An Iron Quaterpyridine Complex as Precursor for the Electrocatalytic Reduction of CO₂ to Methane

A Fe quaterpyridine complex was used as a molecular precursor for the electrochemical reduction of CO₂ to CH₄ in acetonitrile in the presence of triethanolamine. CH₄ was produced with a faradaic yield of approximately 2.1 % at 25 °C and 1 atm pressure of CO₂ as reactant. Controlled potential electrolysis coupled to ex situ X-ray photoelectron spectroscopy and X-ray absorption spectroscopy of the electrode surface revealed the formation of metallic iron covered by iron oxides as species responsible for catalysis.