Cu oxide/ZnO-based surfaces for a selective ethylene production from gas-phase CO2 electroconversion

Abstract In this work, the application of Cu oxides/ZnO-based electrocatalytic surfaces for the continuous and selective gas-phase electroreduction of CO2 to ethylene in a filter-press type electrochemical cell is studied. The prepared catalytic materials are characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Then, the Cu oxides/ZnO-based gas diffusion electrodes are electrochemically characterized by cyclic voltammetry and Tafel plot analyses. The ethylene formation rate and Faradaic efficiency are as high as 487.9 μmol m−2s−1 and 91.1% when a current density of 7.5 mAcm−2 (-2.5 V vs. Ag/AgCl) is applied to the system, with an ethylene/methane production ratio of 139, showing a better performance than previous electrocatalytic systems for the production of ethylene from CO2 conversion. Consequently, the use of Cu oxides/ZnO-based electrocatalysts for gas-phase CO2 reduction is a step forward in the production of C2 products, such as ethylene.