| The exfoliation-encapsulative precipitation (EEP) method, which was introduced by Kanatzidis and Bissessur in 1993, is both convenient and general. It enables the formation of an intercalated polymer-layered inorganic nanocomposite when a polymer solution and an inorganic monolayer suspension are mixed. Many MoS 2/polymer nanocomposites were synthesized.; In this dissertation, we expand the investigation of the MoS2 system, contribute a better understanding and provide a better manipulation of the reactions. Moreover, we further develop the EEP method by extending its application to other layered materials such as TaS2, MoO 3, α-RuCl3 and WS2, and by modifying the method so that the intercalation of intractable polymers such as polypyrrole is possible.; In the research, it was found that “LiMoS2” would not be oxidized completely to MoS2 upon exposure to water or air, and the exfoliation of “LiMoS2” in water is a process of solvation of Lix(H2O)yMoS2 (x ∼ 0.18). Like Ax(H2O)yTiS2 (A = Li, Na, K), Lix(H2O)yMoS2 can be exfoliated by stirring. Additional polymers such as polyacrylamide, polyvinylalcohol, polypropylene, polystyrene, polymethylmethacrylate, polybenzimidazole, polyethyleneterephthalate and polypyrrole were encapsulated in MoS2. A convenient method to prepare “LiMoS2” was developed, which uses LiBH4 as a reagent and runs at elevated temperatures (300–350°C). This method can also be used to lithiate other layered transition metal dichalcogenides.; The lithium intercalated materials exfoliate well and encapsulate polymers better than the sodium intercalated materials, at least in the systems of 2H-TaS2 and MoO3. At room temperature, LiBH4 was proven a good lithiation reagent for 2H-TaS2. MoO3 and α-RuCl3. The amount of LiBH4 used in the reaction is crucial to the exfoliation and encapsulation properties of the products. Water-soluble polymers such as poly(ethylene oxide) (PEO) and polyvinylpyrrolidone were intercalated in all three layered materials and polypyrrole was intercalated in RuCl3.; In addition, α-RuCl3/polyaniline nanocomposites, were prepared by the in situ redox intercalative polymerization method, which up to now was only applicable to FeOCl, V2O 5 and VOPO4. The reaction is driven by the reduction of some of the Ru3+ centers to Ru2+ and completed by the participation of ambient oxygen as an electron acceptor.; The large variety of new polymer-nanocomposites thus prepared have many interesting physical properties. For example, TaS2 nanocomposites are superconductors at low temperatures; RuCl3 nanocomposites have adjustable magnetic properties. The arrangement of PEO chains in the interlayer galleries was explored and we believe that MoS2/PEO, TaS2 /PEO and RuCl3/PEO nanocomposites contain in each gallery two sheets of PEO chains in the type-II PEO-HgCl2 complex conformation. The two sheets of PEO chains are believed to have -O- atoms facing each other at the center of the gallery and provide Li+ ions a good two-dimensional migration channel. |
