title: Deposition of gold nanoparticles on silica spheres by electroless metal plating technique.
abstract: A previously proposed method for metal deposition with silver [Kobayashi et al., Chem. Mater. 13 (2001) 1630] was extended to uniform deposition of gold nanoparticles on submicrometer-sized silica spheres. The present method consisted of three steps: (1) the adsorption of Sn(2+) ions took place on surface of silica particles, (2) Ag(+) ions added were reduced and simultaneously adsorbed to the surface, while Sn(2+) was oxidized to Sn(4+), and (3) Au(+) ions added were reduced and deposited on the Ag surface. TEM observation, X-ray diffractometry, and UV-vis absorption spectroscopy revealed that gold metal nanoparticles with an average particle size of 13 nm and a crystal size of 5.1 nm were formed on the silica spheres with a size of 273 nm at an Au concentration of 0.77 M.
authors.affiliation: Department of Chemical Engineering, Graduate School of Engineering, Tohoku University, 6-6-07 Aoba, Aramaki-aza, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Yohei
authors.initials: Y
authors.lastname: Tadaki
authors.forename: Daisuke
authors.initials: D
authors.lastname: Nagao
authors.forename: Mikio
authors.initials: M
authors.lastname: Konno