Spectroscopic study of poly(ethylene oxide)6: LiX complexes (X = PF6, AsF6, SbF6, ClO4)

Sol–gel preparation of a di-ureasil electrolyte doped with lithium perchlorate

“…This anion has a tetrahedral symmetry and the nine vibrational degrees freedoms are distributed into four normal modes: Upon coordination, the ν 1 (A 1 ) band was found to shift to higher wavenumbers [23][24][25][26][27][28][29][30].…”

Li Intercalation into Graphite: Direct Optical Imaging and Cahn–Hilliard Reaction Dynamics

“…The peaks below G peak are from PEO and P(EO)-Li complexes. 4 Stage 1 intercalation compound was achieved with external applied voltage at -5V.…”

“…[11][12][13] As a result of these and other complications 27 , reported values of the Li diffusion coefficient inside graphite vary by about 10 orders of magnitude, from 10 -6 to 10 -16 cm 2 /s. 4,14 We report direct all-optical reflectance imaging of Li intercalation kinetics into a lithographically defined, single crystal of bulk graphite. Classical diffusion models fail to capture the propagating phase fronts and concentration profiles, but we show, for the first time, that the recently developed Cahn-Hillard reaction (CHR) theory of non-equilibrium phase separating systems 24,26 can quantitatively describe our observations, using a periodic two-layer free energy model 27 with novel generalized Butler-Volmer kinetics.…”

“…1 Lithium intercalated graphite shows a rich phase diagram and is widely used as the anode in batteries and other electrochemical energy storage systems. Understanding Li intercalation is a critical technological problem that has been studied principally using electrochemical methods: [2][3][4][5][6][7][8] potentiostatic intermittent titration (PITT), galvanostatic intermittent titration (GITT), electrochemical impedance spectroscopy (EIS), and slow scan rate cyclic voltammetry(CV). Additional information on elementary atomic hopping steps of Li transport has also been obtained from nuclear magnetic resonance.…”

Correction to Vibrational Study of the Crystalline Phases of (CH3(OCH2CH2)2OCH3)2LiSbF6 and P(EO)6LiMF6 (M = P, As, Sb)

“…1 While this article was in proof, Prof. J.-C. Lasségues and co-workers published a similar study. 2 Prof. Lasségues kindly called my (R. Frech's) attention to the fact that our Raman data for the P(EO) 6 AsF 6 compound were consistently higher than their data by about 4-5 wavenumbers, although the data for the other two compounds were in very good agreement. In an effort to resolve this difference, we repeated the sample preparation and Raman measurements twice.…”