Synthesis and Characterisation of a Graphene Oxide-Gold Nanohybrid for Use as Test Material
Taiwo Hassan Akere, Aline Maria Zigiotto de Medeiros, Diego Stéfani T. Martinez, Bashiru Ibrahim, Hanene Ali‐Boucetta, Eugenia Valsami‐Jones
Abstract
This paper reports the synthesis and characterization of a graphene oxide-gold nanohybrid (GO-Au) and evaluates its suitability as a test material, e.g., in nano(eco)toxicological studies. In this study, we synthesised graphene oxide (GO) and used it as a substrate for the growth of nano-Au decorations, via the chemical reduction of gold (III) using sodium citrate. The GO-Au nanohybrid synthesis was successful, producing AuNPs (~17.09 ± 4.6 nm) that were homogenously distributed on the GO sheets. They exhibited reproducible characteristics when characterised using UV-Vis, TGA, TEM, FTIR, AFM, XPS and Raman spectroscopy. The nanohybrid also showed good stability in different environmental media and its physicochemical characteristics did not deteriorate over a period of months. The amount of Au in each of the GO-Au nanohybrid samples was highly comparable, suggesting a potential for use as chemical label. The outcome of this research represents a crucial step forward in the development of a standard protocol for the synthesis of GO-Au nanohybrids. It also paves the way towards a better understanding of the nanotoxicity of GO-Au nanohybrid in biological and environmental systems.