Hostname: page-component-84b7d79bbc-x5cpj Total loading time: 0 Render date: 2024-07-28T20:30:39.190Z Has data issue: false hasContentIssue false

Derivation of Optical Properties of Carbonaceous Aerosols by Monochromated Electron Energy-Loss Spectroscopy

Published online by Cambridge University Press:  15 April 2014

Jiangtao Zhu
Affiliation:
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA
Peter A. Crozier*
Affiliation:
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA
Peter Ercius
Affiliation:
Lawrence Berkeley National Laboratory, National Center for Electron Microscopy, Berkeley, CA 94720, USA
James R. Anderson
Affiliation:
School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA
*
*Corresponding author.crozier@asu.edu
Get access

Abstract

Monochromated electron energy-loss spectroscopy (EELS) is employed to determine the optical properties of carbonaceous aerosols from the infrared to the ultraviolet region of the spectrum. It is essential to determine their optical properties to understand their accurate contribution to radiative forcing for climate change. The influence of surface and interface plasmon effects on the accuracy of dielectric data determined from EELS is discussed. Our measurements show that the standard thin film formulation of Kramers−Kronig analysis can be employed to make accurate determination of the dielectric function for carbonaceous particles down to about 40 nm in size. The complex refractive indices of graphitic and amorphous carbon spherules found in the atmosphere were determined over the wavelength range 200–1,200 nm. The graphitic carbon was strongly absorbing black carbon, whereas the amorphous carbon shows a more weakly absorbing brown carbon profile. The EELS approach provides an important tool for exploring the variation in optical properties of atmospheric carbon.

Type
EDGE Special Issue
Copyright
© Microscopy Society of America 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alexander, D.T.L., Crozier, P.A. & Anderson, J.R. (2008). Brown carbon spheres in East Asian outflow and their optical properties. Science 321(5890), 833836.Google Scholar
Andreae, M.O. & Gelencser, A. (2006). Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols. Atmos Chem Phys 6, 31313148.CrossRefGoogle Scholar
Bergstrom, R.W., Russell, P.B. & Hignett, P. (2002). Wavelength dependence of the absorption of black carbon particles: Predictions and results from the TARFOX experiment and implications for the aerosol single scattering albedo. J Atmos Sci 59(3), 567577.Google Scholar
Bond, T.C. & Bergstrom, R.W. (2006). Light absorption by carbonaceous particles: An investigative review. Aerosol Sci Tech 40(1), 2767.CrossRefGoogle Scholar
Bond, T.C., Doherty, S.J., Fahey, D.W., Forster, P.M., Berntsen, T., DeAngelo, B.J., Flanner, M.G., Ghan, S., Kärcher, B., Koch, D., Kinne, S., Kondo, Y., Quinn, P.K., Sarofim, M.C., Schultz, M.G., Schulz, M., Venkataraman, C., Zhang, H., Zhang, S., Bellouin, N., Guttikunda, S.K., Hopke, P.K., Jacobson, M.Z., Kaiser, J.W., Klimont, Z., Lohmann, U., Schwarz, J.P., Shindell, D., Storelvmo, T., Warren, S.G. & Zender, C.S. (2013). Bounding the role of black carbon in the climate system: A scientific assessment. J Geophys Res Atmos 118, 1173.CrossRefGoogle Scholar
Egerton, R.F. (2011). Electron Energy-Loss Spectroscopy in the Electron Microscope. New York: Springer.CrossRefGoogle Scholar
Forster, P., Ramaswamy, V., Artaxo, P., Berntsen, T., Betts, R., Fahey, D.W., Haywood, J., Lean, J., Lowe, D.C., Myhre, G., Nganga, J., Prinn, R., Raga, G., Schulz, M. & Van Dorland, R. (2007). Changes in atmospheric constituents and in radiative forcing. In Climate Change 2007: The Physical Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K.B., Tignor, M. & Miller, H.L. (Eds.), pp. 129234. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press.Google Scholar
Gu, L., Srot, V., Sigle, W., Koch, C., van Aken, P., Scholz, F., Thapa, S.B., Kirchner, C., Jetter, M. & Ruhle, M. (2007). Band-gap measurements of direct and indirect semiconductors using monochromated electrons. Phys Rev B 75, 195214.Google Scholar
Hoffer, A., Gelencser, A., Guyon, P., Kiss, G., Schmid, O., Frank, G.P., Artaxo, P. & Andreae, M.O. (2006). Optical properties of humic-like substances (HULIS) in biomass-burning aerosols. Atmos Chem Phys 6, 35633570.CrossRefGoogle Scholar
Johnson, D.W. (1975). Fourier-series method for numerical Kramers-Kronig analysis. J Phys A Math Gen 8(4), 490495.Google Scholar
Johnson, D.W. & Spence, J.C.H. (1974). Determination of single-scattering probability distribution from plural-scattering data. J Phys D Appl Phys 7(6), 771780.Google Scholar
Kirchstetter, T.W., Novakov, T. & Hobbs, P.V. (2004). Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon. J Geophys Res Atmos 109(D21).Google Scholar
Koch, E.E. & Otto, A. (1969). Characteristic energy losses of 30-keV electrons in vapours of aromatic hydrocarbons. Opt Commun 1(2), 4749.Google Scholar
Kroger, E. (1968). Calculations of energy losses of fast electrons in thin foils with retardation. Z Phys 216(2), 115135.Google Scholar
Kroger, E. (1970). Transition radiation, Cerenkov radiation and energy losses of relativistic charged particles traversing thin foils at oblique incidence—Theoretical calculations and numerical computations. Z Phys 235(5), 403421.Google Scholar
Lukacs, H., Gelencser, A., Hammer, S., Puxbaum, H., Pio, C., Legrand, M., Kasper-Giebl, A., Handler, M., Limbeck, A., Simpson, D. & Preunkert, S. (2007). Seasonal trends and possible sources of brown carbon based on 2-year aerosol measurements at six sites in Europe. J Geophys Res Atmos 112(D23).Google Scholar
Moosmuller, H., Chakrabarty, R.K. & Arnott, W.P. (2009). Aerosol light absorption and its measurement: A review. J Quant Spectrosc Ra 110(11), 844878.CrossRefGoogle Scholar
Park, J., Heo, S., Chung, J.G., Kim, H., Lee, H., Kim, K. & Park, G.S. (2009). Bandgap measurement of thin dielectric films using monochromated STEM-EELS. Ultramicroscopy 109(9), 11831188.Google Scholar
Ritchie, R.H. (1957). Plasma losses by fast electrons in thin films. Phys Rev 106(5), 874881.CrossRefGoogle Scholar
Seinfeld, J. (2008). Atmospheric science—Black carbon and brown clouds. Nat Geosci 1(1), 1516.Google Scholar
Stoger-Pollach, M., Franco, H., Schattschneider, P., Lazar, S., Schaffer, B., Grogger, W. & Zandbergen, H.W. (2006). Cerenkov losses: A limit for bandgap determination and Kramers-Kronig analysis. Micron 37(5), 396402.Google Scholar
Zhu, J., Crozier, P.A. & Anderson, J.R. (2012 a). Characterization of light-absorbing carbon particles at three altitudes in East Asian outflow by transmission electron microscopy. Atmos Chem Phys 13, 63596371.CrossRefGoogle Scholar
Zhu, J., Crozier, P.A. & Anderson, J.R. (2012 b). Electron energy-loss spectroscopy of carbonaceous aerosol particles. Microsc Microanal 18(Suppl 2), 17181719.CrossRefGoogle Scholar