Improved hydrogen production performance of an S-scheme Nb₂O₅/La₂O₃ photocatalyst

Addressing the intricate challenge of simultaneously improving the separation of photoinduced electron-hole pairs and enhancing redox potentials to produce hydrogen fuel demands the rational design of S-scheme heterojunction photocatalysts. Herein, we used a hydrothermal process to integrate Nb₂O₅ nanorods and La₂O₃ nanosheets to design an Nb₂O₅/La₂O₃ S-scheme system for photocatalytic hydrogen production under simulated sunlight illumination. Notably, the optimal hydrogen production performance of Nb₂O₅/La₂O₃ (the molar ratio of Nb₂O₅ to La₂O₃ is 0.4% and denoted as 0.4NbO-LaO) reached 2175 μmol h^-1 g^-1, which is 14.5 and 15.9 times superior in comparison with those of pure Nb₂O₅ and La₂O₃, respectively. In addition, repeated experiments verify the strong stability of the 0.4NbO-LaO photocatalyst. The S-scheme mechanism, verified by the in situ XPS method, plays a crucial role in producing hydrogen with a significantly higher yield than pure Nb₂O₅ and La₂O₃. This design approach offers an innovative avenue to widen the scope of S-scheme photocatalysts for solar fuel production.