Electrochemical reduction of CO2 in copper particle-suspended methanol

The electrochemical reduction of CO2 in copper particle-suspended methanol was investigated with lead and zinc electrodes. Without copper particles, only formic acid and carbon monoxide were formed in the electrochemical reduction of CO2, and the formation of hydrocarbons could not be observed. On the contrary, hydrocarbons were obtained in the copper particle-suspended electrolyte. The Faradaic efficiencies for methane and ethylene increased gradually with increasing the amounts of copper particles, however the current efficiencies of formic acid and CO decreased. The maximum formation efficiencies of methane were of 6% and 12%, at Pb and Zn electrodes, respectively. It was found to be able to roughly change and control the reduction product distributions by the addition of metal particles into the catholyte in the electrochemical reduction of CO2.