Development of efficient photocatalytic systems for CO2 reduction using mononuclear and multinuclear metal complexes based on mechanistic studies

Photocatalytic systems for CO2 reduction using metal complexes, especially rhenium(I) complexes as a main component, are reviewed: mononuclear Re(I) complexes, mixed systems with two different Re(I) complexes, and supramolecule systems with a Re(I) complex connected to a ruthenium(II) complex. We focus on the mechanistic studies and the architecture for constructing the photocatalytic systems based on the mechanism.