用于电化学界面研究的共焦显微拉曼光谱技术(英文)

系统地介绍了将共焦显微拉曼光谱系统用于电化学界面研究的方法 ,包括铂电极的粗糙和电化学拉曼电解池的设计 .进行了铂上氢、氧和氯共吸附的拉曼光谱研究 .通过对甲醇氧化过程的现场跟踪 ,提出检测界面区溶液浓度变化和计算溶液 pH值的方法 .实验表明拉曼光谱技术可作为研究实际应用体系的重要工具 .

Confocal Microprobe Raman Spectroscopy for Investigating the Electrochemical Interface

The invention of the surface enhanced Raman spectroscopy (SERS) in the mid of 1970s, opened an entirely new and very promising area. However, it was found that SERS of practical application in electrochemistry can only be found on noble metal surfaces, such as Ag, Au and Cu that exhibit huge surface enhancement 1] . This greatly limits the application of SERS in electrochemistry. In electrocatalysis, corrosion inhibition, sensor, and power source, the most widely used materials are Pt, Fe and Ni and their alloys as well as Si. Thus, it is of great significance to extend surface Raman study to transition metals and semiconductors. Although the effort has been made along this direction by several groups since the late of 1970s, only recently, this goal has been attained 2,3] . The success of our work towards the goal is benefited from the improvement of the Raman instrumentation and the development of proper electrode surface pretreatment for transition metal surfaces. The employment of the charge_coupled device (CCD) detector, the confocal microscope, and the notch filter in the Raman instrumentation, brought up a new generation Raman instrument. It provides very high sensitivity that can partially break the limitation of the sensitivity to the surface Raman investigation 4] . The most important is, with the confocal pinhole, the instrument can only collect the light from the focus of the laser, thus it can effectively exclude the interference of the solution Raman signal, which makes the detection of very weak Raman signal from surface feasible. The emphasis of this paper is placed on the methodology. Some examples are given to demonstrate the advance in this area.