| Transmission infrared spectroscopy has been used to study surface processes on porous silicon, SiO2, Al2O3, amorphous carbon, and single-walled carbon nanotubes inside of a vacuum cell.; The thermal oxidation of porous silicon by O2 was studied. Hydrogen removal near 523 K was found to initiate the oxidation reaction by uncapping Si-dangling bond sites capable of dissociative adsorption of O 2.; The cryogenic reaction between atomic hydrogen and trimethylgallium adsorbed on SiO2 was investigated. The atomic hydrogen was found to displace methyl groups from the trimethylgallium.; The adsorption and reaction of 2-chloroethylethyl sulfide (CEES) on thermally activated Al2O3 was studied. The C-Cl bond of CEES was found to react with isolated hydroxyl groups and Al3+O 2− Lewis acid-base pairs.; A new method for studying gas adsorption on opaque materials, such as amorphous carbon and carbon nanotubes, was devised by diluting the opaque material in a transparent material, such as KBr. Gases were found to diffuse into the sample and adsorb onto the opaque material's surface. This method was refined by preparing a thin layer of the opaque material on top of the transparent material, resulting in very little interaction between the two materials.; The amorphous carbon surface was found to contain aromatic and aliphatic hydrogen species, along with a small amount of oxygen species. The surface of this material reacted with ozone at room temperature to form a wide variety of carbonyl and ether species.; Chemically opened single-walled carbon nanotubes were found to contain carboxylic acid and quinone groups. These groups were removed upon heated to 1073 K, resulting in the formation of CO and CO2 gases.; Closed single-walled carbon nanotubes were found to react with ozone at room temperature, forming quinone and ether groups at defect sites, leaving the walls of the nanotube intact. These groups were removed by heating to 1073 K as CO and CO2 gas. (Abstract shortened by UMI.)... |
