Iron porphyrin flanked by viologen redox units for persistent carbon dioxide reduction in the presence of oxygen

A bifunctional catalyst combining iron porphyrin for CO 2 RR and viologen units to selectively divert O 2 reduction was developed. While a dominant ORR over CO 2 RR was observed in homogeneous conditions, the reactivity shifted once heterogenized onto MWCNTs, achieving a 62% FE(CO) under 5% O 2 .