Ultrasonic assisted polyol-reduction of HAuCl4 for nanoparticle decoration of multiwall carbon nanotubes

Abstract

The decoration of carbon nanotubes with metallic nanoparticles has been extensively studied for different systems. Despite the fact that several routes are available for the production of these heterostructures, their complexity and large amount of different reagents severely hinder their applicability. In this study, we propose an alternative route based on an ultrasonic assisted polyol reduction, which requires lower temperatures and amount of reagents when compared to traditional methodologies. Furthermore, the used solvent (ethylene glycol) is more environmentally friendly than other common reagents, resulting in a less aggressive process. Weobserved that the proposed route provides the possibility of straightforwardly tune the final nanoparticle size by controlling simple parameters such as exposure time and relative reagent concentrations. Moreover, the influence of the bath temperature has been studied, finding an upper limit of 50 °Cfor the proposed methodology.