Electro co-deposition of copper-silver nanocrystallite alloy cluster: A way for tunable SERS substrate development

Abstract

Surface-enhanced Raman spectroscopy (SERS) exhibits intriguing analytical application owing to their non-invasive method, specificity, and sensitivity. However, development of tunable SERS active substrate remains a challenge. Herein, we report a straightforward chronoamperometric co-deposition strategy, utilizing a reducing agent, to form bimetallic coating comprised of Cu/Ag on silica substrate, where alteration of deposition current endows fractional variations in the nucleation/growth of Cu2+ → Cu+/Cu0 and Ag2+ → Ag+/Ag0. Properties of optical reflectance, surface chemistry, topography, and nanocrystallite cluster orientation were characterized. Experimental results confirm bimetallic coating with large proportion of Ag on Cu matrix could enable better SERS behavior with studied model, Rhodamine 6G.

Keywords

• One-pot electrodeposition
• Nanocrystalline materials
• Optical material and properties
• SERS