A magnesiothermic route to multicomponent nanocomposites of FeSi 2@Si@graphene and FeSi2@Si with promising anode performance
- 주제(키워드) Nanocomposites , Nanoparticles , Graphene , Anode materialms , Lithium secondary batteries , Magnesiothermic reaction
- 등재 SCIE, SCOPUS
- 발행기관 Elsevier Ltd
- 발행년도 2014
- 총서유형 Journal
- URI http://www.dcollection.net/handler/ewha/000000097726
- 본문언어 영어
- Published As http://dx.doi.org/10.1016/j.electacta.2014.05.121
- 저작권 이화여자대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
The multicomponent nanocomposites of FeSi2@Si@graphene and FeSi2@Si are synthesized via the magnesiothermic reduction of core-shell Fe3O4@SiO2 nanoparticles with/without graphene oxide shell. In the course of the magnesiothermic reaction, the SiO2 and Fe3O4 components in the Fe3O4@SiO2 core-shell particles are transformed into elemental Si and FeSi2, respectively. The formation of intimately-coupled composite structure consisting of Si and FeSi2 domains as well as the coating of graphene layer is verified by high resolution-transmission electron microscopy. Both the nanocomposites of FeSi2@Si@graphene and FeSi2@Si show promising anode performance for lithium ion batteries, indicating a beneficial role of the electrochemically inactive FeSi2 domains in alleviating the drastic expansion/contraction of elemental Si during the electrochemical cycling. The better cyclability and rate characteristic are obtained for the FeSi2@Si@graphene nanocomposite than for the graphene-free FeSi2@Si one, which is attributable to the depression of pulverization and the enhancement of electrical conductivity upon the coating of graphene layer. The present work highlights that the magnesiothermic reaction provides a powerful synthetic route to multicomponent Si-based nanocomposites with tailored composition and complex geometry.
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