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arXiv · 1902.03318

Reciprocal Space Imaging of Ionic Correlations in Intercalation Compounds

Matthew J. Krogstad·Stephan Rosenkranz·Justin M. Wozniak·Guy Jennings·Jacob P. C. Ruff·John T. Vaughey·Raymond Osborn
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Abstract

The intercalation of alkali ions into layered materials has played an essential role in battery technology since the development of the first lithium-ion electrodes. Coulomb repulsion between the intercalants leads to ordering of the intercalant sublattice, which hinders ionic diffusion and impacts battery performance. While conventional diffraction can identify the long-range order that can occur at discrete intercalant concentrations during the charging cycle, it cannot determine short-range order at other concentrations that also disrupt ionic mobility. In this article, we show that the use of real-space transforms of single crystal diffuse scattering, measured with high-energy synchrotron x-rays, allows a model-independent measurement of the temperature dependence of the length scale of ionic correlations along each of the crystallographic axes in a sodium-intercalated V$_2$O$_5$. The techniques described here provide a new way of probing the evolution of structural ordering in crystalline materials.

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Matthew J. Krogstad, Stephan Rosenkranz, Justin M. Wozniak, Guy Jennings, Jacob P. C. Ruff, John T. Vaughey, Raymond Osborn. 2019-02-08. Reciprocal Space Imaging of Ionic Correlations in Intercalation Compounds. https://doi.org/10.1038/s41563-019-0545-7

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