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SERS active Ag-SiO₂ nanoparticles obtained by laser ablation of silver in colloidal silica.

ABSTRACT: Highly stable Ag-SiO₂ nanoparticle composites were first obtained by laser ablation of a silver target in an aqueous colloidal dispersion of silica and examined by UV-vis absorption spectroscopy, transmission electron microscopy and Raman spectroscopy. The surface enhanced Raman scattering (SERS) activity of these nanocomposites was tested using 2,2'-bipyridine as a molecular reporter and excitation in the visible and near-IR spectral regions. The computational DFT approach provided evidence of ligand adsorption on positively charged adatoms of the silver nanostructured surface, in a very similar way to the metal/molecule interaction occurring in the corresponding Ag(I) coordination compound.

SUBMITTER: Gellini C

PROVIDER: S-EPMC6142779 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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SERS active Ag-SiO2 nanoparticles obtained by laser ablation of silver in colloidal silica.

Gellini Cristina C Muniz-Miranda Francesco F Pedone Alfonso A Muniz-Miranda Maurizio M

Beilstein journal of nanotechnology 20180906

Highly stable Ag-SiO2 nanoparticle composites were first obtained by laser ablation of a silver target in an aqueous colloidal dispersion of silica and examined by UV-vis absorption spectroscopy, transmission electron microscopy and Raman spectroscopy. The surface enhanced Raman scattering (SERS) activity of these nanocomposites was tested using 2,2'-bipyridine as a molecular reporter and excitation in the visible and near-IR spectral regions. The computational DFT approach provided e ...[more]

PMID: 30254834

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