Identifying and imaging polymer functionality at high spatial resolution with core-loss EELS.

Autor: Colby R; Research, ExxonMobil Technology and Engineering Company, USA. Electronic address: robert.j.colby@exxonmobil.com., Williams REA; Center for Electron Microscopy and Analysis, The Ohio State University, USA., Carpenter DL 3rd; Research, ExxonMobil Technology and Engineering Company, USA., Bagués N; Department of Materials Science and Engineering, The Ohio State University, USA; Center for Electron Microscopy and Analysis, The Ohio State University, USA., Ford BR; Department of Materials Science and Engineering, The Ohio State University, USA., McComb DW; Department of Materials Science and Engineering, The Ohio State University, USA; Center for Electron Microscopy and Analysis, The Ohio State University, USA.
Jazyk: angličtina
Zdroj: Ultramicroscopy [Ultramicroscopy] 2023 Apr; Vol. 246, pp. 113688. Date of Electronic Publication: 2023 Jan 18.
DOI: 10.1016/j.ultramic.2023.113688
Abstrakt: Electron energy loss spectroscopy (EELS) is a proven tool for probing materials chemistry at high spatial resolution. Core-loss EELS fine structure should allow measurement of local polymer chemistry. For organic materials, sensitivity to radiolysis is expected to limit the resolution achievable with EELS: but core-loss EELS has proven difficult at any resolution, yielding inconsistent spectra that compare unfavorably with theoretically analogous x-ray absorption spectra. Many of the previously identified shortcomings should not be limiting factors on modern equipment. This study establishes that EELS can generate identifiable carbon K-edge spectra for a range of common polymer types and chemistry, and demonstrates fine structure features matching prior x-ray absorption spectra. EELS fine structure features broaden intuitively with the instrument's energy resolution, and beam-induced features are readily differentiated by collecting spectra at a series of doses. The results are demonstrated with spectrum images of a model polymer blend, and used to estimate practical pixel sizes that can be used for mapping core-loss EELS as a function of electron dose.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023. Published by Elsevier B.V.)
Databáze: MEDLINE
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