Regenerative Methanol Fuel Cells: Reduction of CO2 to Methanol on Oxidized Cu Electrodes

Electrocatalytic conversion of CO2 to fuels may enable a practical and efficient method to store energy from renewable sources. In previous studies, either carbon monoxide or formic acid were found as products of CO2 reduction in aqueous solutions at most metal electrodes. Copper electrocatalysts were unique among pure metals since hydrocarbons such as methane and ethylene were produced at up to 80 % Coulombic efficiencies. While methane may be used as a fuel, liquid-phase fuels such as methanol are particularly attractive as reduction products since they are easily stored and may be used in direct methanol fuel cells (DMFCs) or conventional internal combustion engines. Regenerative CO2/MeOH systems also hold th