Specific features of the oxygen reaction on catalytic systems in acetonitrile-based electrolytes

Abstract

The oxygen reaction is studied in acetonitrile solutions on various nanosystems: ХС72, 20Au/C, 20Pt/C, 15Ru/C, 20Pd/C, 20Pt10Ru/C, 20PdRu/C. It is shown that as regards their activity in the oxygen electroreduction reaction, the studied materials form the following series: Pd/C > PtRu/C > PdRu>Pt/C> Ru/C ≈ Au/C ≈ ХС72, whereas in the reaction of Li₂O₂ electrooxidation the activity series is different: Ru/C > PtRu/C > Pd/C > PdRu/C> ХС72 > Pt/C > Au/C. Assumptions are drawn on the nature of passivation for systems with the highest activity. The prospects of bimetallic catalysts (PtRu/C and PdRu/С) that combine the high activity in reactions of oxygen electroreduction and Li₂O₂ electrooxidation and also retain a considerable part of their activity on cycling are discussed. These results make it possible to judge on the possible applications of bimetallic nanosystems with bifunctional catalytic properties in lithiumoxygen fuel cells.