Electrochemical Synthesis of Flower-Like Gold Nanoparticles for SERS Application

Surface-enhanced Raman spectroscopy (SERS) is a technique that is increasingly used in the identification and quantification of organic molecules at very low concentrations. In this analytical technique SERS-active substrates play a crucial role. Beside silver, gold is also widely used as a material for making SERS substrates. In this report we present a simple method for synthesizing arrays of flower-like gold nanoparticles (also referred to as gold nanoflowers—AuNFs), which can be used as SERS substrates. The AuNFs have been electrodeposited on a silicon surface coated with silver nanoparticles, which served as seeds for the growth of AuNFs. As a result, AuNFs were formed on the silicon surface with relatively dense density and with fairly uniform distribution. Arrays of AuNFs, as SERS substrates, were tested with a rhodamine B (RhB) molecular probe. The results showed that these AuNFs allow the detection of RhB down to a concentration of 1 ppb, a relatively low concentration. This demonstrates the applicability of fabricated AuNFs as a highly active SERS substrate.