Microwave Synthesis of Colloidal Germanium Nanoparticles

Group IV elements, such as silicon and germanium, have been of much of interest due to their semi-conducting properties on the nanoscale. On the nanoscale, quantum confinement effects result in changes in electronic and optic properties than can be tuned through altering synthesis methods. Germanium nanoparticles (Ge NPs) have been investigated for their potential use in a wide variety of areas including for energy conversion, biological imaging, and in optoelectronics. Ge NPs experience quantum confinement when synthesized to < 24 nm in diameter, allowing quantum confinement effects to be seen at relatively large NP size and tuned through changes in NP size. The surface ligand of NPs as well as the NP shape are other ways in which electronic properties of semi-conducting NPs can be altered. The goal of this research is to synthesize and characterize the properties of Ge NPs with varying sizes, surface ligands, and shape.This thesis presents synthesis methods and the characterization of Ge NPs with varying surface ligands and of Ge NPs synthesized using a known shape-directing agent. The results of these experiments are described in two chapters: (1) Extinction Coefficient of Germanium Nanoparticles, (2) Shape Control of Germanium Nanoparticles with Polyvinylpyrrolidone