TY  - JOUR
A1  - Wang, Mingyi
A1  - He, Xu-Cheng
A1  - Finkenzeller, Henning
A1  - Iyer, Siddharth
A1  - Chen, Dexian
A1  - Shen, Jiali
A1  - Simon, Mario
A1  - Hofbauer, Victoria
A1  - Kirkby, Jasper
A1  - Curtius, Joachim
A1  - Maier, Norbert
A1  - Kurtén, Theo
A1  - Worsnop, Douglas R.
A1  - Kulmala, Markku
A1  - Rissanen, Matti P.
A1  - Volkamer, Rainer
A1  - Tham, Yee Jun
A1  - Donahue, Neil McPherson
A1  - Sipilä, Mikko
T1  - Measurement of iodine species and sulfuric acid using bromide chemical ionization mass spectrometers
T2  - Atmospheric measurement techniques
N2  - Iodine species are important in the marine atmosphere for oxidation and new-particle formation. Understanding iodine chemistry and iodine new-particle formation requires high time resolution, high sensitivity, and simultaneous measurements of many iodine species. Here, we describe the application of a bromide chemical ionization mass spectrometer (Br-CIMS) to this task. During the iodine oxidation experiments in the Cosmics Leaving OUtdoor Droplets (CLOUD) chamber, we have measured gas-phase iodine species and sulfuric acid using two Br-CIMS, one coupled to a Multi-scheme chemical IONization inlet (Br-MION-CIMS) and the other to a Filter Inlet for Gasses and AEROsols inlet (Br-FIGAERO-CIMS). From offline calibrations and intercomparisons with other instruments, we have quantified the sensitivities of the Br-MION-CIMS to HOI, I2, and H2SO4 and obtained detection limits of 5.8 × 106, 3.8 × 105, and 2.0 × 105 molec. cm−3, respectively, for a 2 min integration time. From binding energy calculations, we estimate the detection limit for HIO3 to be 1.2 × 105 molec. cm−3, based on an assumption of maximum sensitivity. Detection limits in the Br-FIGAERO-CIMS are around 1 order of magnitude higher than those in the Br-MION-CIMS; for example, the detection limits for HOI and HIO3 are 3.3 × 107 and 5.1 × 106 molec. cm−3, respectively. Our comparisons of the performance of the MION inlet and the FIGAERO inlet show that bromide chemical ionization mass spectrometers using either atmospheric pressure or reduced pressure interfaces are well-matched to measuring iodine species and sulfuric acid in marine environments.
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/73486
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-734862
SN  - 1867-8548
N1  - This research has been funded by the US National Science Foundation (grant nos. AGS-1531284, AGS-1801574 and AGS-1801280), the Academy of Finland (grant nos. 296628, 328290, Centre of Excellence 1118615), and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (GASPARCON; grant no. 714621). The FIGAERO-CIMS was supported by an MRI grant for the US NSF (grant no. AGS-1531284), as well as the Wallace Research Foundation.

Open-access funding was provided by the Helsinki University Library.
N1  - Data available on request from the authors.
VL  - 14
IS  - 6
SP  - 4187
EP  - 4202
PB  - Copernicus
CY  - Katlenburg-Lindau
ER  -