FeCoS2 polyhedral spherical nanoparticle decorated nitrogen doped hollow carbon nanofibers as high-performance self-supporting anodes for K-ion storage

• Published in: Dalton transactions : an international journal of inorganic chemistry 2022-11, Vol.51 (42), p.16126-16134
• Main Authors: Xu, Haoshan, Huang, Shuhong, Yang, Yang, Chen, Jintao, Liang, Lingxun, Zhang, Jun, Li, Ling, Zhao, Xiaohui, Zhang, Wenming
• Format: Article
• Language: English
• Subjects: Anodes; Carbon fibers; Electrochemical analysis; High temperature; Ion storage; Nanocomposites; Nanofibers; Nanoparticles; Nitrogen; Potassium; Rechargeable batteries; Structural stability
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d2dt02832h

Herein, we present a freestanding and flexible 3D nanocomposite made of polyhedral spherical FeCoS2 and nitrogen-doped hollow carbon nanofibers (FeCoS2@N-HCNFs) that is synthesized through coaxial electrospinning, high-temperature calcination, and a facile solvothermal process. As a binder-free anode composite for potassium-ion batteries (PIBs), FeCoS2@N-HCNF presents a high specific discharge capacity on the first lap (701.2 mA h g−1 at 100 mA g−1) and superior cycling stability (132.6 mA h g−1 at 3200 mA g−1 after 600 cycles). The impressive electrochemical performance can be ascribed to the unique 3D structure, such as the enormous specific surface area of the mesoporous structure beneficial for K+ transfer, the three-dimensional hollow carbon nanofiber scaffold enhances the structural stability, and polyhedral spherical FeCoS2 improves the overall specific capacity. According to the above description, the FeCoS2@N-HCNF anode is a promising candidate for advanced potassium-ion batteries.