Robust S-scheme ZnO-TiO2-Ag with efficient charge separations for highly active hydrogen evolution performance and photocatalytic mechanism insight

The design and fabrication of photocatalysts for robust H2 evolution from photocatalytic water splitting has emerged as a hotspot in the domain of photocatalysis. Therefore, we have designed an S-scheme ZnO-TiO2-Ag (Zn-Ti-Ag) catalyst through the hydrothermal process to investigate photocatalytic H2 production under simulated sunlight exposure. The H2 production efficiency of Zn-Ti-Ag catalyst from water/formic acid solution is 60.4 mmolh−1g−1, which is exceptionally greater than that of pure ZnO (0.39 mmolh−1g−1) under identical experimental conditions. After five successive cycles, no obvious decline of photocatalytic activity over Zn-Ti-Ag verifies its outstanding stability for large-scale application. The exceptionally enhanced photocatalytic performance of Zn-Ti-Ag heterojunction can be attributed to efficient photocarriers separation and transport efficiency, improved light absorption resulting from the LSPR effect of Ag, and powerful redox potentials due to the construction of S-scheme. This research provides an efficient orientation to understand and design LSPR phenomenon-assisted oxides-based S-scheme heterojunctions for diverse photocatalytic applications