Abstract
Molecular catalysts that combine high product selectivity and high current density for CO2 electrochemical reduction are urgently needed. Here, we report that a cobalt phthalocyanine bearing a trimethyl ammonium group appended to the phthalocyanine macrocycle reduces CO2 to CO in water with high activity over a broad pH range. In a flow cell operating under basic conditions, this molecular catalyst achieved excellent CO selectivity, good stability, and a maximum CO partial current density of 165 mA cm–2, matching the performance of highly active noble-metal nanocatalysts.