Engineering the oxygen-evolution activity by changing the A-site rare-earth elements in RSr3Fe1.5Co1.5O10-δ (R = La, Nd, Pr) Ruddlesden-Popper perovskites

The design of high-performance and low-cost catalysts for the oxygen evolution reaction (OER) is paramount for storing and converting clean and renewable energy. Ruddlesden-Popper (RP)-structured perovskite oxides show promising potential for efficiently catalyzing the OER. In this study, a series of RP-type perovskites RSr3Fe1.5Co1.5O10-& delta; (R = La, Nd, Pr) are synthesized and investigated to correlate their structure and physical structure properties with OER activities. Among the synthesized materials, PrSr3Fe1.5Co1.5O10-& delta; shows the best OER performance, evidenced by the smallest overpotential (294 mV) as well as the lowest Tafel slope (63 mV dec(-1)). Such enhanced OER behavior is ascribed to larger electrochemically active areas, faster charge transfer rates, higher B-site valence state ions, more oxygen vacancies, and more favorable lattice oxygen oxidation (LOM) behavior. When applied in Zn-air batteries and water electrolyzers, PSFC also outperforms the benchmark catalyst RuO2, suggesting that PSFC has the potential to be an outstanding OER electrocatalyst for practical applications. This study highlights the significance of adjusting A-site elements for improving OER activities.