| The intercalation of oligomers or polymers into layered tungsten disulfide with good semiconductor properties can induce novel electrical, structural, and mechanical properties. Such systems may exhibit hybrid properties synergistically derived from both the host and the guest, which makes them potentially applied in fields such as cathode materials and antifriction materials. In this thesis, lithium intercalated tungsten disulfide LixWS2 was prepared through the solvothermal synthesis technique. The layered nanocomposites PEG/WS2, PEO/WS2, intercalating poly(ethylene glycol) (PEG, mw≈1×103, 6×103, 1×104) and poly(ethylene oxide) (PEO, mw≈3×105) into the tungsten disulfide host galleries, were prepared using the exfoliated-restacked technique. The layered nanocomposite polypyrrole/WS2 was prepared via the combination of the exfoliated-restacked technique and in situ oxidative polymerization. The structures, morphologies and properties of the composites were studied by means of XRD, DSC, TGA, IR, SEM, a conventional four-probe method ect.Firstly, a set of LixWS2 were prepared at varios temperature, and the Li concentration x in LixWS2 increases as the intercalation temperature increase, and saturates at about 1.3 when the intercalation temperature reaches 100°C. Unstable in air as it is, the fresh prepared Li1.3WS2 could remained unchanged under vacuum (about 4 kPa) for 5 days. Single-molecule-layer suspension of tungsten disulfide was obtained through the reaction of Li1.3WS2 and water. The pH dependences of surfaceζpotential for single molecular layers of WS2 were determined, illustrating that its isoeletric point is approximately at pH = 3.Secondly,it was revealed that the intercalated PEG or PEO within the host galleries are in a double-layer arrangement with an interlayer expansion of about 0.9 nm. Thermal analyses suggested that the resulting material shows good thermal stability, with the decomposition of the interacted Polyethylether chains within the disulfide galleries occurring at around 258°C. Despite high conductivity of the host material, those of the PEG, PEO/WS2 nanocomposites were found to be high in the order of 1×10-2～10-3 S cm-1 at ambient temperature, resulted from the host guest-host charge transfers.Thirdly, the intercalation of PPy into the host galleries results in an interlayer expansion of about 0.37 nm, which is consistent with having a monolayer of the polymer chain lying parallel with respect to the WS2. Thermal analyses suggested that the resulting material shows good thermal stability, with the decomposition of the interacted polymeric chains within the disulfide galleries occurring at around 400°C. The electrical conductivity of PPy/WS2 nanocomposite was found to be high in the order of 1×10-2 S cm-1 at ambient temperature.
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