The goal is this research is to explore and establish the relationship between flame-synthesis conditions and growth behavior of nanowires. It will work from the hypothesis that for a given substrate material, growth-rate, crystal structure, and nanowire morphologies such as wires vs. ribbons are determined by the local gas-phase temperature, substrate temperature, and gas-phase species. In previous work, the PI has developed a novel combustion-based technique to synthesize monocrystalline oxide and carbide nanowires directly from microsized metal grains at high rates under atmospheric conditions. The present research would combine empirical characterization of different flame-synthesized nanowires with steps to achieve fundamental understanding of their formation. A large number of metal oxide/carbide nanowires will be synthesized using using a counter-flow diffusion flame and an inserted probe substrate characterized laser-based diagnostics. Oxide and carbide synthesis will be investigated for the three base metals Al, Fe, and W. Over the past half-decade, research in functional oxide-based one-dimensional nanostructures has attracted considerable attention due to their unique and innovative applications in optics, optoelectronics, catalysis, and piezoelectricity. Semiconducting oxide nanowires constitute a special set of 1D nanomaterials that have a distinct and uniform geometrical shape, a controlled crystallographic and surface structure, environmentally hardy and stable surfaces, and a dislocation-free single-crystal volume. A variety of applications including field-effect transistors, ultra-sensitive nano-size gas sensors, nanoresonators, and nanocantilevers become realizable based on these nanostructures. Beyond these potential technological impacts, broader impacts of the proposed work arise through education of the graduate researchers and incorporation of this work into nanomaterials and advanced diagnostics courses. The work will also further ongoing industry partnerships and will allow students access to industry facilities and opportunities for collaboration.
