Mechanistic insights of Li+ diffusion within doped LiFePO4 from Muon spectroscopy

Johnson, I. D., Ashton, T. E., Blagovidova, E., Smales, G. J., Lübke, M., Baker, P. J., Corr, S. A. and Darr, J. A. (2018) Mechanistic insights of Li+ diffusion within doped LiFePO4 from Muon spectroscopy. Scientific Reports, 8, 4114. (doi: 10.1038/s41598-018-22435-1) (PMID:29515155) (PMCID:PMC5841297)

Abstract

The Li+ ion diffusion characteristics of V- and Nb-doped LiFePO4 were examined with respect to undoped LiFePO4 using muon spectroscopy (µSR) as a local probe. As little difference in diffusion coefficient between the pure and doped samples was observed, offering DLi values in the range 1.8–2.3 × 10−10 cm2 s−1, this implied the improvement in electrochemical performance observed within doped LiFePO4 was not a result of increased local Li+ diffusion. This unexpected observation was made possible with the µSR technique, which can measure Li+ self-diffusion within LiFePO4, and therefore negated the effect of the LiFePO4 two-phase delithiation mechanism, which has previously prevented accurate Li+ diffusion comparison between the doped and undoped materials. Therefore, the authors suggest that µSR is an excellent technique for analysing materials on a local scale to elucidate the effects of dopants on solid-state diffusion behaviour.

• Item Type: Articles
• Additional Information: JAD would like to thank the EPSRC for funding (EP/R023662/1; Te JUICED Hub [Joint University Industry Consortium for Energy (Materials) and Devices Hub]). EPSRC are thanked by JAD, TEA, EB and ML for funding the ELEVATE project (EP/M009394/1) and by IDJ for funding the Centre for Doctoral Training in Molecular Modelling & Materials Science (EP/G036675/1, UCL, U.K.) which supports a studentship for IDJ. A Star (Singapore) is thanked for supporting a studentship for ML.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Corr, Professor Serena
• Authors: Johnson, I. D., Ashton, T. E., Blagovidova, E., Smales, G. J., Lübke, M., Baker, P. J., Corr, S. A., and Darr, J. A.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Scientific Reports
• Publisher: Nature Research
• ISSN: 2045-2322
• ISSN (Online): 2045-2322
• Copyright Holders: Copyright © 2018 The Authors
• First Published: First published in Scientific Reports 8: 4114
• Publisher Policy: Reproduced under a Creative Commons License