Dresden 2006 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
DF: Dielektrische Festkörper
DF 3: Poster Session
DF 3.14: Poster
Montag, 27. März 2006, 09:30–17:00, P1
Effect of anion substitution on Li diffusion in LixTiS2−ySey: Solid state NMR results — •M. Wilkening1, S. Indris1, P. Heitjans1, J. Wontcheu2, W. Bensch2, T. Bredow3, and M. Binnewies4 — 1Hannover University, Institute of Physical Chemistry and Electrochemistry, D-30167Hannover — 2University of Kiel, Institute of Inorganic Chemistry, D-24098 Kiel — 3Hannover University,Theoretical Chemistry, D-30167 Hannover — 4Hannover University, Institute of Inorganic Chemistry, D-30167Hannover
Li intercalated TiS2 is known as a fast two-dimensional ionic conductor. At 298 K the diffusion coefficient DLi turns out to be about 10−14 m2s−1 and the corresponding Li residence time is of the order of 1 µ s. It is of general interest to explore a possible effect of anion substitution on diffusion of small cations. The system LixTiS2−ySey is stable over the whole intercalation range (0 ≤ x ≤ 1) and shows a single-phase structure for all compositions. Due to these properties it represents a singularly well-defined series of materials to investigate whether Li diffusion is influenced by the substitution of selenium anions for sulfur anions having nearly the same ionic radii. Li diffusion in LixTiS2−ySey was studied by means of 7Li solid state NMR. First lineshape analyses of data at a Larmor frequency of 78 MHz and temperatures between 140 K and 450 K indicate, that the Li mobility is slower in, e. g., Li0.7TiSSe than in the pure end member Li0.7TiS2. Supported by the DFG (SPP 1136).