烯丙基硫脲与支持电解质阴离子在银电极上共吸附的拉曼光谱

Raman Spectroscopic Study on Coadsorption of 1Allyl2thiourea with Various Electrolyte Anions at Silver Electrodes

用表面增强拉曼散射光谱（ＳＥＲＳ）和时间分辨ＳＥＲＳ光谱（ＴＲＳＥＲＳ）等技术首次研究了烯丙基硫脲（ＡＴＵ）在ＨＣｌＯ４、Ｈ２ＳＯ４和ＨＮＯ３介质中与无机阴离子在银电极上的电化学共吸附行为．提出ＡＴＵ很可能以Ｓ端与银电极表面形成化学吸附键，仲氨基相对伯氨基距离表面较近，整个分子偏向烯丙基一侧倾斜吸附在表面上．ＣｌＯ－４、ＳＯ２－４和ＮＯ－３等弱吸附无机阴离子均能被ＡＴＵ诱导共吸附在其质子化了的仲氨基上，这３种无机阴离子被ＡＴＵ诱导共吸附的强弱顺序是ＣｌＯ－４＞ＳＯ２－４＞ＮＯ－３．被诱导共吸附的无机阴离子对ＡＴＵ在电极表面的化学吸附起到稳定剂的作用。

Using surface enhanced Raman scattering (SERS) and timeresolved surface enhanced Raman scattering (TRSERS) spectroscopies, the electrochemical coadsorption of 1allyl2thiourea(ATU) with one or two kinds of eletrolyte anions at sliver electrodes in perchloric acid, sulphuric acid, nitric acid medium respectively has been studied. The orientation of ATU on the surface was proposed. The results indicate that these anions can be coadsorbed on the electrode, induced by the protonated amino groups of ATU surface. The order of the coadsorption with ATU was found to be: ClO-4>SO2-4>NO-3.