%0 Journal Article
%A Breitenlechner, Martin
%A Fischer, Lukas
%A Hainer, Markus
%A Heinritzi, Martin
%A Curtius, Joachim
%A Hansel, Armin
%D 2017
%T PTR3: An Instrument for Studying the Lifecycle of
Reactive Organic Carbon in
the Atmosphere
%U https://acs.figshare.com/articles/journal_contribution/PTR3_An_Instrument_for_Studying_the_Lifecycle_of_Reactive_Organic_Carbon_in_the_Atmosphere/4996703
%R 10.1021/acs.analchem.6b05110.s001
%2 https://acs.figshare.com/ndownloader/files/8413016
%K reaction chamber
%K mass resolution
%K gas inlet
%K sample gas
%K proton transfer reaction-time-of-flight mass spectrometer
%K PTR-TOF-MS
%K volatility compounds
%K reaction time
%K SVOC
%K wall losses
%K water molecules
%K Reactive Organic Carbon
%K First calibration tests show sensitivities
%K sample gas flow
%K H 3 O
%K VOC
%K ppbv range
%K 18000 counts
%K reaction chamber design
%K product ions
%K volume
%K rf voltages
%K PTR 3 instrument
%K PTR-TOF
%K HOM
%X We have developed
and characterized the novel PTR3, a proton transfer
reaction-time-of-flight mass spectrometer (PTR-TOF) using a new gas
inlet and an innovative reaction chamber design. The reaction chamber
consists of a tripole operated with rf voltages generating an electric
field only in the radial direction. An elevated electrical field is
necessary to reduce clustering of primary hydronium (H3O+) and product ions with water molecules present in the
sample gas. The axial movement of the ions is achieved by the sample
gas flow only. Therefore, the new design allows a 30-fold longer reaction
time and a 40-fold increase in pressure compared to standard PTR-TOF-MS.
First calibration tests show sensitivities of up to 18000 counts per
second/parts per billion and volume (cps/ppbv) at a mass resolution
of >8000 m/Δm (fwhm). The
new inlet using center-sampling through a critical orifice reduces
wall losses of low volatility compounds. Therefore, the new PTR3 instrument
is sensitive to VOC typically present in the ppbv range as well as
to semivolatile organic compounds (SVOC) and even highly oxidized
organic molecules (HOMs) present in the parts per quadrillion per
volume (ppqv) range in the atmosphere.
%I ACS Publications