This work was supported by the Burroughs Wellcome Fund (Award Number 1007294.01, A.M.G.), and the Oregon Nanoscience and Microtechnologies Institute (A.M.G) and via start-up funds from Portland State University (A.M.G.). We also acknowledge the National Science Foundation for XRD instrumentation (NSF-MRI, Award Number DMR- 0923572).
Metal clusters, Bismuth, Nanoparticles -- Synthesis, Oxidation-reduction reaction, Colloids -- Technological innovations
Herein, we report an aerobic synthesis method to produce bismuth nanoparticles (Bi NPs) with average diameters in the range 40-80 nm using commercially available bismuth triiodide (BiI3) as starting material; the method uses only readily available chemicals and conventional laboratory equipment. Furthermore, size data from replicates of the synthesis under standard reaction conditions indicate that this method is highly reproducible in achieving Bi NP populations with low standard deviations in the mean diameters. We also investigated the mechanism of the reaction, which we determined results from the reduction of a soluble alkylammonium iodobismuthate precursor species formed in situ. Under appropriate concentration conditions of iodobismuthate anion, we demonstrate that burst nucleation of Bi NPs results from reduction of Bi3+ by the coordinated, redox non-innocent iodide ligands when a threshold temperature is exceeded. Finally, we demonstrate phase transfer and silica coating of the Bi NPs, which results in stable aqueous colloids with retention of size, morphology, and colloidal stability. The resultant, high atomic number, hydrophilic Bi NPs prepared using this synthesis method have potential for application in emerging X-ray contrast and X-ray therapeutic applications.
Locate the Document
Hayden Winter et al 2018 Nanotechnology in press.