Paired Electrosynthesis of Formaldehyde Derivatives from CO2 Reduction and Methanol Oxidation

Abstract Utilizing CO2‐derived formaldehyde derivatives for fuel additive or polymer synthesis is a promising approach to reduce net carbon dioxide emissions. Existing methodologies involve converting CO2 to methanol by thermal hydrogenation, followed by electrochemical or thermochemical oxidation to produce formaldehyde. Adding to the conventional methanol oxidation pathway, we propose a new electrochemical approach to simultaneously generate formaldehyde derivatives at both electrodes by partial methanol oxidation and the direct reduction of CO2. To achieve this, a method to directly reduce CO2 to formaldehyde at the cathode is required. Still, it has been scarcely reported previously due to the acidity of the formic acid intermediate and the facile over‐reduction of formaldehyde to methanol. By enabling the activation and subsequent stabilization of formic acid and formaldehyde respec…