Fundamental Investigations on the Plasma Chemistry in Dielectric Barrier Discharges Operated with Air-Water Vapor Mixtures at Sub-Atmospheric Pressure

该项目的目的是调查的基本等离子体化学反应机制，导致活性氧和氮物种（RONS）的控制产生介质阻挡放电（DBD）操作接近或在大气压力下与氩气，空气和水蒸气的混合物。因此，一种新型的亚大气压低温介质阻挡放电，称为文丘里蒸汽DBD，采用。它允许在20至1000毫巴的压力范围内用空气/水蒸气混合物操作产生反应性等离子体，并且使得可以通过文丘里泵将等离子体产生的RONS从低于大气压的放电区转移到大气压。放电行为和等离子体动力学的分析将进行大范围的放电参数，使用光谱和电气测量结合数值模拟。调查将提供一个详细的了解的先决条件和潜在的反应机制，导致一个稳定的和可重复的操作文丘里蒸汽DBD。此外，它们还将提供关于操作参数和所用气体混合物对操作制度、等离子体动力学和等离子体成分的影响的基本信息，重点是臭氧、氮氧化物和水基物质亚硝酸和过氧化氢。特别地，要确定分别发生臭氧主导、氮氧化物主导和过氧化氢主导的等离子体化学的那些操作条件。

The project aims at the investigation of the fundamental plasma-chemical reaction mechanisms leading to the controlled generation of reactive oxygen and nitrogen species (RONS) in dielectric barrier discharges (DBD) operating near or at atmospheric pressure with mixtures of argon, air and water vapor. Therefore, a novel type of sub-atmospheric pressure low-temperature dielectric barrier discharge, termed Venturi-Vapor-DBD, is employed. It allows the generation of reactive plasma operating with air/water vapor mixtures in the pressure range from 20 to 1000 mbar and makes it possible to transfer the plasma-generated RONS from a sub-atmospheric pressure discharge zone to atmospheric pressure by means of a Venturi pump. The analysis of the discharge behavior and plasma dynamics will be performed for a large range of discharge parameters using spectroscopic and electrical measurements in combination with numerical modeling. The investigations will provide a detailed understanding of the prerequisites and underlying reaction mechanisms leading to a stable and reproducible operation of Venturi-Vapor-DBDs. Furthermore, they will make basic information available on the impact of the operating parameters and gas mixtures used on the operating regime, the plasma dynamics and the plasma composition with the focus on ozone, nitrogen oxides and the water-based species nitrous acid and hydrogen peroxide. In particular, those operating conditions are to be determined at which an ozone-dominated, a nitrogen oxide-dominated and a hydrogen peroxide-dominated, respectively, plasma chemistry occurs.