title: Instantaneous formation of SiOxnanocomposite for high capacity lithium ion batteries by enhanced disproportionation reaction during plasma spray physical vapor deposition.
abstract: Nanocomposite SiOxparticles have been produced by a single step plasma spray physical vapor deposition (PS-PVD) through rapid condensation of SiO vapors and the subsequent disproportionation reaction. Core-shell nanoparticles, in which 15 nm crystalline Si is embedded within the amorphous SiOxmatrix, form under typical PS-PVD conditions, while 10 nm amorphous particles are formed when processed with an increased degree of non-equilibrium effect. Addition of CH4promotes reduction in the oxygen contentxof SiOx, and thereby increases the Si volume in a nanocomposite particle. As a result, core-shell nanoparticles withx= 0.46 as anode exhibit increased initial efficiency and the capacity of lithium ion batteries while maintaining cyclability. Furthermore, it is revealed that the disproportionation reaction of SiO is promoted in nanosized particles attaining increased Si diffusivity by two orders of magnitude compared to that in bulk, which facilitates instantaneous composite nanoparticle formation during PS-PVD.
authors.affiliation: Department of Materials Engineering, The University of Tokyo , Hongo , Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Tashiro
authors.affiliation: Shimane Institute for Industrial Technology , Matsue , Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Dougakiuchi
authors.affiliation: Department of Materials Engineering, The University of Tokyo , Hongo , Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kambara
keywords: 103 Composites; 206 Energy conversion / transport / storage / recovery; 305 Plasma / Laser processing; 50 Energy materials; Lithium ion batteries; disproportionation reaction; plasma spray; silicon monoxide nanoparticle