In-situ preparation and properties of gold nanoparticles embedded polypyrrole composite

Abstract

A composite was formed by polypyrrole (Ppy), gold nanoparticles (AuNPs) and multi-walled carbon nanotubes (MWCNT) using chloroauric acid (HAuCl4). MWCNT were carboxy functionalized by oxidation resulting into oxidized MWCNT (OMWCNT). The composite was characterized spectroscopically, structurally and morphologically by Fourier transform infrared (FT-IR) spectroscopy, Ultraviolet-visible (UV-Vis) spectroscopy, X-ray photoelectron spectrocopy (XPS), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and High-resolution transmission electron microscopy (HRTEM) studies which revealed about its successful formation. UV-Vis spectroscopy suggested the in-situ formation of AuNPs, their dispersion into the composite and presence of OMWCNT. XPS analysis revealed the existence of Au, C, N and O elements, signifying the desired formation of the composite. Morphological studies depicted the wrapping of OMWCNT by Ppy along with the presence of dispersed AuNPs. Its electrochemical examination suggested good electron transfer ability of AuNPs and OMWCNT. The interaction of composite with Cd2+ ions was investigated both optically and electrochemically, making it a potential candidate for Cd2+ sensing. Furthermore, its catalytic activity was also shown, by reduction of methylene blue dye.