Charging and Heating Dynamics of Nanoparticles in Nonthermal Plasmas

非热等离子体中纳米颗粒的充电和加热动力学

• 批准号: 0903842
• 负责人: Uwe Kortshagen
• 金额: $ 10万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0903842&HistoricalAwards=false
• 关键词: Charging; Heating; Dynamics; Nanoparticles; Nonthermal

Proposal Title: Charging and Heating Dynamics of Nanoparticles in Nonthermal PlasmasPrincipal Investigator: Kortshagen, Uwe R. Institution: University of Minnesota-Twin Cities Proposal No: CBET-0903842 Various aspects of "dusty" or "complex" plasmas have continued to excite the plasma com-munity since the 1980s. The first wave of interest was sparked by the detrimental effects of the formation of nanoparticles during the manufacture of microelectronic devices. In parallel, the discovery of exciting new physical phenomena in strongly coupled plasmas gave birth to the booming field of complex plasma studies. Recently a new focus of attention has emerged: Using reactive dusty plasmas as controllable sources of nanoparticles. These nanoparticles have interesting physical and chemical properties that make them promising for novel applications. However, even after more than a decade of study, some of the most basic physical processes of such "nanodusty" plasmas are still poorly understood. Moreover, due to the difficulties of preparing well-characterized experimental systems of "nanodusty" plasmas, most of our knowledge is based on models that lack experimental verification.The overall objective of this research is to study the fundamental dynamics of nanoparticle charging and heating in highly defined, well-characterized low temperature plasma environments. To achieve this objective, a unique process to synthesize highly monodisperse, luminescent nanocrystals with well-defined diameters in the range of 3-20 nm will be used; these particles will be injected into carefully designed and characterized test plasmas. For the nanoparticle charging problem, experiments will be performed with size-controlled nanoparticles to test whether the orbital-motion-limited theory or a theory accounting for collisional effects needs to be used for small nanoparticles. Another high-risk/high-reward experiment will attempt to measure, for the first time, the charge distribution of nanoparticles immersed in a plasma. Results of these experiments will provide new information for accompanying modeling studies. For nanoparticle heating in plasmas, a set of first-ever experiments will be performed using "nanoparticle thermometers" to study the average temperature of monodisperse nanoparticles in plasmas as well as to gain information about their temperature distribution function. One set of experiments will exploit the temperature-dependence of the photoluminescence of nanoparticles to gain information about particle temperatures. Another set of experiments will use the nanoparticles' microstructure to determine whether the particle temperature reached or exceeded the particles? crystallization temperature. Results of these experiments will be compared to numerical models for particle heating.This research has a wide range of broader impacts. On the technical side, it will build the scientific foundation for the use of plasmas as sources of functional nanoparticles for uses in nanotechnology. It will also serve as a springboard for a number of education and outreach activities. These include K-12 outreach through local public school districts; involvement of undergraduates in research; training of graduate and undergraduate students in a highly interdisciplinary research environment; teaching of new interdisciplinary graduate courses; fostering greater involvement of women and underrepresented groups in our graduate research programs; and active engagement with industry.

提案标题：非热等离子体的纳米颗粒的充电和加热动态研究员：Kortshagen，Uwe R. Institution：明尼苏达大学-Twin城市提案号：CBET-0903842：CBET-0903842“尘土”或“复杂”等离子体的各个方面继续激发了以下1980年代的质量community。在微电器设备制造过程中，纳米颗粒形成的有害影响引起了第一波的兴趣。同时，在强耦合等离子体中发现令人兴奋的新物理现象的发现诞生了复杂的等离子体研究的蓬勃发展领域。最近出现了新的注意力：使用反应性灰尘等离子体作为可控纳米颗粒的来源。这些纳米颗粒具有有趣的物理和化学特性，使它们有望成为新颖的应用。但是，即使经过十多年的研究，这种“纳米固定”等离子体的一些最基本的物理过程仍然知之甚少。此外，由于难以准备“纳米固定”等离子体的特征化实验系统，我们的大多数知识是基于缺乏实验验证的模型。这项研究的总体目的是研究纳米颗粒充电和加热的基本动力学，在高度定义的，良好的，含有良好的低温低温血浆环境中。为了实现这一目标，将使用一个独特的合成高度单分散的过程，将使用定义明确的直径范围为3-20 nm的发光纳米晶体；这些颗粒将被注入精心设计和表征的测试等离子体中。对于纳米颗粒充电问题，将使用大小控制的纳米颗粒进行实验，以测试是否需要用于小纳米颗粒的轨道 - 运动限制理论或理论涉及碰撞效应的理论。另一个高风险/高回报实验将首次尝试测量浸入血浆中的纳米颗粒的电荷分布。这些实验的结果将为随附的建模研究提供新的信息。 对于等离子体中的纳米颗粒加热，将使用“纳米颗粒温度计”进行一组首次实验，以研究等离子体中单分散纳米颗粒的平均温度，并获得有关其温度分布功能的信息。一组实验将利用纳米颗粒的光致发光的温度依赖性，以获取有关颗粒温度的信息。另一组实验将使用纳米颗粒的微结构来确定颗粒温度是否达到或超过颗粒？结晶温度。这些实验的结果将与用于颗粒加热的数值模型进行比较。这项研究具有广泛的广泛影响。在技​​术方面，它将为将等离子体作为功能性纳米颗粒的来源建立科学基础，以用于纳米技术。它还将作为许多教育和外展活动的跳板。其中包括通过当地公立学区的K-12宣传；本科生参与研究；在高度跨学科的研究环境中培训研究生和本科生；新的跨学科研究生课程的教学；促进妇女和代表不足的群体参与我们的研究生研究计划；并积极参与行业。