One-pot co-precipitation synthesis of Fe3O4 nanoparticles embedded in 3D carbonaceous matrix as anode for lithium ion batteries

• Published in: Journal of materials science 2019-03, Vol.54 (5), p.4212-4224
• Main Authors: Ai, Qing, Yuan, Zewei, Huang, Renzhong, Yang, Canxing, Jiang, Guodong, Xiong, Jian, Huang, Zhen, Yuan, Songdong
• Format: Article
• Language: English
• Subjects: Carbon; Carbonization; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Collapse; Coprecipitation; Crystallography and Scattering Methods; Electron transfer; Energy Materials; Iron oxides; Lithium; Lithium-ion batteries; Materials Science; Nanoparticles; Polymer Sciences; Rechargeable batteries; Scanning electron microscopy; Solid Mechanics; Transmission electron microscopy
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-018-3141-3

Fe 3 O 4 @C nanoparticles with a 3D net-like structure were synthesized via a facile and scalable one-pot co-precipitation followed by a subsequent carbonization in an Ar atmosphere. Verified by scanning and transmission electron microscopy characterization, it can be seen that Fe 3 O 4 nanoparticles with the size of 10–15 nm were embedded in a uniform carbon shell with a thickness of around 2 nm. Furthermore, the corresponding XRD and EDS analysis combined with TEM images also proved that the thin carbon layer on the nano-scale Fe 3 O 4 was amorphous. The charge/discharge tests showed that Fe 3 O 4 @C composite delivered an excellent reversible capacity of 980 mAh g −1 after 100 cycles at a current density of 92.4 mA g −1 , which was much higher than that of the pure Fe 3 O 4 (170 mAh g −1 ) synthesized by the same method. The outstanding reversible capacity is attributed to the small size of Fe 3 O 4 particles and the high conductivity and mechanical strength of the amorphous carbon layer, which accelerates the electron transfer and relieves structure collapse caused by mechanical stress, thus maintaining a superior electrochemical stability.