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Measurements of the ¹³C, ⁷Li, and ¹H nuclear magnetic resonance (NMR) of the nanocomposite formed by the intercalation of lithium and diethylamine in molybdenum disulfide, Li0.1MoS2[(C2H5)2NH]0.2, are reported. The strong Li−Li dipolar interaction strength, calculated from the ⁷Li NMR decoupling data, suggests the formation of lithium clusters. The dimensional restriction of the available space between the host layers supports a hypothesis that is based on the formation of Li3 clusters stabilized by amine ligands. The lithium relaxation is mainly due to the interaction between the quadrupolar moment of the ⁷Li nuclei and the fluctuating electric field gradient at the site of the nucleus, produced by the surrounding charge distribution. The dynamical parameters obtained from the ⁷Li temperature dependence of the spin−lattice relaxation indicate a high lithium mobility, which is attributed to the fast exchange motion of the lithium ions between the coordination sites within each Li3 aggregate. The ¹H line shape and relaxation data support the proposed structural model for the lithium−diethylamine cluster. Numerical analysis of the ¹H line shape indicates that the intercluster dipole−dipole interactions are responsible for most of the spectral broadening. ¹H spin−lattice relaxation is mainly governed by hydrogen nuclei in the less-mobile CH2 and in the fast-relaxing CH3 groups in the diethylamine molecule.

Measurements of 1 H and 7 Li Nuclear Magnetic Resonance (NMR) are reported for the nanocomposite formed by the intercalation of lithium and dibutylamine in molybdenum disulfide, Li 0.1 [(C 4 H 9 ) 2 NH] y MoS 2 . The temperature dependence NMR lineshapes and spin-lattice relaxation times ( T l ) measured exhibit the qualitative features associated with the lithium motions, namely the presence of a line narrowing at 230 K. The 1 H and the 7 Li longitudinal magnetization recovery was found to be non exponential. The T l values at each temperature was determined from the fit of a stretched exponential function. An activation energy for the lithium motion E a ≈0.18 eV was extracted from the 7 Li relaxation data. The dynamical parameters obtained from the 7 Li temperature dependence relaxation data indicate the mobility of the lithium in the nanocompositeis of the same order of magnitude as those obtained in other lithium intercalation compounds.

In this work we report a proton ( 1 H) and lithium ( 7 Li) NMR lineshape and spin-lattice relaxation time investigation of this polymer electrolyte obtained from the polymerization of ethylene glycol and citric acid with lithium salt. The 7 Li data indicates that the lineshape and spin-lattice relaxation is affected by the coupling of its quadrupolar moment to the surrounding electric field gradients. The activation energy for the lithium motion extracted from the 7 Li relaxation data is 0.23 eV. The dynamics parameters obtained from the NMR data indicate that the lithium mobility in the EG:CA:LiClO 4 is comparable to those found in polymer gel electrolytes and in plasticized polymer electrolytes.