Electrical transport properties of conjugated polymer onto self-assembled aligned carbon nanotubes

We present a simple fabrication method for a micrometer-scale conducting network made of self-assembled aligned carbon nanotubes (CNTs) thin films deposited by pulsed plasma enhanced chemical vapour deposition technique. Once the nanotubes have been grown, spin coating has been used to prepare a CNTs/conjugated polymer composite. The electrical transport properties of the hybrid system formed by the conjugated polymer (poly(3-octylthiophene)-P3OT) and CNTs have been then characterised without any further processing. At room temperature the aligned nanotubes show an ohmic behaviour, while the current-voltage characteristic curve indicates a surface potential modification of the system CNTs/conjugated polymer leading to a semiconductor behaviour. Raman spectroscopy is successfully applied to demonstrate that in the composite film the changes in the electrical resistance can be explained in terms of intercalation of the polymer matrix and interaction of P3OT with the nanotubes. (C) 2003 Elsevier Science B.V. All rights reserved. RI Valentini, Luca/D-5238-2011; Kenny, Jose/F-9372-2010