TY - JOUR
T1 - Spontaneous dark formation of OH radicals at the interface of aqueous atmospheric droplets
AU - Li, Kangwei
AU - Guo, Yunlong
AU - Nizkorodov, Sergey A.
AU - Rudich, Yinon
AU - Angelaki, Maria
AU - Wang, Xinke
AU - An, Taicheng
AU - Perrier, Sebastien
AU - George, Christian
N1 - This study was supported by the European Research Council (ERC) under the Horizon 2020 research and innovation program/ERC Grant Agreement 101052601—Spontaneous interfacial oxidant formation as a key driver for aerosol oxidation (SOFA). T.A. and Y.G. acknowledge the financial support from the National Natural Science Foundation of China (42020104001 and 42007192). Y.R. acknowledges partial support by the Israel Science Foundation with grant #928/21. K.L. and C.G. are extremely grateful to D.J. Donaldson, University of Toronto, for critically reading the manuscript and helpful discussion. Author contributions - K.L., S.A.N., Y.R., X.W., S.P., and C.G. designed research; K.L., Y.G., M.A., and S.P. performed research; K.L., Y.G., S.A.N., Y.R., X.W., S.P., and C.G. analyzed data; and K.L., Y.G., S.A.N., Y.R., X.W., T.A., S.P., and C.G. wrote the paper.
PY - 2023/4/11
Y1 - 2023/4/11
N2 - Hydroxyl radical (OH) is a key oxidant that triggers atmospheric oxidation chemistry in both gas and aqueous phases. The current understanding of its aqueous sources is mainly based on known bulk (photo)chemical processes, uptake from gaseous OH, or related to interfacial O 3 and NO 3 radical-driven chemistry. Here, we present experimental evidence that OH radicals are spontaneously produced at the air–water interface of aqueous droplets in the dark and the absence of known precursors, possibly due to the strong electric field that forms at such interfaces. The measured OH production rates in atmospherically relevant droplets are comparable to or significantly higher than those from known aqueous bulk sources, especially in the dark. As aqueous droplets are ubiquitous in the troposphere, this interfacial source of OH radicals should significantly impact atmospheric multiphase oxidation chemistry, with substantial implications on air quality, climate, and health.
AB - Hydroxyl radical (OH) is a key oxidant that triggers atmospheric oxidation chemistry in both gas and aqueous phases. The current understanding of its aqueous sources is mainly based on known bulk (photo)chemical processes, uptake from gaseous OH, or related to interfacial O 3 and NO 3 radical-driven chemistry. Here, we present experimental evidence that OH radicals are spontaneously produced at the air–water interface of aqueous droplets in the dark and the absence of known precursors, possibly due to the strong electric field that forms at such interfaces. The measured OH production rates in atmospherically relevant droplets are comparable to or significantly higher than those from known aqueous bulk sources, especially in the dark. As aqueous droplets are ubiquitous in the troposphere, this interfacial source of OH radicals should significantly impact atmospheric multiphase oxidation chemistry, with substantial implications on air quality, climate, and health.
UR - http://www.scopus.com/inward/record.url?scp=85151737827&partnerID=8YFLogxK
U2 - 10.1073/pnas.2220228120
DO - 10.1073/pnas.2220228120
M3 - مقالة
C2 - 37011187
SN - 0027-8424
VL - 120
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 15
M1 - e2220228120
ER -