Panchromatic Light-Harvesting Three-Dimensional Metal Covalent Organic Frameworks for Boosting Photocatalysis

Abstract

Constructing artificial photocatalysts with panchromatic solar energy utilization remains an appealing challenge. Herein, two complementary photosensitizers, [Ru(bpy)₃]²⁺ (bpy = 2,2'-bipyridine) and porphyrin dyes, have been cosensitized in metal covalent organic frameworks (MCOFs), resulting in the MCOFs with strong light absorption covering the full visible spectrum. Under panchromatic light irradiation, the cosensitized MCOFs exhibited remarkable photocatalytic H₂ evolution with an optimum rate of up to 33.02 mmol g^-1 h^-1. Even when exposed to deep-red light (λ = 700 ± 10 nm), a commendable H₂ production (0.79 mmol g^-1 h^-1) was still obtained. Theoretical calculation demonstrated that the [Ru(bpy)₃]²⁺ and porphyrin modules in our MCOFs have a synergistic effect to trigger an interesting dual-channel photosensitization pathway for efficient light-harvesting and energy conversion. This work highlights the potential of combining multiple PSs in MCOFs for panchromatic photocatalysis.