Surface-Enhanced Raman Scattering (SERS) Spectroscopic Studies Of Several Nitrogen-Containing Organic Molecules On Roughened Au Electrode

In this paper we introduced briefly basical principle of Raman scattering spectroscopy, and characteristics, enhancement mechanisms and utilization of surface-enhanced Raman scattering (SERS) spectroscopy. SERS spectroscopy can provide information of adsorbed species at electrode surface under (sub)monolayer, and has become into a very strong tool for studying the processes of surface adsorption and surface reactions. Gold is an ordinary material for electrode and a good SERS substrate, and the study of nitrogen-containing organic molecules on this substrate is an interesting research subject. In this thesis, a new surface roughening method of gold electrode has been proposed with high SERS activity, and several nitrogen-containing organic molecules have been studied with SERS on this substrate.(1) We advanced a new roughening technique of gold surface utilizing disproportionation reaction under condition of setting constant anodic potential. Atomic force microscopic (AFM) image showed that the size of Au nanoparticles in the uniform deposit layer was within 200-400 nm, and thus this new tactic was a deeply roughening one. It was shown that by a probe molecule, pyridine, the SERS substrate obtained in this way could yield extremely intense SERS effect.(2) 1,10-phenanthroline (phen) adsorption and its surface complexes on roughened polycrystalline gold electrode were studied by SERS. The presence of Au-N adsorption band indicates that phen molecules are adsorbed on the Au surface via nitrogen atoms. And the occurrence of coordination bonds of Au-N and Au-X- (X: Cl, Br) together with the electrochemical measurements convincingly prove the formation of surface complexes l,10-phenAu2X6 or [1,10-phenAuX2]AuX4 during the...