Electroreduction of CO on Polycrystalline Copper at Low Overpotentials

Cu is the only monometallic electrocatalyst to produce highly reduced products from CO2 selectively because of its intermediate binding of CO. We investigate the performance of polycrystalline Cu for the electroreduction of CO in alkaline media (0.1 M KOH) at low overpotentials (−0.4 to −0.6 V vs RHE). We find that polycrystalline Cu is highly active at these potentials. The overall CO reduction rates are comparable to those of the nanostructured forms of the material, albeit with a distinct product distribution. While nanostructured forms of Cu favor alcohols, polycrystalline Cu produces greater amounts of C2 and C3 aldehydes, as well as ethylene.