E7.1 - Fast ion-selective ppb-level gas sensor based on pulsed atmospheric pressure chemical ionization and ion-ionrecombination
- AMA Conferences 2015
2015-05-19 - 2015-05-21
- Proceedings SENSOR 2015
- E7 - Gas Sensors III
- A. Heptner, N. Angerstein, S. Zimmermann - Leibniz University Hannover (Germany)
- 698 - 703
Investigating the ion-ion-recombination rate of different analytes at atmospheric pressure reveals that ion species can be separated by their ion specific recombination rates. This effect is utilized for the development of a novel gas sensor: A gas mixture is ionized by atmospheric pressure chemical ionization (APCI) for a defined ionization time. At the end of the ionization the generated ion species recombine leading to a decreasing ion density with an increasing recombination time. The measured ion density at different times leads to characteristic decay curves depending on the ion species present and thus on the gas composition. From this decay curves analytes can be identified and analyte concentrations down to ppb-levels can be detected.