Wei‐Ming Zhang1,2,3, Xing‐Long Wu1,2,3, Jin‐Song Hu1,3, Yu‐Guo Guo1,3,4,5, Li‐Jun Wan1,3,4,5
1Beijing National Laboratory for Molecular Sciences (BNLMS) Beijing 100190 (PR China)
2Graduate School of CAS Beijing 100064 (PR China)
3Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, PR China
4Li-Jun Wan, Key Laboratory of Molecular Nanostructure and Nanotechnology Institute of Chemistry, Chinese Academy of Sciences (CAS) Beijing 100190 (PR China).
5Yu-Guo Guo, Beijing National Laboratory for Molecular Sciences (BNLMS) Beijing 100190 (PR China).
Tóm tắt
AbstractCarbon‐coated Fe3O4 nanospindles are synthesized by partial reduction of monodispersed hematite nanospindles with carbon coatings, and investigated with scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and electrochemical experiments. The Fe3O4C nanospindles show high reversible capacity (∼745 mA h g−1 at C/5 and ∼600 mA h g−1 at C/2), high coulombic efficiency in the first cycle, as well as significantly enhanced cycling performance and high rate capability compared with bare hematite spindles and commercial magnetite particles. The improvements can be attributed to the uniform and continuous carbon coating layers, which have several functions, including: i) maintaining the integrity of particles, ii) increasing the electronic conductivity of electrodes leading to the formation of uniform and thin solid electrolyte interphase (SEI) films on the surface, and iii) stabilizing the as‐formed SEI films. The results give clear evidence of the utility of carbon coatings to improve the electrochemical performance of nanostructured transition metal oxides as superior anode materials for lithium‐ion batteries.
