Prof. Deon Miles presented his recent research at Tuskegee University on March 30, 2016. His talk was titled “Made to Measure: Synthesis and Characterization of Water-Soluble Monolayer-Protected Quantum Dots”. The abstract of his seminar is shown below:
Water-soluble, monolayer-protected quantum dots (QDs) were synthesized using several water-soluble thiols and alternative metal salts (e.g., cadmium acetate, zinc sulfate). QDs were synthesized at temperatures as low as -55 °C in attempts to control the growth of the nanoparticles. The optical properties of QD solutions were characterized using UV-visible and fluorescence spectroscopies. The hydrodynamic radius of the QDs was determined using pulsed field gradient (PFG) NMR. The diffusion coefficient of the nanoparticles, in concert with a small reference molecule, was determined using PFG-NMR. For reference, the diffusion coefficient of a redox-active molecule was calculated using cyclic voltammetry. Subsequently, the size of the nanoparticles was calculated using a modified version of the Stokes-Einstein equation. Size-exclusion chromatography (SEC) was employed in attempts to purify and separate the QDs by size. Also, the solubility and spectral properties of the QDs in different solvents (i.e., water, methanol, and ethanol) was studied.