| Gold island films, composed of gold nano-particles, hillocks, isolated or interconnecting islands, or holes, have potential applications in the fields such as chemical or biological sensing, surface-enhanced Raman scattering (SERS) and catalysis. As a result, the construction of gold island films has become an increasingly active field in material science and nanotechnology. Chapter 1 outlines a new method of making gold island films from gold thin films deposited on microscope glass slides, which has originated from a serendipitous observation of a gold film turning to pink. In this method, a gold film (5 nm--10 nm) is first deposited on a microscope glass slide via thermal evaporation. Then the gold-coated slide is heated at a relatively mild temperature (60°C--120°C) in nitrogen, or a vapor of water or iodobenzene for a various period of time. As a result, Gold island films with different morphologies form depending on original film thickness, temperature, heating time and vapor type. Environmental scanning electron microscopy (ESEM) and UV-vis spectroscopy have been applied to study the factors that have influence over morphologies formed, including film thickness, heating time, temperature and vapor type, and have been used to draw the connection between morphologies and optical properties.; We believe that capillary condensation plays a crucial role by creating capillary forces that draw the gold nanoparticles into intimate contact and accelerate the agglomerating process. Lin and Meier's model was used in this study to estimate the capillary force between gold nanoparticles within the films as a function of the relative humidity (RH) of the condensable vapor.; This new method may be applied to other substrates, other vapors and other metals, which will eventually expand the scope of its applications. The related preliminary results are not reported in this dissertation.; Chapter 2 summarizes the synthesis of methylsulfinyl-functionalized styrene monomers that were to be used to prepare highly cross-liked polystyrenes as a stationary phase for the purification and detection of saxitoxin and its derivatives. Chapter 3 summarizes the synthesis of oligothiophenes that were to be used to construct molecular electronic circuits. Chapter 4 summarizes the effort toward synthesizing methyl sorbitol. |
