Perovskite Oxide Pr_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ as an Efficient Catalyst for Oxygen Evolution Reaction in Alkaline Media

We report a study on the catalytic performance of several typical cubic perovskite oxides Pr0.5Sr0.5Co0.8Fe0.2O3−δ, Ba0.5Sr0.5Co0.8Fe0.2O3−δ, and SrCo0.8Fe0.2O3−δ prepared by using the sol–gel method. Pr0.5Sr0.5Co0.8Fe0.2O3−δ calcined at 700 °C exhibits the lowest overpotential of 320 mV in 1 M KOH at 10 mA cm–2 and the highest mass activity of 23.84 A g–1 at 1.55 V vs. RHE, attributing to its larger surface area, better charge-transfer ability, and the optimal eg orbital electron filling. Furthermore, we also found that these several catalysts display paramagnetic- and semiconducting-like behaviors at room temperature. In short, our research expands the application of perovskite oxides in electrocatalytic oxygen evolution.