Coordination engineering and electronic structure modulation of FeNi dual-single-atoms encapsulated in N, P-codoped 3D hierarchically porous carbon electrocatalyst for synergistically boosting oxygen reduction reaction

• Published in: Applied catalysis. B, Environmental Environmental, 2024-08, Vol.351, p.123991, Article 123991
• Main Authors: Zhang, Lu, Wu, Dong-Hui, Haq, Mahmood Ul, Feng, Jiu-Ju, Yang, Fa, Wang, Ai-Jun
• Format: Article
• Language: English
• Subjects: Bimetallic single-atoms; Doped porous carbon; Oxygen reduction reaction; Pyrolysis; Zinc-air batteries
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2024.123991

With the increasing energy and environmental issues in recent years, it is vital to explore inexpensive and highly activated oxidation reduction reaction (ORR) catalysts for next generation energy storage and conversion devices such as zinc-air batteries. Herein, FeNi dual-single-atoms were efficiently encapsulated into N,P-codoped 3D hierarchically porous carbon (FeNi DSAs/N,P-PC) by a simple one-step pyrolysis. The resulting FeNi DSAs/N,P-PC catalyst exhibited the better ORR activity with the positive onset potential (Eonset = 1.02 V) and half-wave potential (E1/2 = 0.88 V) over commercial Pt/C, and performed well in the assembled zinc-air batteries (peak power density of 124.73 mW cm−2,and long-term charge/discharge stable cycling for 330 h). The XAFS analysis clearly displayed the coordination structure and interactions of the FeNi dual atoms. The DFT calculations show that P-O bonds have great influence on the electronic structure of the FeNi dual atoms. And Ni site can effectively modulate the electronic structure of the Fe site to promote charge transfer and further reduce the energy barrier of the rate-limiting step. This strategy provides a viable strategy for development of low-cost high-performance transition metal diatomic catalysts suitable for energy conversion and storage devices. [Display omitted] •FeNi dual single-atoms/N, P-doped porous carbon was prepared by a simple pyrolysis strategy.•Three-dimensional layered structure exposed more active sites.•Heteroatom doping effectively increased intrinsic catalytic activity and stability, inhibiting the agglomeration.•The FeNi dual-single-atom electrocatalyst displayed excellent ORR catalytic performance over Pt/C.•The as-assembled Zn-air battery exhibited high open-circuit voltage, large power density and long-term durability.