Electrochemical reduction of carbon dioxide with an electrode mediator and homogeneous catalysts

Article abstract of DOI:10.1016/0304-5102(89)80191-9

Carbon dioxide has been reduced catalytically to methanol with an electrode mediator and homogeneous catalysts, using a hydrogen fuel cell as an energy source to regenerate the active mediator. Thermodynamic assessment predicts that the reversible potential for the reaction H⁺ + e^- = 1/2 H₂ should be more negative than that for the reaction CO₂ + 6H⁺ + 6e^- = CH₃OH + H₂O whenever a fuel cell with hydrogen as the fuel and CO₂ as the oxidant is feasible. As reaction proceeded, the pH of the catholyte rose but that of the anolyte dropped, until finally reduction of CO₂ ceased. Hence, adjustment of the pH values in both temperatures was necessary to maintain CO₂ reduction over long time periods.