Oxygen reduction and evolution on perovskite - based nanocomposites

Advanced materials that form functional domains in the nanometer size range are envisaged for the development of highly efficient systems for energy storage and production. Transition metal oxides with the perovskite structure are among the best non platinum catalysts operating in alkaline medium, and potential candidates as bi-functional catalysts for the air electrode of rechargeable metal-air batteries or of regenerative fuel cells. However, perovskites have typically low specific surface area and poor electrical conductivity at near room temperature. In this work, we will present our recent results on the synthesis and electrochemical characterization of perovskites based nanocomposites (i) prepared by combining soft and hard template method [1] to increase the materials’ specific surface area, and (ii) synthesized in the presence of a carbon source to enhance the electrical conductivity of the nanoparticles. The effect of the perovskites’ textural properties and composition on their electrocatalytic activity towards oxygen evolution and reduction reactions will be discussed. [1] F. Deganello, M.L. Testa, V. La Parola, A. Longo, A.C. Tavares, LaFeO3-based nanopowders prepared by a soft-hard templating approach: the effect of silica texture" Journal of Materials Chemistry A, A (2) 22, 2014, 8483-8447. Acknowledgements The authors acknowledge the Italian National Research Council (STM 2014, “Bifunctional perovskite-carbon nanocomposites for Zn-air batteries”), NSERC (Discovery grant) and FQRNT (Nouveaux chercheurs - équipment) for the financial support.