ИСТИНА

Electrocatalytic conversion of carbon dioxide (CO2) into gaseous and liquid fuels has a great potential. However, significant conceptual and technological advances are still needed to make this process economically viable. Most studies on CO2 electroreduction were carried out using aqueous electrolytes. The solubility of CO2 in water is rather low, which leads to an undesirably low rate of mass transfer to the cathode. The use of non-aqueous electrolytes has the advantage of a significant increase in the CO2 solubility and allows avoiding intensive hydrogen evolution. In this work, we investigate electrocatalytic activity of Au, Pt, Cu electrodes single crystal electrodes in electroreduction of CO2 in aprotic solvents, such as acetonitrile and propylene carbonate [1], as well as in aqueous solutions. We demonstrate that the CO2 reduction is a structure sensitive reaction under these conditions. The highest catalytic activity was found for (110) surfaces among other basal faces of fcc single crystals. The effect of addition of water on the kinetics and mechanism of CO2 reduction is also explored. Moderate amounts of water (≤ 1 M) in aprotic media leads to a drastic change in CO2 electroreduction kinetics. [1] A. Rudnev, M. Ehrenburg, E. Molodkina, I. Botriakova, A. Danilov, T. Wandlowski, Electrocatalysis, 6 (2015) 42-50.