Syntheses and characterizations of polymer/TaS 2 layered nanocomposites

Polymer/TaS2 layered nanocomposites have been synthesized by using the exfoliation-adsorption technique. Single crystals of layered transition-metal dichalcogenides of 1T-TaS2, 2H-TaS2, and 4Hb-TaS2 were used as host materials. Poly(ethylene oxide) (PEO) and poly(ethylenimine) (PEI) were adopted as guest intercalants. As the exfoliation-adsorption method may require complicated procedures, optimum conditions to synthesize nanocomposites were estimated for each set of TaS2 polytypes and polymers. They have been characterized by powder X-ray diffraction (XRD) and electrical dc resistivity measurements. XRD patterns showed that all samples of the polymer/TaS2 layered nanocomposites contain organic polymer between all individual TaS2 sheets. Although 1T-, 2H-, and 4Hb-TaS2 polytypes are well known to show quite different temperature dependences of resistivity, the resistivities of all nanocomposites show similar temperature dependences.