Sea-urchin-like ReS₂ nanosheets with charge edge-collection effect as a novel cocatalyst for high-efficiency photocatalytic H₂ evolution

The recombination of charge carriers arriving from the random charge movement in semiconductor photocatalysts greatly limits the practical application of solar-driven H₂ evolution. The design of photocatalytic systems with spatially oriented charge-transfer is a promising route to achieve high charge-separation efficiency for photocatalysts. Herein, novel sea-urchin-like ReS₂ nanosheet/TiO₂ nanoparticle heterojunctions (SURTHs) are constructed. The unique sea-urchin-like structure endows the ReS₂ cocatalyst with an unusual charge edge-collection effect, which leads to a significant acceleration of charge separation and transfer, as evidenced by the well-designed selective photodeposition of Pt quantum dots in SURTHs. The markedly improved charge transfer capacity contributes to a high photocatalytic H₂ evolution rate of 3.71 mmol h⁻¹ g⁻¹ for SURTHs (an apparent quantum efficiency (AQE) of 16.09%), up to 231.9 times by contrast with that of P25 TiO₂. This work would provide a new platform for designing the high-efficiency cocatalyst/photocatalyst system with excellent charge transfer capacity.