Reduction of CO2 to CO at Low Overpotential in Neutral Aqueous Solution by a Ni(cyclam) Complex Attached to Poly(allylamine)

Abstract

Less is more: Nickel cyclam complexes are known as efficient catalysts for the electrochemical reduction of CO(2) to CO, despite having overvoltages of more than 0.6 V. Incorporating [Ni(cyclam)](2+) into poly(allylamine) through axial coordination of pyridine enables the electrochemical reduction of CO(2) to CO near the thermodynamic potential of -0.78 V (vs. Ag/AgCl) at pH 8 with a current efficiency of 90 %.