Electrochemical Reduction of Carbon Dioxide and Iron Oxide in Molten Salts to Fe/Fe3 C Modified Carbon for Electrocatalytic Oxygen Evolution.

Non-noble electrocatalyst for the oxygen evolution reaction (OER) is essential for water electrolysis and electrochemical conversion of CO2 . Integrating electrochemical fixation of CO2 and electrochemical metallurgy to prepare advanced OER electrocatalyst is a promising solution to promote carbon neutrality and renewable energy. Herein, the electrochemical reduction of CO2 and Fe2 O3 are combined in molten salts to prepare cathodic Fe3 C-based electrocatalyst and anodic oxygen at 600 °C with enhanced current efficiency. The resulting Fe3 C-based electrocatalyst outperforms precious electrocatalyst towards the OER operation in 1 M KOH due to a dynamic structural evolution to form an interface of Fe3 C-FeOOH.