Multiligand Coordination Self-Assembly Bimetallic Complex Derived Fexc Decorate Fe and N Co-doped Carbon Nanotube for Highly Efficient Oxygen Reduction Reaction

Abstract

Iron carbides assisted Fe-N-C electrocatalysts have attracted significant attention as promising candidates to enhance intrinsic activity in the oxygen reduction reaction (ORR), offering a viable alternative for Pt-based catalysts. However, their widespread development is impeded by challenges such as uncontrolled aggregation, the formation of large nanoparticles, and inefficient synthesis processes. Herein, we report a multiligand coordination self-assembly strategy to synthesize a novel metal-organic framework (MOF) precursor (FeZn-PBMI) with dual ligands and dual metals, followed by a thermal polymerization self-assembly process that successfully prepared the coexistence of FeNx sites and FexC atomic clusters decorate N-doped carbon nanotubes (FexC@FeNCNTs) in gram-scale quantities. The ordered distribution of Zn and Fe within the FeZn-PBMI effectively prevents Fe aggregation during high-temperature pyrolysis, resulting in uniformly dispersed approximately 10 nm FexC nanoparticles. As expected, the FexC@FeNCNTs composite exhibits superior ORR performance with a half-wave potential of 0.87 V, surpassing commercial Pt/C (0.85 V), and demonstrates excellent long-term stability in Zn-air batteries with 1000 cycles. This synthetic approach may facilitate the development of highly active catalysts, advancing the practical application of Fe-N-C catalysts in various energy-related technologies.