Ionic Liquid as the C and N Sources to Prepare Yolk-shell Fe3O4@N-doped Carbon Nanoparticles and its High Performance in Lithium-ion Battery

• Published in: Electrochimica acta Vol. 190; pp. 797 - 803
• Main Authors: Yang, Liu, Guo, Guannan, Sun, Huajun, Shen, Xiudi, Hu, Jianhua, Dong, Angang, Yang, Dong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2016
• Subjects: Anode material; Fe3O4 nanoparticle; Ionic liquid; Lithium-ion battery; Yolk-shell; Anode material; Lithium-ion battery; Yolk-shell; Fe3O4 nanoparticle; Ionic liquid
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2016.01.028

[Display omitted] Transition metal oxide is a promising anode material in lithium-ion battery, however it suffers from poor cycling performance due to its large volume change during charge/discharge process. Herein, we designed and fabricated a yolk-shell Fe3O4 composite nanoparticle with individual Fe3O4 nanoparticle as the yolk and N-coped carbon as the shell by using ionic liquid as the C and N sources. The individual Fe3O4 nanoparticle was firstly covered by a sacrificial SiO2 layer, then coated with N-doped carbon by one-step carbonization with ionic liquid (3-cyanopyridine/H2SO4). After removing the SiO2 layer by NaOH etching, yolk-shell Fe3O4@void@N-doped carbon was obtained. This unique structure would not only afford adequate void to accommodate the large volume change during charge/discharge process, but also improve the structural stability and electrical conductivity. Thus, Fe3O4@void@N-doped carbon showed a high reversible capacity and cycling life of 860mAhg−1 after 500 charge/discharge cycles at a current rate of 1000mAg−1, and excellent rate capacity of 180mAhg−1 even at 7000mAg−1.