CAREER: Aerosol Droplet Combustion Synthesis of Nonequilibrium Nanoscale Materials

职业：非平衡纳米材料的气溶胶液滴燃烧合成

• 批准号: 9733234
• 负责人: Joseph Helble
• 金额: $ 22万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9733234&HistoricalAwards=false
• 关键词: CAREER; Aerosol; Droplet; Combustion; Synthesis

Abstract - Helble This is a fundamental exploration of combustion aerosol synthesis to generate chemically complex nanoscale ceramic materials. In combustion aerosol synthesis, ceramic precursors are dissolved or dispersed in a combustible carrier; when this carrier is atomized into a high-temperature flame, each droplet can become a "microreactor" for nanoscale ceramic particle synthesis. The high temperature, exothermic droplet combustion reactions enable the generation of chemically complex, crystalline materials without need for further heat treatment. The first material to be examined is yttria-stabilized zirconia because of its applicability as a thermal barrier, coating, catalyst, and catalyst support. A range of yttria compositions is considered to determine whether the nanoscale material, with its high concentration of surface atoms, shows the same transitions in phase behavior as does conventional stabilized zirconia. Synthesis issues explored include the control of reacting aerosol droplet size, particle formation through the condensed-phase reaction and nucleation within the reacting droplet, and particle formation through the vaporization and subsequent condensation of ceramic compound vapors. Key issues are the ability to minimize agglomeration of nanoscale particles and the ability to control their chemical composition. Advanced ceramic materials consolidated from nanometer-scale ceramics have the potential to provide improved mechanical, optical, and electronic behavior over their larger-grained counterparts. Potential applications include barrier coatings, catalysts, structural materials, and cores of superconducting wires. Educational efforts include development of an aerosol science course using interactive learning and, in conjunction with the Boston Museum of Science, development of a hands-on interpretive module addressing the nanoscale world as a realm between atomic and macroscopic regimes.

摘要- Helble 这是一个基本的探索燃烧气溶胶合成产生化学复杂的纳米陶瓷材料。 在燃烧气溶胶合成中，陶瓷前体溶解或分散在可燃载体中;当这种载体雾化成高温火焰时，每个液滴都可以成为纳米陶瓷颗粒合成的“微反应器”。 高温、放热的液滴燃烧反应能够生成化学复杂的结晶材料，而无需进一步的热处理。 第一种要检查的材料是氧化钇稳定的氧化锆，因为它适用于作为热障，涂层，催化剂和催化剂载体。 氧化钇组合物的范围被认为是确定纳米级材料，其表面原子的高浓度，是否显示出相同的相行为的转变，作为常规的稳定氧化锆。 探讨的合成问题包括反应气溶胶液滴尺寸的控制，通过凝相反应和反应液滴内的成核的颗粒形成，以及通过陶瓷化合物蒸气的蒸发和随后的冷凝的颗粒形成。 关键问题是最大限度地减少纳米颗粒团聚的能力和控制其化学成分的能力。 由纳米级陶瓷固结而成的高级陶瓷材料具有比其大晶粒对应物提供改进的机械、光学和电子行为的潜力。 潜在的应用包括阻隔涂层、催化剂、结构材料和超导线芯。 教育工作包括利用互动学习开发气溶胶科学课程，并与波士顿科学博物馆合作开发一个实用的解释模块，将纳米级世界视为原子和宏观制度之间的领域。