Tropospheric Chemistry: VOC Instruments

Proton-Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS)

Principle of the Measurement

Chemical ionization of VOCs by proton transfer with hydronium ions (H₃O⁺)
Detection using a high-resolution time-of-flight mass spectrometer

Species Measured

1. Aromatics
2. Biogenic VOCs (isoprene, monoterpenes)
3. Alcohols
4. Ketones
5. Acids
6. Aldehydes
7. Nitriles
8. Dimethyl sulfide

Time Response / Detection Limit

1 second / 10-100 pptv

Manufacturer

Aerodyne Research Inc (modified)

Field Projects

Deployed onboard the NOAA WP-3D, the CSL mobile laboratory, and at ground sites.

• Secondary organic aerosol Chamber Experiments for Non-Traditional Species (SCENTS) 2022
• Shale Oil and Natural Gas Nexus (SONGNEX) 2015

Key Publications

Yuan, B., A. Koss, C. Warneke, J. B. Gilman, B. M. Lerner, H. Stark, and J. A. de Gouw, A high-resolution time-of-flight chemical ionization mass spectrometer utilizing hydronium ions (H3O+ ToF-CIMS) for measurements of volatile organic compounds in the atmosphere, Atmospheric Measurement Techniques, doi:10.5194/amt-9-2735-2016, 2016.

Koss, A. R., C. Warneke, B. Yuan, M. M. Coggon, P. R. Veres, and J. A. de Gouw, Evaluation of NO+ reagent ion chemistry for on-line measurements of atmospheric volatile organic compounds, Atmospheric Measurement Techniques, doi:10.5194/amt-9-2909-2016, 2016.