title: Fluidized bed chemical vapor deposition of silicon on carbon nanotubes for Li-ion batteries.
abstract: Silicon was deposited on balls of entangled multi-walled carbon nanotubes (CNT) with a mean diameter of several hundreds of microns, by Fluidized Bed Chemical Vapor Deposition from silane (SiH4). The weight total percentage of deposited silicon was between 30 and 70%, to test their efficacy in Li-ion battery anodes. TEM and SEM imaging revealed that silicon deposits were of the form of nanoparticles uniformly dispersed on the whole CNT surface. The diameter of these nanoparticles increases with the deposited silicon percentage from 18 to 36 nm whereas their density remains constant at 5 10(22) nanoparticles/g of CNT. This indicates a low affinity of chemical species born from silane pyrolysis with the CNT surface for nucleation. The increase of the silicon nanoparticles diameter leads to the decrease of the specific surface area and the porous volume of the balls, probably due to the filling of the pores of the CNT network by silicon. A slight increase of the mean diameter of the balls was observed for the two highest silicon percentages, certainly due to the ability of the CNT network to be deformed under the mechanical stress induced by the silicon nanoparticles growth.
authors.affiliation: Laboratory of Chemical Engineering, University of Toulouse, ENSIACET/INP Toulouse/UMR CNRS 5503, 4, allée Emile Monso, BP84234, 31432 Toulouse, Cedex 4, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Coppey
authors.forename: Laure
authors.initials: L
authors.lastname: Noé
authors.forename: Marc
authors.initials: M
authors.lastname: Monthioux
authors.forename: Brigitte
authors.initials: B
authors.lastname: Caussat