Surface Enhanced Raman Spectroscopy of Halide Ions on Colloidal Silver: Morphology and Coverage Dependence
نویسندگان
چکیده
Transmission electron microscopy shows that the colloidal silver used as a substrate for surface enhanced Raman spectroscopy consists of 75-135 .~ average diameter faceted crystals, which can be made to aggregate in clusters of a few to thousands of particles. Aggregates are not required for observation of the SER spectrum of adsorbed halide ions or pyridine. Bromide is shown to adsorb more readily than chloride, and in time it displaces chloride on the silver surface. Spectra of halide ions adsorbed on sols with various particle morphologies lend additional support to our interacting dipole model describing the origins of the spectral band fine structure.
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Surface Enhanced Raman Spectroscopy of Halide Ions on Colloidal Silver: Simulation of Silver-halide Ion Spectra
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