Bio-Inspired Design of Hierarchically Porous ZIF-8 Derived Fe-N-C Bifunctional Catalysts for Enhanced Zinc-Air Battery Performance
Abstract
Zeolitic Imidazolate Frameworks (ZIF-8) has emerged as promising candidate for alleviating the aggregation of Fe3N-catalysts, exhibiting significantly improved oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) for rechargeable zinc-air batteries. To further improve the catalytic performance, it is crucial to fabricate ZIF-8 with hierarchically porous structures, which remains challenging due to the rapid crystallization kinetics and the weak interactions. Inspired by biological porous materials, we developed a novel method using 1,3,5-trimethylbenzene TMB as a mediating molecule to dynamically regulate the organic-inorganic interface between templates and ZIF-8 precursors, achieving the micro-meso-macropores of ZIF-8, which synergistically enhances mass transport and active site accessibility. Additionally, TMB preserves the weakly alkaline environment required for ZIFs’ structural integrity by leveraging its hydrophobic co-solvent effect. The as-synthesized Fe3N-HPZIF-8 catalyst integrates Fe3N active sites, hierarchically porous structures, and pyrrolic-N dopants, resulting in the exceptional bifunctional activity in alkaline media ($Δ$E = 0.619 V), exceeding most benchmark catalysts. When integrated into zinc-air batteries, a peak power density of 205.2 mW cm-2 is achieved. This work presents a generalizable synthetic approach for high-performance metal-air battery catalysts.
Weimin Wang
Chief Professor
Chief Professor and Doctoral Supervisor at Wuhan University of Technology.
Zhengyi Fu
Academician of the Chinese Academy of Engineering
Academician of the Chinese Academy of Engineering, Professor at Wuhan University of Technology.
Zhaoyong Zou
Professor
My research interests include bioprocess inspired fabrication, crystallization and ceramics.