Electrochimica Acta, Vol.245, 448-454, 2017
Graphene/ZnO/Cu2O electrocatalyst for selective conversion of CO2 into n-propanol
In this work, Graphene (GN)/ZnO/Cu2O electrodes were fabricated and tested for CO2 electroreduction in 0.5 M NaHCO3 electrolyte. The XRD, FESEM, and XPS results confirm the successful synthesis of the Cu(I) oxide and ZnO composites at low temperature 34 degrees C, using simple wet-chemical approach. Linear sweep voltammetry and potentiostatic experiments were carried out for the GN/ZnO/Cu2O catalyst coated on Cu foil. In CO2 saturated electrolyte, the cathodic current density of the catalyst shows significant increase from similar to 4 mA/cm(2) for GN/ZnO to similar to 8 mA/cm(2) for GN/ZnO/Cu2O at similar to 1.8 V vs. Ag/AgCl, and the largest current density value was obtained for catalyst with a ZnO/Cu2O weight ratio of 1:2. The CO2 electroreduction on the GN/ZnO/Cu2O catalyst mainly produced n-propanol in the liquid product fraction. The maximum Faradaic efficiency for CO2 conversion to n-propanol was 30% (similar to 1.34 ppm) for GN/ZnO/Cu2O (with a ZnO/Cu2O weight ratio of 2:1) at an applied potential of similar to 0.9 V vs. Ag/AgCl. (C) 2017 Elsevier Ltd. All rights reserved.