Covalent Organic Frameworks-Based Dyads with Highly Exposed Active Sites and Promoted Mass Transfer for Photocatalytic Hydrogen Evolution.

Covalent organic frameworks (COFs)-based dyads are emerging photocatalysts in solar-driven hydrogen production, it is crucial to expose active sites and promote mass transfer for promoting photocatalytic efficiency. Herein, surfactant-induced dynamic pore-making strategy to construct noble-metal-free photocatalytic systems by combining the ketoenamine-linked COFs on the surface of spinel-structured CuCo₂S₄ (CuCo₂S₄/TpPa-Cl₂) is developed. The open hierarchically porous dyads supply rich active sites and enough channels for mass transfer. Hydrogen evolution rate of CuCo₂S₄/TpPa-Cl₂ is as high as 25.56 mmol g^-1 h^-1 under visible light irradiation, which significantly surpasses those in surfactant-free counterpart (1.63 mmol g^-1 h^-1) and Pt-loaded TpPa-Cl₂ (12.38 mmol g^-1 h^-1). Apparent quantum efficiency at 420 nm reaches 2.24%. This study presents new protocols for constructing noble-metal-free COFs-based photocatalytic systems with efficient solar energy conversion.