Interface N‐Doped Carbon Layer Modulation on MgAl 2 O 4 via Coal‐Tar‐Based Supercrosslinked Polymer for Efficient Oxygen Reduction Electrocatalysis

ABSTRACT Coal tar pitch (CTP), a byproduct of coal chemical industries, requires novel strategies to enhance its value. Advancement of high activity and steady non‐precious metal oxygen reduction reaction (ORR) electrocatalysts based on low‐cost carbon precursors has emerged as a critical research direction. In this study, a strategy is reported for converting inactive MgAl 2 O 4 into a novel and high‐performance ORR catalyst MgAl 2 O 4 ‐HCPs. MgAl 2 O 4 ‐HCPs is designed via the pyrolysis of coal tar‐based hyper‐crosslinked polymers (HCPs) that are composited using the Friedel–Crafts alkylation reaction, with MgO serving as the template. Nitrogen doping serves as a catalyst to induce the abundant generation of oxygen vacancies, which synergistically interact with the porous carbon matrix to jointly regulate and significantly enhance the intrinsic catalytic activity on the spinel surface. MgAl 2 O 4 ‐HCPs show exceptional ORR activity with a half‐wave potential of 0.882 V (vs. RHE) and is used as cathode material in zinc‐air batteries (ZABs), achieving a peak power density of 174.06 mW cm −2 . This study not only provides an innovative plan for the design of cost‐effective spinel‐type oxide electrocatalysts but also paves the way for the efficient utilization of coal tar as a valuable resource.