Supramolecular photocatalysts constructed with a photosensitizer unit with two tridentate ligands for CO2 reduction

Abstract

New supramolecular photocatalysts comprising an asymmetric bis-tridentate Ru(II) complex that functions as a photosensitizer and a Ru(II) carbonyl complex as the catalyst were designed. The complexes photocatalyzed the reduction of CO₂ to CO or formic acid with high selectivity. The product distribution depended on the catalyst unit. CO and formic acid were the main products when using [Ru(BL)(Clbpy)(CO)]²⁺ (BL = bridging ligand, Clbpy = 4,4′-dichloro-2,2′-bipyridine) and Ru(BL)(CO)₂Cl₂ catalysts, respectively.