Production of SERS Substrates Using Ablated Copper Surfaces and Gold/Silver Nanoparticles Prepared by Laser Ablation in Liquids

Abstract

Our study aimed to produce SERS substrates using nanostructured copper (Cu) surfaces prepared by laser ablation in water. A laser ablation schema was designed for this purpose. The laser power and laser irradiation time for creating a nanostructured surface suitable for SERS were determined. To increase the enhancement factor (EF) of the SERS substrates, gold (Au) and silver (Ag) nanoparticles were deposited on the ablated Cu surfaces to produce AuNP/aCu and AgNP/aCu substrates. The Au (and Ag) nanoparticles were also prepared by laser ablation of a Au (and Ag) piece in ethanol. The EFs for SERS of the AuNP/aCu and AgNP/aCu substrates are 1.2 × 106 and 6 × 106, respectively. The SERS spectra of malachite green with low concentrations of 0.1 ppm can be detected with high quality by using these SERS substrates.