Electrochemical reconstruction typically generates powerful active sites for the oxygen evolution reaction (OER). However, engineering effective reconstruction strategies to manipulate the in situ formation of desired catalytically active surfaces, generate powerful active sites, and enhance their catalytic performance remains a challenge. Herein, leveraging the oxidation-potential-assisted precipitation etching, a heterostructure of NiFeOOH/NiFe phosphate was meticulously engineered to achieve highly efficient OER. During the electrochemical reconstruction, the leaching of inactive PO