Hot-electron-assisted S-scheme heterojunction of tungsten oxide/graphitic carbon nitride for broad-spectrum photocatalytic H2 generation

Extended light absorption and dynamic charge separation are vital factors that determine the effectiveness of photocatalysts. In this study, a nonmetallic plasmonic S-scheme photocatalyst was fabricated by loading 1D plasmonic W 18 O 49 nanowires onto 2D g-C 3 N 4 nanosheets . W 18 O 49 nanowires play the dual role of a light absorption antenna—that extends light adsorption—and a hot electron donor—that assists the water reduction reaction in a wider light spectrum range. Moreover, S-scheme charge transfer resulting from the matching bandgaps of W 18 O 49 and g-C 3 N 4 can lead to strong redox capability and high migration speed of the photoinduced charges. Consequently, in this study, W 18 O 49 /g-C 3 N 4 hybrids exhibited higher photocatalytic H 2 generation than that of pristine g-C 3 N 4 under light irradiation of 420–550 nm. Furthermore, the H 2 production rate of the best-performing W 18 O 49 /g-C 3 N 4 hybrid was 41.5 μmol·g −1 ·h −1 upon exposure to monochromatic light at 550 nm, whereas pure g-C 3 N 4 showed negligible activity. This study promotes novel and environmentally friendly hot-electron-assisted S-scheme photocatalysts for the broad-spectrum utilization of solar light.