Electrochemically roughened rhodium electrode as a substrate for surface-enhanced Raman spectroscopy

A method to produce a substrate suitable for surface-enhanced Raman study on the pure massive Rh electrode was developed. The surface-enhanced Raman scattering (SERS) active Rh electrode with good stability, reversibility, and ease of preparation can be obtained by the control-current electrochemical roughening method. The surface enhancement factor was estimated to be 3 orders of magnitude. Such kind of enhancement allows the investigation of not only some molecules of large Raman cross-section (e.g., pyridine) but also other molecules of very small Raman cross-section (like CO). This result shows that the Rh surface can be used as a useful substrate for the combined electrochemical and Raman study of some systems that are both of fundamental and application interest.