Date of Award

4-2014

Degree Name

Doctor of Philosophy

Department

Chemistry

First Advisor

Dr. Sherine O. Obare

Second Advisor

Dr. Ekkehard Sinn

Third Advisor

Dr. Andre Venter

Fourth Advisor

Dr. Massood Atashbar

Keywords

Metal nanoparticles, synthesis, size dependent, electron transfer, semiconductor, fluorophores

Abstract

In recent years, nanoscale metallic particles have gained considerable interest due to their potential applications in advanced technology. Despite such interest, synthetic procedures that produce gram-scale, well-defined metallic nanoparticles with controlled size and shape, especially with diameters less than 5 nm remains a challenge. Our work has focused on developing synthetic procedures that produce well-defined platinum and palladium metal nanoparticles in the 1-5 nm size range. Thioether ligands were used as stabilizers and resulted in metal nanoparticles with controlled size. The nanoparticles were characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), selected area electron diffraction (SAED), x-ray photoelectron spectroscopy (XPS), electrochemistry and high-resolution transmission electron microscopy (HRTEM). Unique size-dependent electronic properties were found to arise when the particle diameter was less than 5 nm. We studied the changes in electronic properties of fluorophores and semiconductor nanoparticles brought in close proximity to the metal nanoparticles. The interaction of metal nanoparticles with the fluorophores was found to be size-dependent involving a surface energy transfer mechanism. Furthermore, the metal nanoparticles were found to store multiple electrons that were effective in the catalytic reduction of environmental pollutants.

Access Setting

Dissertation-Open Access

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