Dielectric barrier discharges applied for soft ionization and their mechanism

- Dielectric barrier discharge applied as desorption/ionization source.
- Dielectric barrier discharge applied solely as ionization source.
- Different geometries in order to maintain soft ionization.
- Characterization of the LTP probe.
- Dielectric barrier discharges with two dielectric barriers (ring-ring shape).

Dielectric barrier discharges are used for analytical applications as dissociative source for optical emission spectrometry and for ambient-ionization techniques. In the range of ambient-ionization techniques it has attracted much attention in fields like food safety, biological analysis, mass spectrometry for reaction monitoring and imaging forensic identification. In this review some examples are given for the application as desorption/ionization source as well as for the sole application as ionization source with different sample introductions. It will be shown that the detection might depend on the certain distance of the plasma in reference to the sample or the kind of discharge which might be produced by different shapes of the applied high voltage. Some attempts of characterization are presented. A more detailed characterization of the dielectric barrier discharge realized with two ring electrodes, each separately covered with a dielectric layer, is described.

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