Synthesis of Monodisperse Superconducting Lead Nanocrystals

We report on a new organic-phase synthesis method to produce a large quantity of high-quality monodisperse population of superconducting lead (Pb) nanocrystals. They are obtained from the alcohol reduction of a mixture of lead oleate and lead acetate in the presence of trioctylphosphine in octadecene. We show that the details of lead carboxylate mixture preparation is the key parameter in controlling the nucleation rate of the synthesis. Because mixtures of metal carboxylate have been widely used in synthesizing various high-quality metals or metal-oxide nanocrystals, the results herein should contribute to the understanding of the detailed mechanisms of these syntheses. Because of the large quantities provided by this synthesis, these nanocrystals are particularly well adapted for studies of the effect of quantum confinement on superconductivity.