Boosting interfacial S-scheme charge transfer and photocatalytic H2-production activity of 1D/2D WO3/g-C3N4 heterojunction by molecular benzene-rings integration

A novel benzene-ring engineered 1D/2D WO3/g-C3N4 S-scheme photocatalyst (BCNW) was rationally designed and successfully synthesized by the electrostatic self-assembly method. Experimental and Density Functional Theory results reveal that the integration of molecular benzene-ring in the framework of g-C3N4 can not only narrow its bandgap and accelerate charge separation by forming a mid-state at the top of its valence band but more importantly open up a new additional bridge for speeding up the interfacial S-scheme charge transfer in BCNW. Benefitting from those multiple positive effects of benzene-ring integration, as expected, BCNW S-scheme photocatalysts show superior photocatalytic H2-production activity and reach 2971 μmol h–1 g–1 under visible-light illumination, which is 3.35 times WO3/g-C3N4 S-scheme photocatalyst without benzene-ring integration. This work supplies an innovative strategy for the design of a high-efficiency S-scheme photocatalytic system by constructing a facile and additional molecular charge transfer channel at the interface.