Photoreduction of CO2 in the [Ru(bpy)2(CO)2]2+/[Ru(bpy)3]2+ or [Ru(phen)3]2+/Triethanolamine/N,N-Dimethylformamide System

The [Ru(bpy)2(CO)2]2+/[Ru(bpy)3]2+ (or [Ru(phen)3]2+)/triethanolamine/N,N-dimethylformamide system reduces CO2 to afford HCOO− efficiently under the irradiation of light (λ>320 nm), where each of the former three components functions as a catalyst, a photosensitizer, and an electron donor, respectively.