Elucidation of excitation mechanisms which lead to homogeneous and filamentary modes of a dielectric barrier driven plasma-jet

阐明导致介电势垒驱动等离子体射流的均匀和丝状模式的激发机制

• 批准号: 262732688
• 负责人: Privatdozent Dr. Joachim Franzke
• 金额: --
• 依托单位: Leibniz-Institut für Analytische Wissenschaften -ISAS- e.V.
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/262732688?language=en
• 关键词: Elucidation; excitation; mechanisms; lead; homogeneous

In recent years dielectric barrier discharges were applied both for Ambient Air Ionisation and for soft ionization of organic molecules. Most of the applied discharges differ in the homogeneous and filamentary operation mode. In the case of the operation in a homogeneous mode the ionization efficiency is 1000 times higher than in the case of the filamentary one. Therefore, in this research project the excitation mechanisms, which lead to different operation modes, should be elucidated in order to increase the effectivity of the ionisation.In the first step, the influence of the air, which is around the plasma-jet, will be investigated by a comparison with He as surrounding gas both in the homogeneous and the filamentary mode with the help of a spatially resolved measurement. After the ignition of a plasma the divergence of the gas-flow which leaves the capillary will be changed. When the Divergence is also changed when the operation mode is changed from homogeneous to filamentary this might be an explanation for the decrease of the Ionisation efficiency.It can be expected that in an homogeneous He plasma the majority of ions consists of N2+ ions whereas in a filamentary plasma also or even more He2+ as well as He+ ions will be present. In a He plasma the existence of He2+ as well as He+ is hard or even not possible to detect by optical spectroscopy and by mass spectrometry it cannot be measured spatially dependent. Therefore, with the help of a model system consisting of Ar and low concentrations of ammonia and Fluor the assumption will be inspected.Furthermore, with the help of time-resolved measurements it will be investigated if the plasma-jet, as often stated, is really an afterglow or if both plasmas, the electrode plasma and the plasma-jet can be seen as two coupled plasmas. This will be investigated for different polarisations and in dependence on the applied voltage.

近年来，介质阻挡放电被应用于环境空气电离和有机分子的软电离。大多数应用的放电在均匀和丝状操作模式上有所不同。在均质模式操作的情况下，电离效率比丝状模式高 1000 倍。因此，在本研究项目中，应阐明导致不同操作模式的激发机制，以提高电离的有效性。第一步，等离子射流周围空气的影响将借助空间分辨测量，通过在均质模式和丝状模式下与周围气体 He 进行比较来进行研究。等离子体点燃后，离开毛细管的气流的发散度将发生变化。 当操作模式从均质变为丝状时发散度也发生变化，这可能是电离效率降低的解释。可以预期，在均质 He 等离子体中，大多数离子由 N2+ 离子组成，而在还会存在丝状等离子体，甚至更多的 He2+ 以及 He+ 离子。在 He 等离子体中，He2+ 以及 He+ 的存在很难甚至不可能通过光谱法检测到，而通过质谱法则无法在空间上进行测量。因此，在由 Ar 和低浓度氨和氟组成的模型系统的帮助下，将检查该假设。此外，在时间分辨测量的帮助下，将研究等离子射流（如通常所述）是否是实际上是余辉，或者如果两个等离子体、电极等离子体和等离子体射流都可以被视为两个耦合等离子体。这将针对不同的极化以及所施加的电压进行研究。

项目成果

Systematic Comparison between Half and Full Dielectric Barrier Discharges Based on the Low Temperature Plasma Probe (LTP) and Dielectric Barrier Discharge for Soft Ionization (DBDI) Configurations.

基于低温等离子体探针 (LTP) 和软电离介质阻挡放电 (DBDI) 配置的半介质阻挡放电和全介质阻挡放电的系统比较。

• DOI: 10.1021/acs.analchem.7b02174
• 发表时间: 2017-08-07
• 期刊: Analytical chemistry
• 影响因子: 7.4
• 作者: F. Klute;Sebastian Br;t;t;Pascal Vogel;B. Biskup;Charlotte Reininger;V. Horvatić;C. Vadla;P. B. Farnsworth;J. Franzke
• 通讯作者: J. Franzke

Capillary Dielectric Barrier Discharge: Transition from Soft Ionization to Dissociative Plasma.

毛细管介质阻挡放电：从软电离到解离等离子体的转变。

• DOI: 10.1021/acs.analchem.5b04605
• 发表时间: 2016-04-11
• 期刊: Analytical chemistry
• 影响因子: 7.4
• 作者: F. Klute;A. Michels;A. Schütz;C. Vadla;V. Horvatić;J. Franzke
• 通讯作者: J. Franzke

Tuning Soft Ionization Strength for Organic Mass Spectrometry.

调整有机质谱的软电离强度。

• DOI: 10.1021/acs.analchem.6b01131
• 发表时间: 2016-05-05
• 期刊: Analytical chemistry
• 影响因子: 7.4
• 作者: A. Schütz;F. Klute;Sebastian Br;t;t;Sascha Liedtke;G. Jestel;J. Franzke
• 通讯作者: J. Franzke

Soft Argon-Propane Dielectric Barrier Discharge Ionization.

软氩丙烷介质阻挡放电电离。

• DOI: 10.1021/acs.analchem.7b05390
• 发表时间: 2018-02-20
• 期刊: Analytical chemistry
• 影响因子: 7.4
• 作者: A. Schütz;Felipe J. Lara;F. Klute;Sebastian Br;t;t;M. Schilling;A. Michels;D. Veẑa;V. Horvatić;J. García;J. Franzke
• 通讯作者: J. Franzke

An experimental study on the influence of trace impurities on ionization of atmospheric noble gas dielectric barrier discharges.

微量杂质对大气惰性气体介质阻挡放电电离影响的实验研究

• DOI: 10.1039/c6an01352j
• 发表时间: 2016-10-03
• 期刊: The Analyst
• 作者: F. Klute;A. Schütz;A. Michels;C. Vadla;D. Veẑa;V. Horvatić;J. Franzke
• 通讯作者: J. Franzke