Carbon nanotubes cross-linked Fe/Fe3C nanoparticles and Fe single atoms as high-efficiency bifunctional oxygen electrocatalyst for rechargeable zinc-air batteries

Although zinc-air batteries (ZABs) have made great progress in recent years, there still a great challenge to develop low-cost bifunctional electrocatalysts with high catalytic activity and stability. Herein, we report a bifunctional oxygen electrocatalyst consisting of ZIF-derived carbon-anchored Fe/Fe 3 C nanoparticles and Fe single atoms, which are crosslinked by carbon nanotubes (denoted as CNT@Fe/Fe 3 C||FeNC). Benefiting from the synergetic effect of Fe/Fe 3 C nanoparticles, Fe-N 4 active sites, and the 3D interpenetrating network structure, CNT@Fe/Fe 3 C||FeNC shows excellent bifunctional catalytic activities with a low ΔE of 0.671 V. Furthermore, the assembled rechargeable ZAB demonstrates a high peak power density of 187 mW cm –2 and shows excellent cycling stability up to 600 h This work provides new ideas for constructing non-precious metal bifunctional catalysts for practical applications in ZABs.