Deposition time dependence of the morphology and properties of tin-catalyzed silicon oxide nanowires synthesized by the gas-jet electron beam plasma chemical vapor deposition method

摘要

SiOx nanowires (SiOxNWs, x amp;= 2) were grown by gas-jet electron beam plasma chemical vapor deposition method according to the vapor-liquid-solid mechanism at different synthesis times (t(dep) = 0.5-5 min) using tin particles as a catalyst. Microropes of SiOxNWs were obtained at t(dep) of more than 1 min. The average growth rate of nanowires was about 19 nm/s. Fourier transform infrared (FTIR) spectroscopy shows that SiOxNWs synthesized at different t(dep) are very similar in chemical composition (x approximate to 2) and in the bonding network of SiOx. FTIR spectroscopy data on the chemical composition of nanowires are in good agreement with the results of X-ray energy dispersive spectroscopy (EDS) analysis. EDS mapping of silicon and oxygen indicates that the atoms are uniformly distributed in the nanowires. Also, FTIR measurements showed that a significant number of water-adsorbing silanol groups formed on the surface of the nanowires. Photoluminescence spectra of nanowires obtained at different t(dep) are typical of SiO2 and exhibit a broad band in the region 400-600 nm centered at similar to 475 nm. The contact angle for SiOxNWs is amp; 21 degrees and decreases to 4.4 degrees with increasing t(dep), indicating a superhydrophilic coating.