Continuous Production of Semiconductor and Hybrid Nanocrystals by Spray Pyrolysis

通过喷雾热解连续生产半导体和混合纳米晶体

• 批准号: 0652042
• 负责人: Mark Swihart
• 金额: $ 28.01万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-15 至 2010-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0652042&HistoricalAwards=false
• 关键词: Continuous; Production; Semiconductor; Hybrid; Nanocrystals

PI: Mark Swihart Institution: SUNY Buffalo Proposal Number: 0652042Title: GOALI: Continuous Production of Semiconductor and Hybrid Nanocrystals by Spray PyrolysisThe PI plans to investigate the possibilities and limitations of spray pyrolysis methods for producing semiconductor and multicomponent nanocrystals of sufficiently small size to exhibit size- and shape-dependent optical and electronic properties. A vast array of potential applications based on these size and shape-tunable properties may be possible, ranging from biological imaging to solar cells and light-emitting diodes. Development of reproducible, controllable, and scalable continuous processes for producing these materials is essential to the realization of these applications. In spray pyrolysis, variants of which will be developed and explored here, a liquid precursor solution is sprayed as a mist of fine droplets (an aerosol) that is heated to induce formation of solid particles. He will study two spray pyrolysis approaches: (1) complete evaporation/vapor phase nucleation mode in which the aerosol serves as a means of delivering high concentrations of moderate volatility precursors into the gas phase, and (2) incomplete evaporation mode with formation of multiple product particles per precursor droplet, in which each aerosol droplet serves as a femtoliter-scale liquid phase reactor that, by virtue of its small size, can be heated or cooled very rapidly and remains uniform in concentration and temperature. The first approach expands on the capabilities of other vapor-phase synthesis approaches by allowing use of lower-volatility and lower-stability precursors than would otherwise be possible. The second approach allows one to extend powerful solution-phase methods to higher temperatures and shorter reaction times than are practical in conventional batch processes in solution.Intellectual Merit: The PI's recent advances in solution phase synthesis of anisotropic and hybrid semiconductor nanocrystals and in spray pyrolysis synthesis of other materials, suggest natural research directions for combining and extending these approaches. This will advance both nanoparticle synthesis capabilities and our understanding of the kinetics of nanocrystal nucleation, growth, and shape evolution. The project goals are to:(1) Establish the extent to which solution-phase methods of producing semiconductor nanocrystals and hybrid nanocrystals can be applied in the vapor-phase via complete evaporation and gas phase reaction of precursors delivered as an aerosol.(2) Demonstrate continuous production of high quality spherical, anisotropic, and hybrid semiconductor nanocrystals within aerosol droplets at higher temperature and shorter reaction times than are feasible in batch solution phase syntheses.(3) Apply principles and tools of chemical reaction engineering to the spray pyrolysis process to investigate the kinetics of nanocrystal nucleation and growth, and to design improved spray pyrolysis processes that produce higher quality nanocrystals.Broader Impact: The proposed work will lead to development of new, continuous, relatively high-throughput processes for the production of semiconductor nanocrystals, particularly anisotropic and hybrid nanocrystals. This will have technological impact by expanding the range of applications for which such semiconductor nanocrystals can be considered. Through this work, two Ph.D. students will be trained in the aerosol synthesis of nanoscale materials and develop cross-disciplinary skills in chemistry, materials science, and chemical engineering. Undergraduates will participate in this project through the NSF REU program, and through additional targeted programs such as the McNair Scholars program and the Louis Stokes Alliance for Minority Participation (LS-AMP) program. The PI's group has had increasing success in recruiting minority participants, and this project will build on this success and expand it with outreach to middle and high-school students and teachers.

PI: Mark Swihart机构：纽约州立大学布法罗分校提案编号：0652042标题：目标ali：通过喷雾热解法连续生产半导体和混合纳米晶体PI计划研究喷雾热解法生产半导体和多组分纳米晶体的可能性和局限性，这些纳米晶体的尺寸足够小，能够表现出与尺寸和形状相关的光学和电子特性。从生物成像到太阳能电池和发光二极管，基于这些尺寸和形状可调特性的大量潜在应用可能成为可能。开发可重复的、可控的、可扩展的生产这些材料的连续过程对于实现这些应用至关重要。在喷雾热解（这里将开发和探索其变体）中，液体前体溶液被喷射成细液滴的雾状（气溶胶），加热以诱导形成固体颗粒。他将研究两种喷雾热解方法：(1)完全蒸发/气相成核模式，气溶胶作为一种将高浓度的中等挥发性前驱体输送到气相的手段；(2)不完全蒸发模式，每个前驱体液滴形成多个产物颗粒，每个气溶胶液滴作为一个飞升级的液相反应器，由于其体积小，可以非常迅速地加热或冷却，并保持浓度和温度均匀。第一种方法扩展了其他气相合成方法的能力，允许使用比其他方法更低挥发性和更低稳定性的前体。第二种方法允许人们将强大的溶液相方法扩展到更高的温度和更短的反应时间，而不是在传统的溶液批处理过程中。智力优势：PI在各向异性和杂化半导体纳米晶体的固相合成以及其他材料的喷雾热解合成方面的最新进展，为这些方法的结合和扩展提供了自然的研究方向。这将提高纳米粒子的合成能力和我们对纳米晶体成核、生长和形状演变动力学的理解。该项目的目标是：(1)通过将前驱体作为气溶胶进行完全蒸发和气相反应，确定生产半导体纳米晶体和混合纳米晶体的溶液相方法在多大程度上可以应用于气相。(2)证明在气溶胶液滴内以更高的温度和更短的反应时间连续生产高质量的球形、各向异性和混合半导体纳米晶体比批量液相合成可行。(3)将化学反应工程的原理和工具应用到喷雾热解过程中，研究纳米晶体成核和生长的动力学，设计改进的喷雾热解工艺，生产出更高质量的纳米晶体。更广泛的影响：提出的工作将导致新的、连续的、相对高通量的半导体纳米晶体生产工艺的发展，特别是各向异性和混合纳米晶体。这将通过扩大半导体纳米晶体可以考虑的应用范围而产生技术影响。通过这项工作，两名博士生将在纳米材料的气溶胶合成方面得到培训，并在化学、材料科学和化学工程方面发展跨学科技能。本科生将通过NSF REU项目，以及其他有针对性的项目，如麦克奈尔学者项目和路易斯·斯托克斯少数民族参与联盟（LS-AMP）项目参与该项目。该项目小组在招募少数族裔参与者方面取得了越来越大的成功，该项目将在这一成功的基础上，将其扩展到初高中学生和教师。