Using laser ablation in liquid (LASIS) method to synthesize silver nanoparticles for SERS applications

Abstract

In this work, colloid formation with laser ablation in distilled water was used to investigate the influence of ablation time and pulse repetition frequency in generating silver nanofluids. The nature (size and shape) of the nanoparticles were investigated using transmission electron microscopy (TEM) while the elemental composition of the generated nanoparticles was explored using energy-dispersive X-ray fluorescence (EDXRF). The EDXRF spectra confirmed the presence of silver as the dominant element in the nanofluid. TEM showed that the size of the generated nanoparticles varies with the concentration of silver based on the change in Laser ablation time (LAT) and the pulse repetition frequency (PRF). The localized surface plasmon resonance band of silver in the fluid was explored using UV–VIS with the absorption band observed at around 408 nm. The generated nanofluid was then used as a substrate in surface enhanced Raman spectroscopy (SERS). The conclusion drawn from this work is that the laser ablation time and pulse repetition rate can be modified to produce reproducible silver nanofluids for subsequent SERS applications.