Perovskite oxides are demonstrated for the first time as efficient electrocatalysts for the hydrogen evolution reaction (HER) in alkaline solutions. A-site praseodymium-doped Pr0.5 (Ba0.5 Sr0.5 )0.5 Co0.8 Fe0.2 O3- δ (Pr0.5BSCF) exhibits dramatically enhanced HER activity and stability compared to Ba0.5 Sr0.5 Co0.8 Fe0.2 O3- δ (BSCF), superior to many well-developed bulk/nanosized nonprecious electrocatalysts. The improved HER performance originates from the modified surface electronic structures and properties of Pr0.5BSCF induced by the Pr-doping.

The perovskite SrNb0.1 Co0.7 Fe0.2 O3-δ (SNCF) is a promising OER electrocatalyst for the oxygen evolution reaction (OER), with remarkable activity and stability in alkaline solutions. This catalyst exhibits a higher intrinsic OER activity, a smaller Tafel slope and better stability than the state-of-the-art precious-metal IrO2 catalyst and the well-known BSCF perovskite. The mass activity and stability are further improved by ball milling. Several factors including the optimized eg orbital filling, good ionic and charge transfer abilities, as well as high OH(-) adsorption and O2 desorption capabilities possibly contribute to the excellent OER activity.

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A synergistic co‐doping strategy is proposed to identify a series of BaCo0.9–xFexSn0.1O3–δ perovskites with tunable electrocatalytic activity for the oxygen evolution reaction (OER). Simply through tailoring the relative concentrations of less OER‐active tin and iron dopants, a cubic perovskite structure (BaCo0.7Fe0.2Sn0.1O3–δ) is stabilized, showing intrinsic OER activity >1 order of magnitude larger than IrO2 and a Tafel slope of 69 mV dec−1.

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