Integration of [(Co(bpy)₃]²⁺ electron mediator with heterogeneous photocatalysts for CO₂ conversion.

An efficient chemical system for electron generation and transfer is constructed by the integration of an electron mediator ([Co(bpy)3](2+); bpy=2,2'-bipyridine) with semiconductor photocatalysts. The introduction of [Co(bpy)3](2+) remarkably enhances the photocatalytic activity of pristine semiconductor photocatalysts for heterogeneous CO2 conversion; this is attributable to the acceleration of charge separation. Of particular interest is that the excellent photocatalytic activity of heterogeneous catalysts can be developed as a universal photocatalytic CO2 reduction system. The present findings clearly demonstrate that the integration of an electron mediator with semiconductors is a feasible process for the design and development of efficient photochemical systems for CO2 conversion.