X-RAY SPECTROSCOPY STUDY OF LITHIATED GRAPHITE OBTAINED BY THERMAL DEPOSITION OF LITHIUM
L.L. Lapteva1,2, Yu.V. Fedoseeva1,2, P.N. Gevko1, D.A. Smirnov3, A.V. Gusel’nikov1, L.G. Bulusheva1,2, A.V. Okotrub1,2
1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
2Novosibirsk National Research State University, Novosibirsk, Russia
3Institute of Solid State Physics, Dresden, Germany
Keywords: природный графит, литирование, термическое напыление, рентгеновская эмиссионная спектроскопия, ближняя тонкая структура рентгеновского поглощения, рентгеновская фотоэлектронная спектроскопия, квантово-химическое моделирование, natural graphite, lithiation, thermal deposition, X-ray emission spectroscopy, near edge X-ray absorption fine structure, X-ray photoelectron spectroscopy, quantum chemical simulation
Abstract
X-ray photoelectron spectroscopy (XPS), X-ray emission spectroscopy (XES), and near edge X-ray absorption fine structure (NEXAFS) spectroscopy are used for in situ studies of the electronic structure of lithiated natural graphite produced by thermal deposition of lithium upon graphite in a vacuum. By XPS and NEXAFS spectroscopy it is found that lithium vapor thermal deposition results in the formation of a lithiated graphite surface layer and a change in its electronic structure. Based on the quantum chemical simulation of the experimental СKα XES spectrum of lithiated graphite, it is found that lithium atoms are located mostly on the edges of graphite crystallites. Atomic force microscopy reveals that the size of natural graphite flakes varies from 50 nm to 200 nm.
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