Orientation of carbon nanotubes (CNT) in semiconducting polymer hosts using electric fields for optoelectronic applications

Carbon nanotubes (CNTs) are good candidates for electronic and optoelectronic devices because of their unique physical properties [1, 2]. CNT coupling or combination with semi-conducting polymer hosts is a promising strategy to demonstrate cheap functional nanocomposites in printed electronics or optoelectronics fields [3, 4]. Meanwhile the difficulty to finely control their dispersion is a strong limitation to their development. In this work, we report on the controlled structuration of blends of CNT with the poly-(3-hexylthiophene) (P3HT) conjugated polymer, to demonstrate organic nanocomposites presenting improved and tunable electrical properties. First, we present a study on the influence of the main parameters controlling the CNT dispersion and orientation on planar devices or in the polymer host matrix using a simple drop-casting procedure under applied electric field. Used planar inter-digited electrode geometries allows both morphological, spectroscopic, and electrical characterizations, as a function of the experimental conditions used (concentration, nature of the solvent, applied electric field characteristics,etc.). Finally, the resulting field-effect transistor geometry enables the charge transport properties characterization for the obtained nanocomposites as a function of CNT loading and dispersion