crystalline carbon nitride (CCN). The successful formation of the S-scheme heterojunction between BiVO4 and CCN is confirmed by X-ray photoelectron spectroscopy (XPS), radical trapping experiments, and electron paramagnetic resonance (EPR) analysis. The optimized 2D/2D BiVO4/CCN heterojunction effectively suppresses charge recombination while maintaining outstanding redox capability, leading to a remarkable H2 evolution rate of 14.7 mmol h−1 g−1 - 49 times higher than that of pristine CCN (0.3 mmol h−1 g−1) when using methyl orange (MO) as the sacrificial agent. This work provides a feasible strategy for designing efficient bifunctional photocatalysts that enable simultaneous wastewater treatment and renewable hydrogen production.