Atmosphere‐Regulated Pyrolysis Switches ORR Pathway on Iron‐Based Catalyst for H ₂ O ₂ Synthesis and Zn‐Air Batteries

Developing simple methods to achieve flexible regulation of oxygen reduction reaction (ORR) selectivity is essential for sustainable energy technologies, yet remains challenging. An effective strategy for directing ORR selectivity through pyrolysis atmosphere is proposed using [Fe(TPDC) ₂ (BIB) ₂ ] _n (FeMOF, TPDC = 3, 4‐thiophenedicarboxylic acid; BIB = 1, 4‐bis(3‐imidazolyl)‐benzene) as the precursor. Notably, Fe ₂ O ₃ derived from air pyrolysis exhibits high two‐electron (2e ⁻ ) ORR selectivity for hydrogen peroxide (H ₂ O ₂ ) production, achieving a rate of 0.99 mol g ⁻¹ h ⁻¹ , whereas Fe and Fe ₃ C encapsulated in nitrogen‐doped carbon nanotubes (Fe/Fe ₃ C@NCNTs) from N ₂ ‐pyrolysis demonstrates high‐efficiency four‐electron (4e ⁻ ) ORR selectivity ( E _1/2 = 0.92 V vs. RHE), exceeding Pt/C. Fe/Fe ₃ C@NCNT‐based cathode enabled zinc‐air batteryz (ZAB) to achieve exceptional peak power density and remarkable cycle stability. Theoretical calculations indicate that the binding strength of the *OOH intermediate governs ORR selectivity. Simple atmosphere adjustment during the pyrolysis process enables on‐demand optimization of electrocatalyst ORR selectivity, demonstrating MOF potential in electrocatalysis and providing new perspectives for designing low‐cost, efficient non‐noble metal catalysts.