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Title: Revealing local order via high energy EELS
Short range order (SRO) is critical in determining the performance of many important engineering materials. However, accurate characterization of SRO with high spatial resolution – which is needed for the study of individual nanoparticles and at material defects and interfaces – is often experimentally inaccessible. Here, we locally quantify SRO via scanning transmission electron microscopy with extended energy loss fine structure analysis. Specifically, we use novel instrumentation to perform electron energy loss spectroscopy out to 12 keV, accessing energies which are conventionally only possible using a synchrotron. Our data is of sufficient energy resolution and signal-to-noise ratio to perform quantitative extended fine structure analysis, which allows determination of local coordination environments. To showcase this technique, we investigate a multicomponent metallic glass nanolaminate and locally quantify the SRO with <10 nm spatial resolution; this measurement would have been impossible with conventional synchrotron or electron microscopy methods. We discuss the nature of SRO within the metallic glass phase, as well as the wider applicability of our approach for determining processing–SRO–property relationships in complex materials.  more » « less
Award ID(s):
1910066
NSF-PAR ID:
10496932
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Elsevier - Materials Today Nano
Date Published:
Journal Name:
Materials Today Nano
Volume:
21
Issue:
C
ISSN:
2588-8420
Page Range / eLocation ID:
100298
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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