Surface composition of size-selected sea salt particles under the influence of organic acids studied in situ using synchrotron radiation X-ray photoelectron spectroscopy
|Author:||Patanen, Minna1; Unger, Isaak2,3; Saak, Clara-Magdalena2,4;|
1Nano and Molecular Systems Research Unit, Faculty of Science, University of Oulu, P. O. Box 3000, Finland
2Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
3Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22763 Hamburg, Germany
4University of Vienna, Department of Physical Chemistry, Währinger Straße 42, 1090 Vienna, Austria
5Department of Cell and Molecular Biology, Uppsala University, Box 596, 75124 Uppsala, Sweden
6Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden
7Bolin Centre for Climate Research, 10691 Stockholm, Sweden
|Online Access:||PDF Full Text (PDF, 0.7 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2022082456079
Royal Society of Chemistry,
|Publish Date:|| 2022-08-24
Sea spray aerosols play a key role in the climate system by scattering solar radiation and by serving as cloud condensation nuclei. Despite their importance, the impact of sea spray aerosols on global climate remains highly uncertain. One of the key knowledge gaps in our understanding of sea spray aerosol is the chemical composition of the particle surface, important for various atmospheric chemical processes, as a function of size and bulk composition. Here, we have applied X-ray photoelectron spectroscopy (XPS) to determine the surface composition of both pure inorganic sea salt aerosols and sea salt aerosols spiked with an amino acid (phenylalanine) and a straight chain fatty acid (octanoic acid). Importantly, the use of a differential mobility analyser allowed size-selection of 150, 250 and 350 nm monodisperse aerosol particles for comparison to polydisperse aerosol particles. We observed enrichment of magnesium at the particle surfaces relative to chloride in all aerosols tested, across all particle sizes. Interestingly, the magnitude of this enrichment was dependent on the type of organic present in the solution as well as the particle size. Our results suggest that the observed enrichment in magnesium is an inorganic effect which can be either enhanced or diminished by the addition of organic substances.
Environmental science. Atmospheres
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
114 Physical sciences
116 Chemical sciences
1172 Environmental sciences
M. P. acknowledges the Academy of Finland for financial support. M. S. was financed by the Swedish Research Council (project number 2016-05100). P. Z. acknowledges funding form the Swedish Research Council Starting Grant 2018-05045. O. B. acknowledges the support by the Swedish Research Council (grant 2017-04162). I. U. acknowledges the support from the Carl Tryggers Foundation and thanks Stephan Thürmer for his data analysis routines, which have been used for the data analysis. The research leading to this result has been supported by the project CALIPSOplus under Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. We acknowledge SOLEIL for provision of synchrotron radiation facilities (proposal 20170532) and we thank Aleksandar Milosavljević for assistance in using the PLÉIADES beamline.
© 2022 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.