Anion-catalyzed dissolution of NO2 on aqueous microdroplets

A. Yabushita, S. Enami, Y. Sakamoto, M. Kawasaki, M. R. Hoffmann, A. J. Colussi

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

Fifty-seven years after NOx (NO + NO2) were identified as essential components of photochemical smog, atmospheric chemical models fail to correctly predict ·OH/HO2« concentrations under NOx-rich conditions. This deficiency is due, in part, to the uncertain rates and mechanism for the reactive dissolution of NO2(g) (2NO2 + H2O = NO3- + H+ + HONO) in fog and aerosol droplets. Thus, state-of-the-art models parametrize the uptake of NO2 by atmospheric aerosol from data obtained on "deactivated tunnel wall residue". Here, we report experiments in which NO3- production on the surface of microdroplets exposed to NO2(g) for ∼1ms is monitored by online thermospray mass spectrometry. NO2 does not dissolve in deionized water (NO3- signals below the detection limit) but readily produces NO3- on aqueous NaX (X = Cl, Br, I) microdroplets with NO2 uptake coefficients y that vary nonmonotonically with electrolyte concentration and peak at ymax ~ 10-4 for [NaX] ~ 1 mM, which is > 103 larger than that in neat water. Since I- is partially oxidized to I/in this process, anions seem to capture NO2(g) into X-NO/- radical anions for further reaction at the air/ water interface. By showing that y is strongly enhanced by electrolytes, these results resolve outstanding discrepancies between previous measurements in neat water versus NaCl-seeded clouds. They also provide a general mechanism for the heterogeneous conversion of NO2(g) to (NO3- + HONO) on the surface of aqueous media.

Original languageEnglish
Pages (from-to)4844-4848
Number of pages5
JournalJournal of Physical Chemistry A
Volume113
Issue number17
DOIs
Publication statusPublished - Apr 30 2009
Externally publishedYes

Fingerprint

Anions
dissolving
Dissolution
anions
Electrolytes
Water
water
Atmospheric aerosols
aerosols
Deionized water
electrolytes
Fog
smog
Aerosols
fog
Mass spectrometry
Tunnels
tunnels
mass spectroscopy
Air

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry

Cite this

Yabushita, A., Enami, S., Sakamoto, Y., Kawasaki, M., Hoffmann, M. R., & Colussi, A. J. (2009). Anion-catalyzed dissolution of NO2 on aqueous microdroplets. Journal of Physical Chemistry A, 113(17), 4844-4848. https://doi.org/10.1021/jp900685f

Anion-catalyzed dissolution of NO2 on aqueous microdroplets. / Yabushita, A.; Enami, S.; Sakamoto, Y.; Kawasaki, M.; Hoffmann, M. R.; Colussi, A. J.

In: Journal of Physical Chemistry A, Vol. 113, No. 17, 30.04.2009, p. 4844-4848.

Research output: Contribution to journalArticle

Yabushita, A, Enami, S, Sakamoto, Y, Kawasaki, M, Hoffmann, MR & Colussi, AJ 2009, 'Anion-catalyzed dissolution of NO2 on aqueous microdroplets', Journal of Physical Chemistry A, vol. 113, no. 17, pp. 4844-4848. https://doi.org/10.1021/jp900685f
Yabushita A, Enami S, Sakamoto Y, Kawasaki M, Hoffmann MR, Colussi AJ. Anion-catalyzed dissolution of NO2 on aqueous microdroplets. Journal of Physical Chemistry A. 2009 Apr 30;113(17):4844-4848. https://doi.org/10.1021/jp900685f
Yabushita, A. ; Enami, S. ; Sakamoto, Y. ; Kawasaki, M. ; Hoffmann, M. R. ; Colussi, A. J. / Anion-catalyzed dissolution of NO2 on aqueous microdroplets. In: Journal of Physical Chemistry A. 2009 ; Vol. 113, No. 17. pp. 4844-4848.
@article{8343fd43237d48aab3d84b4f83b34553,
title = "Anion-catalyzed dissolution of NO2 on aqueous microdroplets",
abstract = "Fifty-seven years after NOx (NO + NO2) were identified as essential components of photochemical smog, atmospheric chemical models fail to correctly predict ·OH/HO2« concentrations under NOx-rich conditions. This deficiency is due, in part, to the uncertain rates and mechanism for the reactive dissolution of NO2(g) (2NO2 + H2O = NO3- + H+ + HONO) in fog and aerosol droplets. Thus, state-of-the-art models parametrize the uptake of NO2 by atmospheric aerosol from data obtained on {"}deactivated tunnel wall residue{"}. Here, we report experiments in which NO3- production on the surface of microdroplets exposed to NO2(g) for ∼1ms is monitored by online thermospray mass spectrometry. NO2 does not dissolve in deionized water (NO3- signals below the detection limit) but readily produces NO3- on aqueous NaX (X = Cl, Br, I) microdroplets with NO2 uptake coefficients y that vary nonmonotonically with electrolyte concentration and peak at ymax ~ 10-4 for [NaX] ~ 1 mM, which is > 103 larger than that in neat water. Since I- is partially oxidized to I/in this process, anions seem to capture NO2(g) into X-NO/- radical anions for further reaction at the air/ water interface. By showing that y is strongly enhanced by electrolytes, these results resolve outstanding discrepancies between previous measurements in neat water versus NaCl-seeded clouds. They also provide a general mechanism for the heterogeneous conversion of NO2(g) to (NO3- + HONO) on the surface of aqueous media.",
author = "A. Yabushita and S. Enami and Y. Sakamoto and M. Kawasaki and Hoffmann, {M. R.} and Colussi, {A. J.}",
year = "2009",
month = "4",
day = "30",
doi = "10.1021/jp900685f",
language = "English",
volume = "113",
pages = "4844--4848",
journal = "Journal of Physical Chemistry A",
issn = "1089-5639",
publisher = "ACS Publications",
number = "17",

}

TY - JOUR

T1 - Anion-catalyzed dissolution of NO2 on aqueous microdroplets

AU - Yabushita, A.

AU - Enami, S.

AU - Sakamoto, Y.

AU - Kawasaki, M.

AU - Hoffmann, M. R.

AU - Colussi, A. J.

PY - 2009/4/30

Y1 - 2009/4/30

N2 - Fifty-seven years after NOx (NO + NO2) were identified as essential components of photochemical smog, atmospheric chemical models fail to correctly predict ·OH/HO2« concentrations under NOx-rich conditions. This deficiency is due, in part, to the uncertain rates and mechanism for the reactive dissolution of NO2(g) (2NO2 + H2O = NO3- + H+ + HONO) in fog and aerosol droplets. Thus, state-of-the-art models parametrize the uptake of NO2 by atmospheric aerosol from data obtained on "deactivated tunnel wall residue". Here, we report experiments in which NO3- production on the surface of microdroplets exposed to NO2(g) for ∼1ms is monitored by online thermospray mass spectrometry. NO2 does not dissolve in deionized water (NO3- signals below the detection limit) but readily produces NO3- on aqueous NaX (X = Cl, Br, I) microdroplets with NO2 uptake coefficients y that vary nonmonotonically with electrolyte concentration and peak at ymax ~ 10-4 for [NaX] ~ 1 mM, which is > 103 larger than that in neat water. Since I- is partially oxidized to I/in this process, anions seem to capture NO2(g) into X-NO/- radical anions for further reaction at the air/ water interface. By showing that y is strongly enhanced by electrolytes, these results resolve outstanding discrepancies between previous measurements in neat water versus NaCl-seeded clouds. They also provide a general mechanism for the heterogeneous conversion of NO2(g) to (NO3- + HONO) on the surface of aqueous media.

AB - Fifty-seven years after NOx (NO + NO2) were identified as essential components of photochemical smog, atmospheric chemical models fail to correctly predict ·OH/HO2« concentrations under NOx-rich conditions. This deficiency is due, in part, to the uncertain rates and mechanism for the reactive dissolution of NO2(g) (2NO2 + H2O = NO3- + H+ + HONO) in fog and aerosol droplets. Thus, state-of-the-art models parametrize the uptake of NO2 by atmospheric aerosol from data obtained on "deactivated tunnel wall residue". Here, we report experiments in which NO3- production on the surface of microdroplets exposed to NO2(g) for ∼1ms is monitored by online thermospray mass spectrometry. NO2 does not dissolve in deionized water (NO3- signals below the detection limit) but readily produces NO3- on aqueous NaX (X = Cl, Br, I) microdroplets with NO2 uptake coefficients y that vary nonmonotonically with electrolyte concentration and peak at ymax ~ 10-4 for [NaX] ~ 1 mM, which is > 103 larger than that in neat water. Since I- is partially oxidized to I/in this process, anions seem to capture NO2(g) into X-NO/- radical anions for further reaction at the air/ water interface. By showing that y is strongly enhanced by electrolytes, these results resolve outstanding discrepancies between previous measurements in neat water versus NaCl-seeded clouds. They also provide a general mechanism for the heterogeneous conversion of NO2(g) to (NO3- + HONO) on the surface of aqueous media.

UR - http://www.scopus.com/inward/record.url?scp=65649098384&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=65649098384&partnerID=8YFLogxK

U2 - 10.1021/jp900685f

DO - 10.1021/jp900685f

M3 - Article

C2 - 19331373

AN - SCOPUS:65649098384

VL - 113

SP - 4844

EP - 4848

JO - Journal of Physical Chemistry A

JF - Journal of Physical Chemistry A

SN - 1089-5639

IS - 17

ER -