Articles | Volume 26, issue 16
https://doi.org/10.5194/acp-26-12183-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-12183-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
In situ real-time determination of SO2 photochemical oxidation in nanoscale sea salt aerosols based on dark-field microscopy
Xijie Xiong
Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
Zhibo Xie
CORRESPONDING AUTHOR
Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
Xiuli Wei
Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
Douguo Zhang
Institute of Photonics, Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China
Jianguo Liu
Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
Huaqiao Gui
CORRESPONDING AUTHOR
Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
Institute of Environment, Hefei Comprehensive National Science Center, Hefei 231299, China
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Short summary
Using dark-field microscopy, we observed in situ reactions between individual sodium chloride nanoparticles and sulfur dioxide under ultraviolet irradiation. We found that reaction rates depended on particle size strongly and nonlinearly, with this behavior likely driven by the competition between surface curvature and specific surface area effects. This interpretation was further confirmed through transition state theory calculations and experimental modification of particle surface area.
Using dark-field microscopy, we observed in situ reactions between individual sodium chloride...
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