BC ₂ O Active Sites in Closed‐Pore B,O‐Doped Graphene Enable Selective H ₂ O ₂ Electrosynthesis

Abstract Carbon‐based electrocatalysts are promising candidates for the two‐electron oxygen reduction reaction (2e ⁻ ORR) to produce H ₂ O ₂ . However, their low activity and selectivity hinder effective application. Herein, a closed‐pore boron and oxygen co‐doped graphene (B, O‐graphene) catalysts are reported via thermal annealing of graphene oxide and boric acid under tunable H ₂ atmospheres. The optimized closed‐pore B, O‐graphene catalyst exhibits outstanding 2e ⁻ ORR performance, featuring >90% H ₂ O ₂ selectivity across a wide potential window (≥0.3 V vs Reversible Hydrogen Electrode (RHE)), a remarkable production rate of 154.7 ± 2.3 mmol g _cat ⁻¹ h ⁻¹ , and a Faradaic efficiency of ≈96% at 0.3 V versus RHE. Combined experimental and theoretical studies reveal that the BC ₂ O moieties in the closed‐pore graphene lattice, serve as the active centers, enabling exceptional selectivity.