Skip to Main content Skip to Navigation
New interface
Journal articles

The gas-phase formation mechanism of iodic acid as an atmospheric aerosol source

Abstract : Abstract Iodine is a reactive trace element in atmospheric chemistry that destroys ozone and nucleates particles. Iodine emissions have tripled since 1950 and are projected to keep increasing with rising O 3 surface concentrations. Although iodic acid (HIO 3 ) is widespread and forms particles more efficiently than sulfuric acid, its gas-phase formation mechanism remains unresolved. Here, in CLOUD atmospheric simulation chamber experiments that generate iodine radicals at atmospherically relevant rates, we show that iodooxy hypoiodite, IOIO, is efficiently converted into HIO 3 via reactions (R1) IOIO + O 3 → IOIO 4 and (R2) IOIO 4 + H 2 O → HIO 3 + HOI + (1) O 2 . The laboratory-derived reaction rate coefficients are corroborated by theory and shown to explain field observations of daytime HIO 3 in the remote lower free troposphere. The mechanism provides a missing link between iodine sources and particle formation. Because particulate iodate is readily reduced, recycling iodine back into the gas phase, our results suggest a catalytic role of iodine in aerosol formation.
Document type :
Journal articles
Complete list of metadata

https://hal.univ-reunion.fr/hal-03859649
Contributor : Jérome Brioude Connect in order to contact the contributor
Submitted on : Wednesday, November 23, 2022 - 9:22:00 AM
Last modification on : Thursday, November 24, 2022 - 3:41:53 AM

File

s41557-022-01067-z-1.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Henning Finkenzeller, Siddharth Iyer, Xu-Cheng He, Mario Simon, Theodore Koenig, et al.. The gas-phase formation mechanism of iodic acid as an atmospheric aerosol source. Nature Chemistry, 2022, ⟨10.1038/s41557-022-01067-z⟩. ⟨hal-03859649⟩

Share

Metrics

Record views

0

Files downloads

0