A hybrid bifunctional oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) NiCo₂O_4–x/NLG with rich pyridinic‐nitrogen‐ cobalt coordination and oxygen vacancies was synthesized via a combination of the hydrothermal method and pulsed laser irradiation. NiCo₂O_4–x/NLG exhibits an excellent catalytic activity with a low overpotential of 290 mV at 10 mA·cm^–2 for OER and a high half‐wave potential of 0.85 V for ORR. As a result, the overall ORR/OER overpotential of NiCo₂O_4–x/NLG is only 0.67 V in 1.0 mol/L KOH electrolyte, which is superior to commercial noble‐metal‐based catalysts (Pt/C+RuO₂). It is evidenced that the enhanced intrinsic OER and ORR activities of NiCo₂O_4–x/NLG are attributed to a synergistic effect between the pyridinic‐N‐Co coordination and the oxygen vacancies. This work provides a new design strategy for enhancing the intrinsic activity of bifunctional ORR/OER electrocatalysts.

中文翻译：

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具有双吡啶氮-钴和氧空位协同作用的活性杂化电催化剂，用于双功能氧的还原和释放

通过水热法和脉冲激光辐射相结合，合成了具有丰富的吡啶-氮-钴配合和氧空位的混合双功能氧还原反应（ORR）/氧释放反应（OER）NiCo ₂ O _{4– x} / NLG 。NiCo ₂ O _{4– x} / NLG具有出色的催化活性，对于OER，在10 mA·cm ^–2时具有290 mV的低过电势，对于ORR具有0.85 V的高半波电势。结果，NiCo ₂ O _{4– x}的整体ORR / OER超电势在1.0 mol / L的KOH电解质中，/ NLG仅为0.67 V，优于市售的贵金属基催化剂（Pt / C + RuO ₂）。有证据表明，NiCo ₂ O _{4– x} / NLG固有的OER和ORR活性增强归因于吡啶-N-Co配位与氧空位之间的协同作用。这项工作为增强双功能ORR / OER电催化剂的固有活性提供了一种新的设计策略。