Unveiling the Dynamic Evolution of Catalytic Sites in N-Doped Leaf-like Carbon Frames Embedded with Co Particles for Rechargeable Zn–Air Batteries
Yuebin Lian,
Weilong Xu,
Xiaojiao Du,
Yannan Zhang,
Weibai Bian,
Yuan Liu,
Jin Xiao,
Likun Xiong,
Jirong Bai
Affiliations
Yuebin Lian
School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213032, China
Weilong Xu
School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213032, China
Xiaojiao Du
School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213032, China
Yannan Zhang
School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213032, China
Weibai Bian
School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213032, China
Yuan Liu
School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China
Jin Xiao
School of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213032, China
Likun Xiong
School of Chemistry and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China
Jirong Bai
Research Center of Secondary Resources and Environment, School of Chemical Engineering and Materials, Changzhou Institute of Technology, Changzhou 213032, China
The advancement of cost-effective, high-performance catalysts for both electrochemical oxygen reduction reactions (ORRs) and oxygen evolution reactions (OERs) is crucial for the widespread implementation of metal–air batteries. In this research, we fabricated leaf-like N-doped carbon frames embedded with Co nanoparticles by pyrolyzing a ZIF-L/carbon nanofiber (ZIF-L/CNF) composite. Consequently, the optimized ZIF-L/CNF-700 catalyst exhibit exceptional catalytic activities in both ORRs and OERs, comparable to the benchmark 20 wt% Pt/C and RuO2. Addressing the issue of diminished cycle performance in the Zn–air battery cycle process, further detailed investigations into the post-electrolytic composition reveal that both the carbon framework and Co nanoparticles undergo partial oxidation during both OERs and ORRs. Owing to the varying local pH on the catalyst surface due to the consumption and generation of OH− by OERs and ORRs, after OERs, the product is reduced-size Co particles, while after ORRs, the product is outer-layer Co(OH)2-enveloping Co particles.
