Efficiency boost of electrochemical energy conversion by bifunctional catalysis

Abstract:
The increased demand for energy in recent decades and the depletion of fossil fuel reserves have led to the need for new and clean power sources that will be used in the future. There are various proposed alternatives to technologies based on fossil fuels, but one of the most popular is use of electrochemical energy conversion and storage devices.

However, the design of efficient electrocatalysts for these devices represents a great challenge for the scientific community. Our research is focused on the development of bifunctional catalysts based on transition metal oxides (Mn, Ni, and Ti) for oxygen reduction and evolution of oxygen in an alkaline environment.

These two reactions are the limiting factor in the functioning of electrochemical devices due to their slow kinetics on most electrode materials. Designing bifunctional electrocatalysts necessary for the operation of metal-air batteries and regenerative fuel cell devices that combine a fuel cell and an electrolytic cell represents a special challenge - the same material should possess high activity and stability under both cathodic and anodic polarization conditions.

The results obtained so far show an excellent performance of catalysts on transition metal oxides decorated with platinum, where activity similar to that of commercial Pt/C was achieved with half the amount of platinum in the synthesized electrocatalysts. Besides high activity, these materials also showed greater stability than conventional carbon-supported electrocatalysts.