Balancing Electronic Spin State via Atomically-Dispersed Heteronuclear Fe-Co Pairs for High-Performance Sodium-Sulfur Batteries
Li, Canhuang (Universitat de Barcelona. Departament de Química)
Yu, Jing (Institut Català de Nanociència i Nanotecnologia)
Yang, Dawei (Henan University)
Li, Hao (Institut de Recerca en Energia de Catalunya)
Cheng, Yapeng (Institut de Recerca en Energia de Catalunya)
Ren, Yuchuan (Institut de Recerca en Energia de Catalunya)
Bi, Xiaoyu (Institut de Recerca en Energia de Catalunya)
Ma, Jiachen (Chemnitz University of Technology. Research Center for Materials, Architectures and Integration of Nanomembranes)
Zhao, Ruirui (Hua nan shi fan da xue)
Zhou, Yingtang (Zhejiang Ocean University)
Wang, Jian (Helmholtz Institute Ulm)
Huang, Chen (Universitat de Barcelona. Departament de Química)
Li, Junshan (Chengdu University. Institute for Advanced Study)
Pinto-Huguet, Ivan (Institut Català de Nanociència i Nanotecnologia)
Arbiol i Cobos, Jordi (Institut Català de Nanociència i Nanotecnologia)
Zhang, Haining (Wuhan University of Technology)
Xin, Sen (Chinese Academy of Sciences. Institute of Chemistry)
Cabot i Codina, Andreu (Institut de Recerca en Energia de Catalunya)

Date:	2025
Abstract:	Room-temperature sodium-sulfur (Na-S) batteries are emerging as a promising next-generation energy storage technology, offering high energy densities at low cost and utilizing abundant elements. However, their practical application is hindered by the shuttle effect of sodiumpolysulfides and the sluggish kinetics of sulfur redox reactions. In this study, we demonstrate a heteronuclear diatomic catalyst featuring Fe and Co bimetallic sites embedded in nitrogendoped hollow carbon nanospheres (Fe-Co/NC) as an effective sulfur host at the cathode of NaS batteries. Aberration-corrected high-angle annular dark field scanning transmission electron microscopy demonstrates the presence of isolated Fe-Co atomic pairs, while synchrotron radiation X-ray absorption fine structure analysis confirms the (Fe-Co-N₆) coordination structure. Density functional theory calculations show that the introduction of Fe atoms induces electron delocalization in Co(II), shifting the electronic configuration from a low-spin to a higher-spin state. This shift enhances the hybridization of the Co dz² orbitals with the antibonding π orbitals of sulfur atoms within the sodium sulfide species that accelerates their catalytic conversion. As a result, Fe-Co/NC-based cathodes exhibit excellent cycling stability (378 mAh g-1 after 2000 cycles) and impressive rate performance (341. 1 mAh g-1 under 5 A g-1).
Grants:	Agencia Estatal de Investigación PCI2022-132985 Generalitat de Catalunya 2021/SGR-01581 Generalitat de Catalunya 2021/SGR-00457 Agencia Estatal de Investigación CEX2021-001214-S
Note:	Altres ajuts: CERCA Programme/Generalitat de Catalunya
Rights:	Aquest material està protegit per drets d'autor i/o drets afins. Podeu utilitzar aquest material en funció del que permet la legislació de drets d'autor i drets afins d'aplicació al vostre cas. Per a d'altres usos heu d'obtenir permís del(s) titular(s) de drets.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Electronic spin state ; Energy storage technologies ; Heteronuclear ; Higher energy density ; Low-costs ; Na/S batteries ; Orbitals ; Performance ; Polysulphides ; Sodium-sulfur batteries
Published in:	Journal of the American Chemical Society, Vol. 147, Num. 10 (March 2025) , p. 8250-8259, ISSN 1520-5126

DOI: 10.1021/jacs.4c15408

Postprint 23 p, 1.8 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles