Nanosecond Pulse Discharges at a Liquid-Vapor Interface and in Liquids: Discharge Dynamics and Plasma Chemistry

这项工作将研究等离子体，等离子体是在液体表面附近和接近室温的液体中产生的电离气体的云或气泡。这种等离子体在生物和医学领域的几种新兴技术的发展方面具有巨大潜力，这些技术包括：从水中去除有机污染物、水的活化以进行灭菌和消毒、伤口愈合、皮肤癌治疗、在液体中合成纳米粒子以及清洁能源技术。这些等离子体的基本物理和化学过程尚不清楚，主要是由于缺乏准确的实验数据，而这些数据将在这项工作中获得。在这项研究中获得的结果将提高我们对这些过程的理解，并有望对低温等离子体在生物医学、医疗保健和清洁能源方面的应用产生重大影响。脉冲等离子体在液-气界面和液体中的基本动力学将采用以下方法进行研究：(1)测量液-气界面表面电离波等离子体的电场。这些数据将提供深入了解表面电离波的结构和动力学。（ii）近地表等离子体中电子密度和电子温度的测量。这些数据将量化输入能量在不同能量模式之间的分配。（iii）近表面液体层中溶剂化电子的测量。这些数据将显示电子是如何传输到液体表面并渗入液体的。这些测量还可以解决等离子体是否可以直接在液相中产生的基本问题。（iv）液-气界面附近等离子体中物质数密度的测量。这些结果将与动力学模型预测进行比较，以量化表面等离子体中的电场和电子能量对气相等离子体化学的影响。这项工作将对实验数据很少的瞬态液-气界面等离子体的动力学和动力学进行定量研究，并使对其行为的可靠预测成为可能。

This work will study plasmas, which are clouds or bubbles of ionized gas, produced near liquid surfaces and in liquids at near room temperatures. Such plasmas have significant potential for development of several emerging technologies in biology and medicine for removal of organic contaminants from water, activation of water for sterilization and disinfection, wound healing, skin cancer therapies, synthesis of nanoparticles in liquids, as well as clean energy technologies. Fundamental physical and chemical processes in these plasmas are poorly understood, primarily due to lack of accurate experimental data which will be obtained in this work. The results obtained during this study will improve our understanding of these processes and are expected to have a major impact on development of low-temperature plasmas for biomedical applications, healthcare, and clean energy.Fundamental kinetics of pulsed plasmas sustained at a liquid-vapor interface and in liquids will be studied using the following methods: (i) Measurements of electric field in surface ionization wave plasmas at a liquid-vapor interface. These data will provide insight into surface ionization wave structure and dynamics. (ii) Measurements of electron density and electron temperature in the near-surface plasma. These data will quantify input energy partition among different energy modes. (iii) Measurements of solvated electrons in the near-surface liquid layer. These data will show how electrons are transported to the liquid surface and penetrate into the liquid. These measurements may also resolve the fundamental question whether the plasma may be generated directly in the liquid phase. (iv) Measurements of species number densities in the plasma near the liquid-vapor interface. These results will be compared with kinetic modeling predictions to quantify the effect of electric field and electron energy in the surface plasma on vapor phase plasma chemistry. This work will yield quantitative insight into dynamics and kinetics of transient liquid-vapor interface plasmas for which there is little experimental data, and make possible confident prediction of their behavior.