High efficiency graphene/Cu2O electrode for the electrochemical reduction of carbon dioxide to ethanol

Fabrication of an efficient catalyst for the electrochemical reduction of CO2 to valuable products at low overpotential remains a severe challenge. Herein, graphene (GN)/Cu2O catalyst, with an average particle size of 20-50 nm has been synthesized and coated on copper foil. The linear seep voltammetry studies showed that the 0.1 mg of GN/Cu2O loaded catalyst exhibited the highest current density in CO2 saturated 0.5 M NaHCO3 electrolyte. The GN/Cu2O electrode was significantly more active towards CO2 reduction showing a current density of approximately 12.2 mA/cm(2) at -1.7 V versus Ag/AgCl, which is higher than Cu2O electrode (8.4 mA/cm(2)). Gas chromatography-mass spectrometry analysis of the liquid products revealed that ethanol (-0.34 ppm) was found to be the predominant product at -0.9 V with high reasonably Faradaic efficiency up to 9.93%. These results suggest that graphene may be used as a promising non-metallic support for the electrochemical reduction of CO2. (C) 2016 Elsevier B.V. All rights reserved.