Ionic Strength Effect on Photochemistry of Fluorene and Dimethylsulfoxide at the Air-Sea Interface: Alternative Formation Pathway of Organic Sulfur Compounds in a Marine Atmosphere
Ionic Strength Effect on Photochemistry of Fluorene and Dimethylsulfoxide at the Air-Sea Interface: Alternative Formation Pathway of Organic Sulfur Compounds in a Marine Atmosphere
复制标题
离子强度对气海界面芴和二甲基亚砜光化学的影响：海洋大气中有机硫化合物的替代形成途径
DOI：
10.1021/acsearthspacechem.0c00059
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发表时间：
2020
影响因子：
3.4
通讯作者：
Gligorovski Sasho
中科院分区：
文献类型：
--
作者：
Mekic Majda;Zeng Jiafa;Zhou Wentao;Loisel Gwendal;Jin Biao;Li Xue;Vione Davide;Gligorovski Sasho
The photochemical transformation processes occurring at the sea surface lead to the formation of low volatility organic compounds that contribute to new particle formation in the marine boundary layer. Here, we suggest an alternative formation pathway of organosulfur and oxygenated aliphatic compounds, initiated by sunlight-activated fluorene (FL) and dimethylsulfoxide (DMSO) in the presence of the halide ions Cl–, Br–, and I–. In particular, we observe a prompt formation of four typical precursors of secondary organic aerosols, methanesulfonic acid (CH3SO3H), methanesulfinic acid (CH3SO2H), hydroxymethanesulfonic acid (CH4O4S, MSAOH), and 2-hydroxyethenesulfonic acid (C2H5O4SH), upon light irradiation of FL/DMSO. The photochemical modeling shows that in the summer period, MSAOH would be formed in just a few hours under fair-weather conditions, which makes the photosensitized chemistry of FL toward DMSO potentially significant. We also show that the sunlight-initiated degradation of FL is considerably faster in the presence of halide ions, compared to its photochemical degradation in the dilute aqueous phase. Therefore, the photochemical degradation of FL and potentially other polycyclic aromatic hydrocarbons would be faster in high ionic strength aerosol particles, compared to analogous diluted aqueous-phase photochemical processes occurring in, for example, clouds. This could considerably affect the absorbing properties of the aerosols, which should be considered in future modeling studies.
