Functional nanostructures of montmorillonite with conducting polyaniline

Abstract

The present work describes the effect of montmorillonite (MMT) particles on the alignment of conducting polyaniline (PANI) chains in a PANI/MMT composite. The composite was prepared both as a powder, pressed into pellets, and as thin films deposited on glass surfaces. For comparison, pure PANI was also prepared in these two forms. A combination of X-ray powder diffraction analysis and molecular modelling confirmed the successful intercalation of the PANI into the MMT, while Raman spectroscopy confirmed the presence of the conducting form of PANI (i.e. the emeraldine salt) in all samples. Scanning electron microscopy, transmission electron microscopy and atomic force microscopy were used to study the morphologies of all samples. Conductivity measurements showed that the presence of the MMT particles in the PANI/MMT composites contributes to a significant increase in the electrical conductivity in comparison with the pure PANI samples. Moreover, in the pressed pellets the presence of the MMT particles led to an extremely high electrical anisotropy. The UV-VIS spectroscopy results showed that the PANI/MMT thin film exhibited a selective transmittance in the range 450–650 nm; therefore, the PANI/MMT thin film is not only conductive, but also suitable for use in various optical applications.