Nanocavity-engineered Si/multi-functional carbon nanofiber composite anodes with exceptional high-rate capacities

Zheng Long Xu, Biao Zhang, Sara Abouali, Mohammad Akbari Garakani, Jiaqiang Huang, Jian Qiu Huang, Elham Kamali Heidari, Jang Kyo Kim

Research output: Journal article publicationJournal articleAcademic researchpeer-review

34 Citations (Scopus)

Abstract

A facile and scalable electrospinning method is employed to fabricate in situ N-doped, porous graphitic carbon nanofibers (CNFs) containing Si nanoparticles surrounded by nanocavities as durable high-rate Li-ion anodes. Nanocavities are created within the graphitic carbon spheres by electroless etching of the Si nanoparticles, which function not only as buffer to accommodate the volumetric expansion of Si upon lithiation but also as a conducting network for fast electron/ion transport. The Fe3C catalyst simultaneously formed within the fiber promotes the formation of highly graphitic carbon structures while the nitric acid etchant in situ generates functional CNFs with numerous mesopores and oxygenated functional groups, offering extra reaction sites for Li ions. With the ameliorating structural features acting synergistically, the resultant C-Si/F-CNF electrode delivers an exceptional initial reversible capacity of 1548 mA h g-1 at 0.1 A g-1, and remarkable high-rate capacities of 770 and 580 mA h g-1 at 2.0 and 5.0 A g-1 after 70 cycles with excellent capacity retention. This journal is
Original languageEnglish
Pages (from-to)17944-17951
Number of pages8
JournalJournal of Materials Chemistry A
Volume2
Issue number42
DOIs
Publication statusPublished - 14 Nov 2014
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)
  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)

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