The rational design of non-precious transition metal perovskite oxide catalysts holds exceptional promise for understanding and mastering the kinetics of oxygen electrocatalysis instrumental to artificial photosynthesis, solar fuels, fuel cells, electrolyzers, and metal–air batteries.

This work experimentally identifies the charge-transfer energy as a key factor governing the catalytic oxygen evolution reaction (OER) activity and mechanism across a wide range of perovskite chemistries.