In situ polymerization and characterizations of polyaniline on MWCNT powders and aligned MWCNT films

Polyaniline/CNT composites have been synthesized by means of in situ polymerization on two different macroscopic structures of CNTs, namely non-ordered CNT powders and aligned CNT films supported on Ti foils. SEM, TEM images illustrated that a rather uniform layer of PANI with a thickness of 5-8 nm has been successfully coated on the aligned CNTs. The molecular structure and the degree of protonation of PANI have been studied by means of Raman spectroscopy. The alignment of CNT film on the foils favors the formation of uniformly distributed layer of the protonated PANI on each CNT, which is possibly a result of controlled diffusion in the pseudo 1 D channel and a confinement in the space between CNTs in the aligned CNT films. Furthermore, the reaction temperature has a more pronounced effect on the degree of protonation of PANI on the CNT powders than on the aligned CNT films. (C) 2009 Elsevier B.V. All rights reserved.