Attenuation of surface‐enhanced Raman spectroscopy response in gold–platinum core‐shell nanoparticles

Abstract

Abstract Colloidal gold particles (11.2 nm) were coated with platinum overlayers, resulting in bimetallic particles with 1–8 mol% Pt. These particles were characterized using electron microscopy, energy‐dispersive x‐ray spectroscopy and electrochemistry confirming the Au–Pt core‐shell structure. The UV–visible spectra showed only minimal red shifts with increasing Pt content. The Raman spectra, on the other hand, changed dramatically with slight increases in Pt, resulting in a loss of appreciable surface‐enhancement effects by 4 mol% Pt. Copyright © 2002 John Wiley & Sons, Ltd.