“…Electrocatalytic reduction of CO2 has been deeply studied in metal electrodes (Ag, In, Cu), gas diffusion (Ag, Pb, Pt, Cu, Ru−Pd, Ag) and in the presence of macrocyclic systems (porphyrins, phthalocyanines, tetrazamacrocycles, polypyridines) . In all cases high overpotentials are required to carry out the process, namely, between −1.0 and −2.5 V depending on experimental conditions (solvent, supporting electrolyte, temperature, pressure).…”