Electrochemical reduction of CO2 to ethanol using copper nanofoam electrode and 1-butyl-3-methyl-imidazolium bromide as the homogeneous co-catalyst

In this research, an electrochemical system, based on copper nanofoam accompanied by 1-butyl-3-methyl-imidazolium bromide (BMIMB) as the homogeneous co-catalyst for the electrochemical conversion of CO2 at ambient pressure and temperature was developed. Although, there have been some efforts for utilization of copper nanofoam or imidazolium-based catalysts toward the electro-reduction of CO2, evaluation of both catalysts to take advantage of the potential synergic effect of their combination would be an interesting aspect. The electro-reduction of CO2 in a CO2 saturated 0.1 M KHCO3 electrolyte was optimized based on the highest CO2 conversion efficiency in various conditions. The results show that the copper nanoporous foam, deposited for 45 s with the contribution of 40 mM BMIMB at -1.6 V vs. Ag/AgCl would effectively reduce CO2 and demonstrate a high CO2 faradaic efficiency i.e. more than 46% improvement, compared to similar previously reported experiment. The results confirm the applicability of this experiment as a developed method for efficient CO2 reduction.