Sandwich structure of graphene-protected silicon/carbon nanofibers for lithium-ion battery anodes

• Published in: Electrochimica acta Vol. 210; pp. 53 - 60
• Main Authors: Chen, Yanli, Hu, Yi, Shen, Zhen, Chen, Renzhong, He, Xia, Zhang, Xiangwu, Zhang, Yan, Wu, Keshi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 20.08.2016
• Subjects: lithium-ion batteries; reduced graphene oxide; Sandwich structure; silicon/carbon nanofiber membrane; reduced graphene oxide; lithium-ion batteries; Sandwich structure; silicon/carbon nanofiber membrane
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2016.05.086

[Display omitted] •Electrospun silicon/carbon nanofibers were coated by reduced graphene oxide (rGO).•The rGO layer prevented Si exfoliation, and thus, deterioration.•It also maintained structural integrity and improved electrochemical conductivity.•The specific capacity for the electrode was 1055.1mAhg−1 after 130 cycles. Novel sandwich-structured silicon-based anodes have been prepared to inhibit the fragmentation of silicon electrodes typically caused by the large volume changes that occur during charge/discharge processes. An electrostatic self-assembly method and hydrothermal dehydration are used to introduce a reduced graphene oxide layer (rGO) on the surface of silicon/carbon nanofibers (Si/CNFs), which prevent the exfoliation of nano-Si from the electrode bulk to the liquid electrolyte, reduce the electric contact loss, stabilize the electrode’s structural integrity, and improve electrochemical conductivity. The Si/CNFs@rGO exhibit superior electrochemical performance as an anode, retaining a high specific capacity of 1055.1mAhg−1 up to 130 cycles at 0.1Ag−1, with slight capacity loss. The Si/CNFs@rGO electrode also demonstrates outstanding rate behavior with a reversible capacity of 358.2mAhg−1 at 5Ag−1. Results indicate that the graphene layer significantly improves the electrochemical performance of the silicon/carbon nanofiber electrode.