| Zinc, as a very important practical metal, has bee n extensively used in the scientific fields such as material science and power source. Num erous conventional electrochemical researches have been carried out on zinc, for example, studies of different behaviors of zinc in various electrolytes, corrosion and inhibition of zinc and the formation, structure and characteristic of the passivation film of zinc. Bu' all electrochemical techniques are excited and tested by electrical symbols, and they do not have the ability of identifying the molecules at the electrochemical interface. Therefore, it is imperative to develop spectroelectrochemical methods to better understand the electrochemical interface at molecular and atomic level.As one of the in-situ spectrum techniques in testing the species at electrochemical interface, surface enhanced Raman spectroscopy (SERS) has an advantage over otherspectroelectrochemical techniques such as IR by its high sensitivity, avoiding the interference of water and ease of attaining low frequency vibration which was related to interaction of adsorbates and metals. Many SERS stuciies were restricted to coinage metals, Ag, Au, Cu, which impeded the development of SERS to be a universal spectrometric measurement. In about 1980s, researches about SERS. on Cd and Hg make people assume that zinc metal is likely to have SERS effect, but till now there are no reports on SERS studies from bare Zn electrode. Due to the importance of zinc metal in application and basical research, this paper deals with the following research work in order to extend SERS to zinc system:1. Using a highly sensitive confocal microprobe Raman system, we systematically investigated various roughening procedures for Zn electrodes and successfully obtained the surface Raman spectra of pyridine on zinc for the first time. The double layer capacitance of the Zn electrode was measured and the surface roughness of Zn electrode was about 2. According to the formula based on the confocal microprobe Raman system and its definition, surface enhancement factor (G) of roughened Zn electrode wascalculated about 200 and the SERS effect of about 2 orders exists for zinc in our experiment and calculation.2. The adsorption behavior of probing molecule of pyridine and bipyridine at Zn electrode has been studied utilizing the SERS technique. The SERS spectra of pyridine had been systematically investigated with the change of the applied potential and supporting electrolytes. It was obvious that there were many differences between the SERS spectra of molecules adsorbed on Zn electrode ind other transition metals, which is attributed to its inherent electronic configuration. It is well known that the outer 3d and 4s orbits of zinc are filled with electrons and there is no empty d orbits to accept electrons, which is different from coinage and transition metals. Therefore, zinc is inclined to be an electron donor, which is not beneficial for it to interact with pyridine. Bipyridine had more strong interaction with zinc than pyridine, and there was a potential induced conformational transition for 2,2'-Bipy when it adsorbed on zinc.3. Based on the SERS active zinc substrate, we extended the SERS study to somesystems of practical importance on zinc .The inhibition mechanisms of imidazole andtbenzotriazole on zinc surfaces were investigated with the variations in potential and pH values.Imidazole absorbed on the zinc surface by its N atom and took a perpendicular position at any potential in neutral solution. In alkaline solution imidazole absorbed on the zinc surface by its N atom in a perpendicular position at positive potential, but as the potential moved negatively, the imidazole ring may change to be slightly inclined to the surface. Imidazole had more effective inhibition for zinc in neutral solution than in alkaline solution due to its more strong interaction wi h zinc.Benzotriazole (BTAH) interacted with zinc surface through its two N atoms of the triazole ring and surface complex polymer may...
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