Lithium-induced self-assembling of poly(ethylene oxide) intercalated in molybdenum disulfide

Abstract

Static 7Li and 1H NMR experiments were performed between 150 and 400 K. The contributions of both 7Li– 7Li and 7Li– 1H dipolar interactions to the magnetic second moment were determined in the rigid-lattice regime ( T<220 K). Calculated magnetic second moments for different PEO conformations, considering both intra- and inter-molecular interactions, indicate that the polymer in this nanocomposite is compatible with CC bonds predominately in gauche conformations and the oxygen atoms defining tetrahedral sites hosting the lithium ions. The model adequately satisfies the geometric restrictions determined by the structure and the stoichiometry of the product. Furthermore, the temperature dependence of the 7Li linewidth and the 7Li and 1H spin-lattice relaxations for the nanocomposite and two reference compounds, (PEO) 8LiClO 4 and Li 0.22MoS 2, provided information about the effects of PEO intercalation on the polymer and Li + dynamics and conformation, indicating that Li + mobility is coupled to polymer motion, the polymer motion is restricted by the intercalation process, and the chain conformation inside the interlayer space is in the sequence TGGT GG TGG.