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Metal−organic frameworks (MOF) are versatile and good structurally stable materials that are widely used in energy conversion and storage. In this work, rare-earth-based bimetallic metal−organic framework (NiY-BTC) nanorods anchored with transition metal−organic frameworks (ZIF-67) were used as versatile precursors to prepare novel metal/rare-earth metal oxidecoupled carbon-based bifunctional oxygen electrocatalysts (NiY/C@Co/C). Due to the stable nanorods framework structure, appropriate Y 2 O 3 active center, and richness of Co−N sites in the carbon skeletons, the NiY/C@Co/C catalyst exhibits high onset potentials (E onset = 0.928 V) and half-wave potential (E 1/2 = 0.83 V) for the oxygen reduction reaction (ORR), and expresses a low overpotential (η = 392 mV@10 mA cm −2 ) for the oxygen evolution reaction (OER). Moreover, a rechargeable Zn−air battery assembled with NiY/C@Co/C as the air cathode catalyst displayed a great specific capacity (899.6 mAh gZn −1 ) and a remarkable peak power density of 102.2 mW cm −2 , as well as excellent durability and stability. This work delivers a way using rare-earth metal− organic frameworks to get the corresponding metal oxide-coupled carbon-based bifunctional oxygen electrocatalysts for rechargeable Zn−air batteries.

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Exploring non-noble metal electrocatalysts with high activity, elevated stability, and low cost is of great significance for efficient electrochemical energy storage and conversion technologies. Herein, rare-earth metal−organic framework (LaNi-MOF)derived three-dimensional La 2 O 3 /Ni x P y nanoparticles embedded in nitrogen-doped porous carbon (La 2 O 3 /Ni x P y @NC) are rationally synthesized by a facile solvothermal method followed by pyrolysis and a low-temperature phosphating strategy. The highly conductive nitrogen-doped porous carbon and the synergistic effect between La 2 O 3 and Ni x P y nanoparticles provide abundant active catalytic sites and enhance the electron mass transfer capability, which endows the La 2 O 3 /Ni x P y @NC catalyst with excellent oxygen evolution reaction activity. Moreover, the La 2 O 3 /Ni x P y @NC catalyst provides a low overpotential (η 100 = 384 mV), which is superior to that of commercial RuO 2 (η 100 = 451 mV). More importantly, the introduction of La 2 O 3 can not only effectively adjust the electronic structure and morphology of the catalyst but also significantly improve the long-term stability and durability of the La 2 O 3 /Ni x P y @NC electrocatalyst. This work provides an efficient strategy for the future design of highly efficient catalysts enriched with rare-earth species.