Wang Dan, Zha Sujuan, Li Yaqiang, Li Xiaosong, Wang Jibiao, Chu Yuan, Mitsuzaki Naotoshi, Chen Zhidong
Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, Advanced Catalysis and Green Manufacturing Collaborative Innovation Center, School of Petrochemical Engineering, Changzhou University, Changzhou, Jiangsu 213164, China.
MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China.
J Colloid Interface Sci. 2024 Jul;665:879-887. doi: 10.1016/j.jcis.2024.03.188. Epub 2024 Mar 29.
Iron-nitrogen-carbon single-atom catalysts derived from zeolitic-imidazolate-framework-8 (ZIF-8) have presented its great potential for the oxygen reduction reaction (ORR) in Zn-air batteries (ZABs). However, due to insufficient active Fe-N sites, its ORR activity is inferior to Pt-based catalysts. Herein, a carboxylate (OAc) linker strategy is proposed to design a ZIF-8-derived FeNCOAc catalyst with abundant accessible Fe-N single-atom sites. Except that imidazole groups can coordinate with Fe ions, the OAc linker on the unsaturated coordination Zn nodes can anchor and coordinate with more Fe ions, resulting in a significant increase in Fe-N site density. Meanwhile, the corrosion of carbon skeleton by OAc oxidation during heat-treatment leads to improved porosity of catalyst. Benefitting from the highly dense Fe-N sites and hierarchical pores, the FeNCOAc endows superior performance in alkaline medium (E = 0.906 V), which is confirmed by density functional theory calculation results. Meanwhile, the assembled liquid ZAB delivers a favorable peak power density of 173.9 mW cm, and a high specific capacity of 770.9 mAh g as well as outstanding durability. Besides, the solid-state ZAB also shows outstanding discharge performance.
源自沸石咪唑酯骨架-8（ZIF-8）的铁氮碳单原子催化剂在锌空气电池（ZAB）的氧还原反应（ORR）中展现出巨大潜力。然而，由于活性铁氮位点不足，其ORR活性低于铂基催化剂。在此，提出一种羧酸盐（OAc）连接策略来设计具有丰富可及铁氮单原子位点的ZIF-8衍生的FeNCOAc催化剂。除了咪唑基团可与铁离子配位外，不饱和配位锌节点上的OAc连接体可锚定并与更多铁离子配位，导致铁氮位点密度显著增加。同时，热处理过程中OAc氧化对碳骨架的腐蚀导致催化剂孔隙率提高。受益于高密度的铁氮位点和分级孔隙，FeNCOAc在碱性介质中表现出优异性能（E = 0.906 V），这得到密度泛函理论计算结果的证实。同时，组装的液流ZAB具有173.9 mW cm的良好峰值功率密度、770.9 mAh g的高比容量以及出色的耐久性。此外，固态ZAB也表现出出色的放电性能。
