Fig. 5: DFT calculations.

a Proposed reaction pathway of oxygen evolution reaction on Ir SAs/NiO. b Free energy diagrams of OER on Ir SAs/NiO (100), NiO (100), and IrO₂ (110) at 1.23 V vs. RHE. Charge transfer diagrams of c Ir SAs/NiO, d NiO, e IrO₂ during OER.