Rhenium-functionalized covalent organic framework photocatalyst for efficient CO2 reduction under visible light

Abstract

The conversion of carbon dioxide (CO 2 ) into value-added chemicals under photochemical conditions has attracted increasing attention in recent years. One of the great challenges is to develop novel active catalysts under visible light irradiation with sustained lifetime and high activity. In this regard, herein, we report a highly efficient, stable and recyclable photocatalyst by embedding photoactive rhenium complex (Re(CO) 5 Cl) into porous, crystalline, bipyridine-based covalent organic frameworks (COFs). The rhenium post-metallated COFs exhibits salient photocatalytic activity towards CO 2 reduction into CO under visible light. The quantity of the CO produced on Re-functionalized COFs is twice higher than that produced on the famous Re(bpy)(CO) 3 Cl (bpy = 2,2′-bipyridine) molecular photocatalyst under similar reaction conditions. • Covalent organic framework with monodispersed metallic catalytic site was synthesized. • It served as photocatalyst for CO 2 reduction with sustained lifetime up to 12 h. • Molecular catalysis was realized in heterogeneous catalysis with a higher efficiency. • Mechanism of photocatalytic performance was explored by a new in-situ FTIR reactor.