Co-doping strategy for developing perovskite oxides as highly efficient electrocatalysts for oxygen evolution reaction

The design of cost-effective and highly efficient catalysts for a wide range of electrochemical energy storage applications remains a key element in the societal pursuit of sustainable energy. [1-3] In particular, the electrocatalytic splitting of water to generate hydrogen and oxygen enables the storage of a large amount of energy. [4-6] However, the oxygen evolution reaction (OER) at the anode of a water electrolyzer is kinetically hampered by a complex four-electron oxidation process and therefore requires a considerable overpotential () that could cause significant losses to the overall efficiency of water splitting. To afford fast kinetics and low overpotential in practical applications, noble metal oxide catalysts (e.g., IrO 2 and RuO 2) are often involved, [7,8] but the high cost and scarcity of precious metals hinder their large-scale use. Furthermore, these precious-metal catalysts suffer from poor durability over long-term operations. [9-11] Therefore, it is of prime importance to develop low-cost and earth-abundant alternatives with comparable or even better catalytic activity and improved stability than stateof-the-art precious metal catalysts to achieve energy production on a large scale.