MSA  Vol.9 No.6 , May 2018
Structure Refinement of Mn-Substituted LiMnxFe1-xPO4
Abstract: For Mn substituted LiMnxFe1-xPO4 synthesized by hydrothermal process, the structural differences caused by Mn substitution were characterized by SEM, ICP, XRD, XAFS, and FT-IR. In this study, by using XAFS advantageous to the atomic selectivity, the local structure of MeO6 octahedral was investigated. From ICP, Mn composition in the products was similar to Mn addition amount, and the peak shifts of XRD patterns with increasing Mn addition were observed. The lattice constants refined by Rietveld analysis were a = 1.0338 ± 5 nm, b = 0.5995 ± 4 nm and c = 0.4696 ± 1 nm in LiFePO4, and it was expanded linearly with increasing Mn addition. Fe-O bond distance, which was calculated by curve fitting of the radius distribution function of LiMnxFe1-xPO4, was 0.208 nm smaller than 0.214 nm of Mn-O bond. In addition, MeO6 octahedral expansion was affected to PO4 vibrational structure from FT-IR spectra.
Cite this paper: Togo, M. and Nakahira, A. (2018) Structure Refinement of Mn-Substituted LiMnxFe1-xPO4. Materials Sciences and Applications, 9, 542-553. doi: 10.4236/msa.2018.96039.

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