Articles | Volume 25, issue 14
https://doi.org/10.5194/acp-25-8061-2025
© Author(s) 2025. 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-25-8061-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Jul 2025
Research article |
| 28 Jul 2025
| 28 Jul 2025
Copper accelerates photochemically induced radical chemistry of iron-containing secondary organic aerosol (SOA)
Kevin Kilchhofer
CORRESPONDING AUTHOR
PSI Center for Energy and Environmental Sciences, Paul Scherrer Institute, 5232 Villigen, Switzerland
Department of Environmental System Science, Institute for Atmospheric and Climate Science, ETH Zurich, 8092 Zurich, Switzerland
now at: Physikalisch Meteorologisches Observatorium, World Radiation Center (PMOD/WRC), 7260 Davos, Switzerland
PSI Center for Energy and Environmental Sciences, Paul Scherrer Institute, 5232 Villigen, Switzerland
Laura Torrent
PSI Center for Energy and Environmental Sciences, Paul Scherrer Institute, 5232 Villigen, Switzerland
School of Architecture, Civil, and Environmental Engineering (ENAC IIE GR-LUD), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
now at: Department of Chemistry, Faculty of Sciences, University of Girona, 17003 Girona, Spain
Rico K. Y. Cheung
PSI Center for Energy and Environmental Sciences, Paul Scherrer Institute, 5232 Villigen, Switzerland
now at: Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
Peter A. Alpert
PSI Center for Energy and Environmental Sciences, Paul Scherrer Institute, 5232 Villigen, Switzerland
now at: XRnanotech, 5232 Villigen PSI, Switzerland
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Short summary
Aerosol particles composed of metal complexes generate radicals as a result of photochemical reactions. The reactive species generated are hazardous to human health. We report microscopy data with particles composed of an organic proxy exposed to UV light. We found that copper influenced the reoxidation and initial iron reduction via photolysis of the complex. New model results suggest that we need to account for decreased photochemical activity and use a copper-induced reoxidation reaction.
Aerosol particles composed of metal complexes generate radicals as a result of photochemical...
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