FeCo Bimetallic ZIF Derivatives Decorated with CoFe‐LDH to Promote Bifunctional Oxygen Electrocatalysis Activation

Abstract Reasonably screening the targeted oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) constituents and constructing high‐efficiency and stabilized ORR/OER bifunctional electrocatalysts are pivotal for the advancement of rechargeable zinc‐air batteries (ZABs). Here, CoFe layered double hydroxide (CoFe‐LDH) nanosheets are deposited on nitrogen‐doped graphite‐carbon polyhedra with FeCo alloy nanoparticles (FeCo/LDH‐NGCP). Due to the synergic effect between FeCo‐NGCP, CoFe‐LDH and FeCo/LDH‐NGCP, the electrocatalyst with the abundant and accessible active sites can provide good charge/mass transfer, and thus shows wonderful ORR and OER bifunctional electrocatalytic performance. In ORR tests, FeCo/LDH‐NGCP catalyst displays larger half‐wave potential (E1/2, 0.89 V vs. 0.85 V), higher limiting current density (JL, 5.91 mA/cm2 vs. 5.14 mA/cm2) and better stability than commercial Pt/C. As for OER, FeCo/LDH‐NGCP possesses a smaller overpotential (η) of 299.6 mV at a current density of 10 mA/cm2 and more durable stability than commercial RuO2 (330.6 mV). Furthermore, in ZAB tests, the cycling stability of ZAB‐FeCo/LDH‐NGCP (over 470 h) outperforms the ZAB‐Pt/C+RuO2 (92 h) with commercial electrocatalyst (Pt/C+RuO2). Therefore, the FeCo/LDH‐NGCP catalyst offers a new perspective to construct ZABs bifunctional catalysts and their commercial application in ZABs.