This dissertation is comprised with two main research projects: fabrication of thin films through an epoxide-catalyzed sol-gel process, and the dynamics of the photothermal initiation of Al/Fe2O3 metastable interstitial composite (MIC) materials.
The first is a discussion on the fabrication of thin films that was achieved with an epoxide-catalyzed sol-gel process and thermal processing. The Fe3+ oxide/hydroxide thin films on a quartz substrate, formed through the sol-gel process, were extremely uniform and homogenous with a film thickness of ~0.1µm. The Fe3+ gel thin films that were formed could be converted to !-Fe2O3 film, Fe or "-Fe2O3 films by calcination, which were characterized with UV-visible, XRD, AFM, and SEM. Also, Fe3+ gel thin film on a Si wafer was transformed into a multilayer structure, containing Fe2O3 and a Fe layer, at lower
temperatures then are required to initiate the combustion of bulk thermite. The reduced iron particles interfacially produced on silicon were confirmed by XPS and SEM. Finally, the photothermal initiation of Al (50 nm, 100 nm, and 3~4.5 µm) /Fe2O3 MIC materials with single 8 ns pulse of the 1064 nm of a Nd:YAG laser was studied with time-resolved spectroscopy in order to understand the dynamics occurring at early stages of the combustion.
As well, the effects of stoichiometry (the Al/Fe ratio) and compressed sample density on combustion dynamics were explained with the initiation time and the deflagration duration as the size of Al particle was changed from 50 nm to 120 nm. The initiation energy required to combust Al/Fe2O3 MIC was obtained by changing the power of the laser.
