Ag|kCl|六氢吡啶体系表面增强喇曼散射效应的猝灭和恢复

在简述近年来电化学体系中表面增强喇曼散射(SERS)活性位置研究的实验结果和有关论述后, 着重报道作者在Ag/KCl/六氢吡啶体系中, Ag-Cl振动峰和六氢吡啶诸振动峰的强度, 在一定电位范围内电极被施加负脉冲电位后的同步下降, 以及采用氧化还原循环(ORC)处理得到同步恢复等新的实验结果, 并对上述体系中表面络合物的构成及其在SERS中的作用作了进一步的论证。

QUENCHING AND RESTORATION OF SURFACE-ENHANCED RAMAN SCATTERING FOR Ag/KCl/PIPERIDINE SYSTEM

The evidences for the existence of surface-enhanced Raman Scattering (SERS) active sites in electrochemical systems, both the experimental results and related discussion, have been briefly, reviewed. The irreversible decay (quenching effect) and restoration in SERS intensity of Ag/KCI/piperidine system has been studied by using negative potential pulse and using oxidation-reduction cycle (ORC) treatment applied to silver electrode, respectively, It is found that boehdegcee of both the irreversible intensity decay caused by the potential pulse and the intensity restoration caused by the ORC treatment are almost synchronous for all bands of SERS spectra. Besides, the data given by X-ray photo-electron spectra (XPS) shows that both chloride and piperidine molecules are present on surface of silver electrode which has been immersed in aqueous solution of KCl plus piperidine for several minutes. No detectable SERS signal has been found before ORC treatment. All these results can be interpreted in terms of the concept of surface complexes as SERS active sites existing on the surface of silver eletrode.