Synthesis of micro sphere-like bismuth nanoparticles by microwave assisted polyol method; designing a novel electrochemical nanosensor for ultra-trace measurement of Pb2+ ions

Abstract

In the present work, Bi nanostructures were successfully synthesized with the aid of Bi(NO₃)₃·5H₂O as the starting reagent in the presence of propylene glycol as the solvent and surfactant through the very fast and convenient microwave-assisted polyol method. In addition, the effects of preparation parameters such as irradiation time, pH and solvent on the reaction time, morphology and particle size of Bi nanostructure were studied by SEM images. It was found that the reaction time, size and morphology of the products could be greatly influenced by the aforementioned parameters. To the best of our knowledge, this is the first report on the synthesis of Bi nanostructures with different morphologies by microwave-assisted polyol process. The as-synthesized products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) and spectra energy dispersive analysis of X-ray (EDS). Finally, as an application, the synthesized Bi NSs with purified MWCNT were applied for the modification of a pencil graphite electrode for an ultra-trace sensing of Pb²⁺ ions. In this way, by the use of Bi-NPs/puMWCNT/PGE, the limit of detection for Pb²⁺ was found to be 1.7 nmol L⁻¹.