Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-24T05:34:57.309Z Has data issue: false hasContentIssue false

Quantitative Energy-Dispersive X-Ray Analysis of Catalyst Nanoparticles Using a Partial Cross Section Approach

Published online by Cambridge University Press:  12 January 2016

Katherine E. MacArthur*
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
Thomas J. A. Slater
Affiliation:
Materials Science Centre, University of Manchester, Manchester M13 9PL, UK
Sarah J. Haigh
Affiliation:
Materials Science Centre, University of Manchester, Manchester M13 9PL, UK
Dogan Ozkaya
Affiliation:
Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading RG4 9NH, Reading, UK
Peter D. Nellist
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
Sergio Lozano-Perez
Affiliation:
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
*
*Corresponding author.[email protected]
Get access

Abstract

The new generation of energy-dispersive X-ray (EDX) detectors with higher count rates than ever before, paves the way for a new approach to quantitative elemental analysis in the scanning transmission electron microscope. Here we demonstrate a method of calculating partial cross sections for use in quantifying EDX data, beneficial especially because of the simplicity of its implementation. Applying this approach to acid-leached PtCo catalyst nanoparticles leads to quantitative determination of the Pt surface enrichment.

Type
Materials Applications
Copyright
© Microscopy Society of America 2016 

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

Allen, L.J., D’Alfonso, A.J., Freitag, B. & Klenov, D.O. (2012). Chemical mapping at atomic resolution using energy-dispersive X-ray spectroscopy. MRS Bull 37, 4752.CrossRefGoogle Scholar
Batson, P.E., Dellby, N. & Krivanek, O.L. (2002). Sub-Ångstrom resolution using aberration corrected electron optics. Nature 418, 617620.CrossRefGoogle ScholarPubMed
Cliff, G. & Lorimer, G.W. (1975). The quantitative analysis of thin specimens. J Microsc 103, 203207.CrossRefGoogle Scholar
E., H., MacArthur, K.E., Pennycook, T.J., Okunishi, E., D’Alfonso, A.J., Lugg, N.R., Allen, L.J. & Nellist, P.D. (2013). Probe integrated scattering cross sections in the analysis of atomic resolution HAADF STEM images. Ultramicroscopy 133, 109119.CrossRefGoogle ScholarPubMed
Egerton, R.F. (2011). Electron Energy Loss Spectroscopy in the Electron Microscope, 3rd ed. New York: Springer.CrossRefGoogle Scholar
Genc, A., Kovarik, L., Gu, M., Cheng, H., Plachinda, P., Pullan, L., Freitag, B. & Wang, C. (2013). XEDS STEM tomography for 3D chemical characterization of nanoscale particles. Ultramicroscopy 131, 2432.CrossRefGoogle ScholarPubMed
Goldstein, J.I., Costley, J.L., Lorimer, G.W. & Reed, R.J.B. (1977). Quantitative X-ray analysis in the electron microscope. In Scanning Electron Microscopy, vol. 1, Johari, O (Ed.), pp. 315–324. Chicago: IIT Research Institute.Google Scholar
Goldstein, J., Newbury, D.E., Joy, D.C., Lyman, C.E., Echlin, P., Lifshin, E., Sawyer, L. & Michael, J.R. (2003). Scanning Electron Microscopy and X-Ray Microanalysis, 3rd ed. New York, USA: Springer US.CrossRefGoogle Scholar
Hofer, F. (1991). Determination of inner-shell cross sections for EELS-quantification. Microsc Microanal Microstruct 2, 215230.CrossRefGoogle Scholar
Iakoubovskii, K., Mitsuishi, K., Nakayama, Y. & Furuya, K. (2008). Thickness measurements with electron energy loss spectroscopy. Microsc Res Tech 71, 626631.CrossRefGoogle ScholarPubMed
Itakura, M., Watanabe, N., Nishida, M., Daio, T. & Matsumura, S. (2013). Atomic-resolution X-ray energy-dispersive spectroscopy chemical mapping of substitutional Dy atoms in a high-coercivity neodymium magnet. Jpn J Appl Phys 52, 050201.CrossRefGoogle Scholar
Jones, L., MacArthur, K.E., Fauske, V.T., van Helvoort, A.T.J. & Nellist, P.D. (2014). Rapid estimation of catalyst nanoparticle morphology and atomic-coordination by high-resolution z-contrast electron microscopy. Nano Lett 14, 63366341.CrossRefGoogle ScholarPubMed
Kothleitner, G., Neish, M.J., Lugg, N.R., Findlay, S.D., Grogger, W., Hofer, F. & Allen, L.J. (2014). Quantitative elemental mapping at atomic resolution using X-ray spectroscopy. Phys Rev Lett 112, 085501.CrossRefGoogle Scholar
Kotula, P.G., Klenov, D.O. & Von Harrach, H.S. (2012). Challenges to quantitative multivariate statistical analysis of atomic-resolution X-ray spectral. Microsc Microanal 18, 691698.CrossRefGoogle Scholar
Krivanek, O.L., Dellby, N., Spence, A.J., Camps, R.A. & Brown, L.M. (1997). Aberration correction in the STEM. Electron Microsc Anal 153, 3540.Google Scholar
Lechner, P., Fiorini, C., Hartmann, R., Kemmer, J., Krause, N., Leutenegger, P., Longoni, A., Soltau, H., Stotter, D., Stotter, R., Struder, L. & Weber, U. (2001). Silicon drift detectors for high count rate X-ray spectroscopy at room temperature. Nucl Instrum Methods Phys Res A 458, 281287.CrossRefGoogle Scholar
Liu, Z., Ma, L., Zhang, J.Y., Hongsirikarn, K. & Goodwin, J.G. (2013). Pt alloy electrocatalysts for proton exchange membrane fuel cells: A review. Catal Rev 55, 255288.CrossRefGoogle Scholar
Lugg, N.R., Kothleitner, G., Shibata, N. & Ikuhara, Y. (2014). On the quantitativeness of EDS STEM. Ultramicroscopy 151, 150159.CrossRefGoogle ScholarPubMed
MacArthur, K.E., Alfonso, A.J.D., Ozkaya, D., Allen, L.J. & Nellist, P.D. (2015). Optimal ADF STEM imaging parameters for tilt-robust image quantification. Ultramicroscopy 156, 18.CrossRefGoogle ScholarPubMed
Maher, D.M., Joy, D.C., Ellington, M.B., Zaluzec, N.J. & Mochel, P.E. (1981). Relative accuracy of k-factor calculations for thin-film X-ray analysis. In Analytical Electron Microscopy, Geiss, R.H. (Ed.), pp. 33--38. San Francisco: San Francisco Press.Google Scholar
Malis, T., Cheng, S.C. & Egerton, R.F. (1988). EELS log-ratio technique for specimen-thickness measurement in the TEM. J Electron Microsc Tech 8, 193200.CrossRefGoogle ScholarPubMed
Meltzman, H., Kauffmann, Y., Thangadurai, P., Drozdov, M., Baram, M., Brandon, D. & Kaplan, W.D. (2009). An experimental method for calibration of the plasmon mean free path. J Microsc 236, 165173.CrossRefGoogle ScholarPubMed
Newbury, D.E., Williams, D.B., Goldstein, J.I. & Fiori, C.E. (1984). Observations on the calculation of kAB factors for analytical electron microscopy. Anal Electron Microsc 2, 276278.Google Scholar
Ni, N., Lozano-Perez, S., Sykes, J. & Grovenor, C. (2011). Quantitative EELS analysis of zirconium alloy metal/oxide interfaces. Ultramicroscopy 111, 123130.CrossRefGoogle ScholarPubMed
Phillips, P.J., Paulauskas, T., Rowlands, N., Nicholls, A.W., Low, K.-B., Bhadare, S. & Klie, R.F. (2014). A new silicon drift detector for high spatial resolution STEM-XEDS: Performance and applications. Microsc Microanal 20, 10461052.CrossRefGoogle ScholarPubMed
Retsky, M. (1974). Observed single atom elastic cross sections in a scanning electron microscope. Optik 41, 127142.Google Scholar
Rosenauer, A., Mehrtens, T., Müller, K., Gries, K., Schowalter, M., Satyam, P.V., Bley, S., Tessarek, C., Hommel, D., Sebald, K., Seyfried, M., Gutowski, J., Avramescu, A., Engl, K. & Lutgen, S. (2011). Composition mapping in InGaN by scanning transmission electron microscopy. Ultramicroscopy 111, 13161327.CrossRefGoogle ScholarPubMed
Skiff, W.M., Carpenter, R.W., Lin, S.H. & Higgs, A. (1988). K, L, M, N, O and P ionziation cross sections for electron energy loss spectroscopy. Ultramicroscopy 25, 4760.CrossRefGoogle Scholar
Slater, T.J.A., Camargo, P.H.C., Burke, M.G., Zaluzec, N.J. & Haigh, S.J. (2014 a). Understanding the limitations of the Super-X energy dispersive X-ray spectrometer as a function of specimen tilt angle for tomographic data acquisition in the S/TEM. J Phys Conf Ser 522, 012025.CrossRefGoogle Scholar
Slater, T.J.A., Macedo, A., Schroeder, S.L.M., Burke, M.G., O’Brien, P., Camargo, P.H.C. & Haigh, S.J. (2014 b). Correlating catalytic activity of Ag-Au nanoparticles with 3D compositional variations. Nano Lett 14, 19211926.CrossRefGoogle ScholarPubMed
Strasser, P., Koh, S., Anniyev, T., Greeley, J., More, K., Yu, C., Liu, Z., Kaya, S., Nordlund, D., Ogasawara, H., Toney, M.F. & Nilsson, A. (2010). Lattice-strain control of the activity in dealloyed core-shell fuel cell catalysts. Nat Chem 2, 454460.CrossRefGoogle ScholarPubMed
Watanabe, M., Ackland, D.W., Kiely, C.J., Williams, D.B., Kanno, M., Hynes, R. & Sawada, H. (2006). The aberration corrected JEOL JEM-2200FS FEG-STEM/TEM fitted with an Ω electron energy-filter: Performance characterization and selected applications. JEOL News 41, 27.Google Scholar
Watanabe, M., Horita, Z. & Nemoto, M. (1996). Absorption correction and thickness determination using the zeta factor in quantitative X-ray microanalysis. Ultramicroscopy 65, 187198.CrossRefGoogle Scholar
Watanabe, M. & Williams, D.B. (2006). The quantitative analysis of thin specimens: A review of progress from the Cliff-Lorimer to the new zeta-factor methods. J Microsc 221, 89109.CrossRefGoogle Scholar
Watanabe, M., Williams, D.B. & Tomokiyo, Y. (2003). Comparison of detectability limits for elemental mapping by EF-TEM and STEM-XEDS. Micron 34, 173183.CrossRefGoogle ScholarPubMed
Zaluzec, N.J. (2013). Direct comparison of X-ray detector solid angles in analytical electron microscopes. Microsc Microanal 19, 12621263.CrossRefGoogle Scholar
Zaluzec, N.J. (2014). Analytical formulae for calculation of X-ray detector solid angles in the scanning and scanning/transmission analytical electron microscope. Microsc Microanal 20, 13181326.CrossRefGoogle ScholarPubMed