Application Of Ag Reduced With ZnO By Photocatalysis In SERS Substrate

Raman scattering is an optical phenomenon related to the molecular vibration and rotation, whose technologies has been widely applied in many fields of structural analysis for its many advantages. This paper taking theories and technologies of Raman spectra as the main content accomplish the following two works:Firstly, this article expound principles and technologies of Raman scattering systematically according to development of Raman spectroscopy, which range from discovery, development, explanation of basic principles to application of the Raman scattering, and to technologies of the Raman spectra. Then it also elaborate the basic theories of surface enhanced Raman scattering, technical characteristics, present situation and development of surface enhanced Raman scattering substrate, the advantages and disadvantages of the substrate and the characteristics of zinc oxide nanometer semiconductor and its application in technologies of surface enhanced Raman spectra.Secondly, we introduce a simple and novel method for synthesis of stable surface enhanced Raman scattering (SERS) substrates. Irregular silver nanostructures were deposited ZnO thin films in silver nitrate solution using ultraviolet radiation. ZnO thin films were prepared on the silicon wafer by sol-gel method. Then the nano structure was transformed into quasi-spherical silver particles by annealing as surface enhanced Raman scattering substrates. The efficiency of SERS substrates is evaluated from the relative SERS intensities of the adsorbate rhodamine6G (R6G) served as detected molecules. This novel SERS substrates demonstrated not only stronger Raman enhancement than traditional silver colloids but also excellent test stability in our experiment. Moreover, we found that a few spots possessed stronger enhancement activity than the more spots on SERS substrates, which is known as "hotspot". The article will discuss summarily the "hotspot" that is also frequently used to describe the place where SERS happens in the range of laser spot size.