Bi Nanoparticles Synthesis by a Bottom-up Wet Chemical Process

A process concerning bismuth nanoparticle synthesis by an eco-fiendly reductant in mixed solvents is proposed. The method relies upon a redox reaction carried out at mild operative conditions using tin salts as electron donors. The reaction is performed in the presence of polyvinyl-pyrrolidone (PVP) and sodium dodecyl-sulphate (SDS) as capping agents with the aim of investigating the role of such stabilizing compounds on particle average dimension and shape. The particles composition and diameter are determined by standard analytic techniques and by Dynamic Light Scattering. The precursor is dissolved in glycerol to hinder the formation of basic salts typically present in aqueous medium and to enhance the stability of the as-prepared zerovalent Bi nanoparticles. The slow-down of reaction kinetics related to the presence of glycerol is more than offset by its positive effect in terms of stability of the nanoparticles dispersion. From an applicative point of view, this study may help in identifying the best operating conditions for the production of zerovalent bismuth-based nanofluids by an energy-saving technology.