title: Characterization of Ag/Pt core-shell nanoparticles by UV-vis absorption, resonance light-scattering techniques.
abstract: The water-soluble Ag/Pt core-shell nanoparticles were prepared by deposition Pt over Ag colloidal seeds with the seed-growth method using K2PtCl4 with trisodium citrate as reduced agent. The Ag:Pt ratio is varied from 9:1 to 1:3 for synthesizing Pt shell layer of different thickness. A remarkable shift and broadening of Ag surface plasmon band around 410 nm was observed. The contrast of TEM images of Ag/Pt colloids has been obtained. Various techniques, such as transmission electron microscopy (TEM), UV-vis absorption and resonance light-scattering spectroscopy were used to characterize nanoparticles. The data of TEM, UV-vis and resonance light-scattering spectrum all confirm formation of Ag/Pt core-shell nanoparticles. Resonance light-scattering and emission spectrum show the Ag and Ag/Pt core-shell nanoparticles have a nonlinear light-scattering characteristic.
authors.affiliation: Department of Chemistry, Nankai University, Tianjin, China. lxchen@nankai.edu.cn
authors.forename: Langxing
authors.initials: L
authors.lastname: Chen
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Zhao
authors.forename: Yufen
authors.initials: Y
authors.lastname: Jiao
authors.forename: Xiwen
authors.initials: X
authors.lastname: He
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Yukui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D008027:Light; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D010984:Platinum / Q000737:chemistry*; D012542:Scattering, Radiation; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D012834:Silver; D010984:Platinum