Scanning Electron Microscopy (SEM)
Scanning electron microscopy coupled to energy dispersive x-ray spectroscopy (SEM-EDX) is a useful tool to study atmospheric aerosols. The physical properties of each aerosol particle are determined with a high-resolution SEM image and the elements present in each aerosol are observed in the EDX spectrum.
Pictured to the right is the FEI Helios 650 Nanolab Dualbeam electron microscope the Ault Lab uses at Michigan's Center for Materials Characterization.
Figure caption: . Scanning electron microscopy images with 1 μm scale bars (left) and corresponding energy dispersive X-ray spectra (right) of representative individual particles defined as (A) Lake spray aerosol-Salt (B) Lake spray aerosol-Organic, and (C) Lake spray aerosol-Biological.
May, N. W.; Olson, N. E.G; Panas, M.; Axson, J. L.P; Tirella, P. S.U; Kirpes, R. M.; Craig, R. L.G; Gunsch, M. J.; China, S.; Laskin, A.; Ault, A. P.*; Pratt, K. A.*Aerosol Emissions from Great Lakes Harmful Algal Blooms, Environmental Science & Technology, 2018, 52 (2), 397-405. DOI: 10.1021/acs.estlett.8b00254
SEM-EDX can also be used to collect elemental maps that show the location of elements present in each aerosol particle.
Figure caption: SEM images and EDX elemental maps of representative: (A) sea spray aerosol (SSA) and (B) lake spray aerosol (LSA) particles collected at UMBS, as well as LSA generated in the laboratory from (C) Lake Superior and (D) Lake Michigan freshwater samples.
May, N. W.; Gunsch, M. J.; Olson, N. E.G; Bondy, A. L.G; Kirpes, R. M.; Bertman, S. B.; Swarup, C.; Laskin, A.; Hopke, P. K.; Ault, A. P.*; Pratt, K. A.* Unexpected contributions of sea spray and lake spray aerosol to inland particulate matter, Environmental Science and Technology Letters, 2018, 5 (7), 405–412.