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Title: In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry

Abstract

The ability to generate new electrochemically active materials for energy generation and storage with improved properties will likely be derived from an understanding of atomic-scale structure/function relationships during electrochemical events. Here, the design and implementation of a new capillary electrochemical cell designed specifically forin situhigh-energy X-ray diffraction measurements is described. By increasing the amount of electrochemically active material in the X-ray path while implementing low-Zcell materials with anisotropic scattering profiles, an order of magnitude enhancement in diffracted X-ray signal over traditional cell geometries for multiple electrochemically active materials is demonstrated. This signal improvement is crucial for high-energy X-ray diffraction measurements and subsequent Fourier transformation into atomic pair distribution functions for atomic-scale structural analysis. As an example, clear structural changes in LiCoO 2under reductive and oxidative conditions using the capillary cell are demonstrated, which agree with prior studies. Accurate modeling of the LiCoO 2diffraction data using reverse Monte Carlo simulations further verifies accurate background subtraction and strong signal from the electrochemically active material, enabled by the capillary working electrode geometry.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Institute of Standards and Technology (NIST)
OSTI Identifier:
1372235
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Synchrotron Radiation (Online); Journal Volume: 24; Journal Issue: 4
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Young, Matthias J., Bedford, Nicholas M., Jiang, Naisheng, Lin, Deqing, and Dai, Liming. In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry. United States: N. p., 2017. Web. doi:10.1107/S1600577517006282.
Young, Matthias J., Bedford, Nicholas M., Jiang, Naisheng, Lin, Deqing, & Dai, Liming. In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry. United States. doi:10.1107/S1600577517006282.
Young, Matthias J., Bedford, Nicholas M., Jiang, Naisheng, Lin, Deqing, and Dai, Liming. Fri . "In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry". United States. doi:10.1107/S1600577517006282.
@article{osti_1372235,
title = {In situ electrochemical high-energy X-ray diffraction using a capillary working electrode cell geometry},
author = {Young, Matthias J. and Bedford, Nicholas M. and Jiang, Naisheng and Lin, Deqing and Dai, Liming},
abstractNote = {The ability to generate new electrochemically active materials for energy generation and storage with improved properties will likely be derived from an understanding of atomic-scale structure/function relationships during electrochemical events. Here, the design and implementation of a new capillary electrochemical cell designed specifically forin situhigh-energy X-ray diffraction measurements is described. By increasing the amount of electrochemically active material in the X-ray path while implementing low-Zcell materials with anisotropic scattering profiles, an order of magnitude enhancement in diffracted X-ray signal over traditional cell geometries for multiple electrochemically active materials is demonstrated. This signal improvement is crucial for high-energy X-ray diffraction measurements and subsequent Fourier transformation into atomic pair distribution functions for atomic-scale structural analysis. As an example, clear structural changes in LiCoO2under reductive and oxidative conditions using the capillary cell are demonstrated, which agree with prior studies. Accurate modeling of the LiCoO2diffraction data using reverse Monte Carlo simulations further verifies accurate background subtraction and strong signal from the electrochemically active material, enabled by the capillary working electrode geometry.},
doi = {10.1107/S1600577517006282},
journal = {Journal of Synchrotron Radiation (Online)},
number = 4,
volume = 24,
place = {United States},
year = {Fri May 26 00:00:00 EDT 2017},
month = {Fri May 26 00:00:00 EDT 2017}
}
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