铑电极上的表面增强拉曼光谱研究(英文)

本文简要介绍了将铑电极用于表面增强拉曼光谱 (SERS)研究的方法 .具有较强活性的铑电极可以通过对电极施加方波电流进行恒电流粗糙获得 .对模型分子吡啶进行的表面拉曼光谱研究表明 ,该电极具有很好的稳定性和可逆性 ,并且其表面增强因子可达 4 0 0 0 .在对铑电极上一氧化碳的氧化过程进行的拉曼光谱研究中同时检测到桥式和线型吸附的C O和Pt C振动的拉曼信号 .本研究表明铑电极可作为多用的SERS基底 ,拉曼光谱可作为界面研究的通用工具 .

Rhodium as a Ubiquitous Substrate for Surface Enhanced Raman Spectroscopy

Raman Spectroscopy is a powerful technique in characterizing the molecular structure at the molecular level. However, only after the discovery of surface enhanced Raman scattering (SERS) effect, has it become one of the most widely used technique in surface sciences. The limitation that only Ag, Au and Cu can produce prominent SERS signal of practical significance, greatly hinders the application of this technique. Recently our group has made great progress in extending SERS to pure transition metal surfaces, such as Pt, Ni, Fe, Co etc［1］. Rh, due to its special application as catalysts in the catalytic or electrochemical reaction has made it one of the most important materials in surface sciences. It will be of great help for understanding the interfacial phenomenon and possibly the SERS mechanisms if we can extend SERS to the Rh surface. However, It has been found that, Rh is very difficult to be roughened since it will grow naturally in air an oxide layer which will retard the further formation of surface oxides. Furthermore, Rh is very easily oxidized to various forms of rhodium oxides as can be found from the phase diagram of Rh［2］. How to select a method to roughen the surface and to extend SERS to Rh seems not an easy task.