Электрокаталитическое окисление метанола на тернарных сплавах кобальта

Abstract

Electrolytic coatings ternary Co-Mo-W and Co-Mo-Zr alloys, deposited from complex pyrophosphate-citrate electrolytes, are distinguished by a uniformly developed surface, the relief and degree of development of which are favorable for the realization of catalytic processes. Electrocatalytic oxidation of methanol, as an energy-consuming fuel cell reagent, on the electrodes of these alloys is characterized by the presence a single wave with a clearly defined limiting current. The activity of electrodes with ternary coatings in the oxidation of methanol is significantly higher than that of platinum, and for the Co-Mo-Zr alloy, the peak height is 2-2.5 times than for Co-Mo-W. The increased catalytic activity of the coatings is due to both a high degree of surface development and the synergistic effect of alloying metals. The combination of kinetic criteria indicates the irreversible electrocatalytic oxidation of methanol on the studied alloys in the mixed kinetics mode through the stage of adsorption of the reactant. Ternary coatings have a high corrosion resistance in alkaline media and, by the value of the deep corrosion index, are very resistant. The high catalytic activity and corrosion resistance of the Co-Mo-W and Co-Mo-Zr alloys make it possible to consider them as promising materials for the electrochemical power industry, including for red-ox flow batteries and fuel cells.