The lack of stability of critical raw material-free electrocatalysts during the oxygen evolution reaction in acidic electrolytes lies beneath the use of Ir-based electrocatalysts in polymeric water electrolysis. Here, a strategy to enhance γ-MnO2 stability in acid is proposed. Theoretical and spectroscopic approaches reveal that increasing the fraction of O atoms in the appropriate position, namely Opla, prevents Mn dissolution during water electrolysis.