Introducing proton/electron mediators enhances the catalytic ability of an iron porphyrin complex for photochemical CO 2 reduction.

A novel iron porphyrin complex with hydroquinone moieties as proton/electron mediators at meso positions was designed and synthesised. The complex serves as an efficient catalyst for photochemical CO 2 reduction, and its turnover frequency (TOF = 1.3 × 10 4 h -1 ) was the highest among those of comparable systems with sufficient durability.