Gas phase reduction of carbon monoxide to formaldehyde and ethylene was found in electrochemical cell with an inorganic ion exchanger α-Zr(HPO4)2·H2O used as solid proton-conducting electrolyte at room temperature and atmospheric pressure. The type and amount of the electroreduction of CO depend on the different metal electrodes and current densities, which gives a link between heterogeneous catalysis and electrochemistry. Gas phase reduction of carbon monoxide to formaldehyde and ethylene was found in electrochemical cell with an inorganic ion exchanger α-Zr (HPO4) 2 · H2O used as solid proton-conducting electrolyte at room temperature and atmospheric pressure. The type and amount of the electroreduction of CO depend on the different metal electrodes and current densities, which gives a link between heterogeneous catalysis and electrochemistry.