Atomic Layer Fluorination of Li4Ti5O12 Surface: a multi-probing survey.

Li4Ti5O12 (LTO) particles are successfully modified by an atomic layer fluorination process using a one-shot solvent-free synthesis performed with a solid-state fluorinating agent, xenon difluoride, at room temperature. LTO is reported as a promising anode material for lithium-ion batteries (LIB) where high charging rates and long cycle life are required, because of its high potential preventing lithium dendrites deposition. The fluorination leads to the formation of passivating LiF environments at the particles surface using the lowest amount of fluorine reported in the literature. Thanks to a multi-probing strategy, the impact of the fluorination on non-modified, non-coated, LTO has been characterized from the bulk to the extreme surface. The XRD patterns as well as the Raman spectra show no structural modification of the bulk while the combination of the XPS and NMR analysis give insights about the impact of the fluorination on the entirety of the material. Auger fluorine chemical mapping displays the ...