Flame Synthesis of Metal-Oxide/Carbide Nanowires

CBET-0755615Tse本研究的目标是探索和建立火焰合成条件与纳米线生长行为之间的关系。它将基于这样的假设，即对于给定的衬底材料，生长速度、晶体结构和纳米线的形态(如线和带)由局部气相温度、衬底温度和气相物种决定。在以前的工作中，PI开发了一种新的基于燃烧的技术，在大气条件下直接从微米级的金属颗粒快速合成单晶氧化物和碳化物纳米线。目前的研究将结合不同的火焰合成纳米线的经验表征和步骤，以实现对其形成的基本理解。使用逆流扩散火焰和插入的探针衬底将合成大量的金属氧化物/碳化物纳米线，其特征是基于激光的诊断。在过去的五年里，基于功能氧化物的一维纳米结构的研究因其在光学、光电子学、催化和压电学方面的独特和创新的应用而引起了人们的极大关注。半导体氧化物纳米线构成了一种特殊的一维纳米材料，它具有独特而均匀的几何形状，可控的晶体和表面结构，环境耐寒和稳定的表面，以及无位错的单晶体积。基于这些纳米结构，包括场效应管、超灵敏纳米气敏传感器、纳米谐振器和纳米悬臂在内的各种应用都成为可能。除了这些潜在的技术影响外，拟议工作的更广泛影响通过对研究生的教育以及将这项工作纳入纳米材料和高级诊断学课程而产生。这项工作还将进一步发展正在进行的行业合作伙伴关系，并将允许学生获得行业设施和合作机会。

CBET-0755615TseThe 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.