Making a Surface-Enhanced Raman Scattering-Active Pt Ultramicroelectrode by Electrochemically Adsorbing Au-core@Pt-shell Nanoparticles

Creating surface-enhanced Raman scattering (SERS) activity on an electrode is key to performing in situ electrochemical SERS measurements. Electrochemical adsorption of SERS-active nanoparticles onto an electrode was a clean method. The electrochemical adsorption of SERS-active Au-core@Pt-shell (Au@Pt) nanoparticles on a Pt ultramicroelectrode has not been explored yet. Here, we demonstrate a method of making a SERS-active Pt ultramicroelectrode by electrochemically adsorbing Au@Pt nanoparticles. The applied voltage and adsorption time were key parameters for improving the sensitivity of the SERS measurement on a Pt ultramicroelectrode, which were optimized according to the SERS intensity of p-methylthiophenol. Our methods were available on Pt ultramicroelectrodes with different radii. The potential-dependent SERS of p-methylthiophenol showed that the prepared Pt ultramicroelectrode covered by Au@Pt nanoparticles can be used in EC-SERS measurements.