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Improved Mass-Transfer Enhances Photo-Driven Dye Degradation and H₂ Evolution over a Few-Layer WS₂/ZnO Heterostructure.

ABSTRACT: In this study, we observed the enhanced photocatalytic activity of a few-layer WS₂/ZnO (WZ) heterostructure toward dye degradation and H₂ production. The few-layer WS₂ acted as a co-catalyst that separated photogenerated electron/hole pairs and provided active sites for reactions, leading to the rate of photocatalytic H₂ production of WZ being 35% greater than that over the bare ZnO nanoparticles. Moreover, vortex-stirring accelerated the mass-transfer of the reactants, leading to the efficiency of dye photodegradation being 3 times higher than that obtained without high-speed stirring. We observed a similar effect for H₂ production, with greater photocatalytic performance arising from the increased mass-transfer of H₂ from the catalyst surface to the atmosphere.

SUBMITTER: Huang YJ

PROVIDER: S-EPMC8771954 | biostudies-literature |

REPOSITORIES: biostudies-literature

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