Date of Award
Andrea M. Goforth
Nanosilicon, Oxidation-reduction reaction, Photoluminescence
Silicon nanoparticles (Si NPs) have received much attention for their versatile applications in cell biology and medicine as in vivo molecular and cellular fluorescent markers. Recent studies have reported conversions of red-emitting silicon nanoparticles to blue-emitting particles. While blue emission is characteristic for 1-2 nm Si NPs, nanoparticles with larger radii that are closer to the Bohr exciton radius of bulk silicon (~ 4 nm) typically do not exhibit blue emission. Several studies have suggested that the oxidation of the surface of the silicon nanoparticles gives rise to the red-to-blue photoluminescence conversion. Herein, the oxidation and reduction potentials of 1-butanol, n-butylamine, and N,N-dimethylformamide (DMF) were measured and correlated to their ability to quench the photoluminescence of hydride-terminated Si NPs over time. The half-wave potentials of 1-butanol, n-butylamine, and DMF were measured to be 0.4416 V, 0.4979 V, and 0.7867 V. These half-wave potentials were studied on the basis that more electron-withdrawing solvents would result in a greater red-to-blue photoluminescence conversion and surface oxidation. Photoluminescence quenching studies showed that 1-butanol and DMF exhibited greater effects on the photophysical properties of the hydride-terminated Si NPs.
Lee, Eunice Y., "A Study on the Effects of Using Redox Active Solvents on the Photophysical Properties of Hydride-Terminated Silicon Nanoparticles" (2015). University Honors Theses. Paper 326.