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Surface-enhanced Raman scattering (Surface-enhanced Raman Scattering, SERS) is a special kind of surface optical phenomena, high sensitivity, can greatly enhance the Raman scattering signal of adsorbed molecules, have been widely used in surface science and electrochemistry, metal corrosion, semiconductor optoelectronic devices, nanomaterials, biology, medicine, art, archeology and other related fields. Credits group metal of gold, silver, copper, etc.; alkali metal such as Li, Na; pure transition metals of Fe, Co, Ni, etc. or its alloy system; TiO2, and Fe2O3, of ZnO, Pb3O4 semiconductor such as rough surface can be observed SERS phenomenon. The contents and conclusions of the paper include the following aspects: 1, the use of sodium citrate as a reducing agent to improve the traditional method of preparation of silver sol different nano-silver sol. Zeta potential analyzer, transmission electron microscopy and UV-visible spectrophotometer, respectively, were observed stability of colloidal silver nanoparticles, size, shape, distribution and light absorption properties and crystal violet as a probe molecule to study the crystallization purple metallic silver particles in the surface of the substrate adsorption characteristics by Raman spectroscopy SERS activity of silver nanoparticles. The results show that: the amount of sodium citrate in the preparation process of colloidal silver particle size, morphology and SERS activity. 2, mainly by UV spectra and SERS spectra of different concentrations of HCl, HNO3, H2SO4, and their respective corresponding sodium and potassium salts added to the color of silver sol - Crystal Violet System, absorption spectra and SERS enhancement effect . 3, the paper is selected benzoic acid, methylene blue, 4 - mercaptopyridine, pyridine four molecules as SERS probe molecules, compare several different structures of molecules adsorbed on the surface of the silver colloid of SERS phenomenon and binding Gaussian Analysis calculated and reference literature on the the probe molecular vibration information more precise comparative analysis of conclusive evidence, and to estimate the pyridine probe molecules on the silver sol SERS enhancement. 4, different morphologies of ZnO substrate crystal violet molecule SERS enhancement semiconductor ZnO has been confirmed by the SERS enhancement, the enhancement factor of up to 102. By analyzing the UV spectra and SERS spectra have a preliminary understanding of mechanism of semiconductor enhanced chemical enhancement mechanism may play a major role on the SERS effect.
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