Self-assembled Films of Poly(o-Ethoxyaniline) Grafted with Functionalized Multiwalled Carbon Nanotubes

Abstract

In this study, composites based on poly(o-ethoxyaniline), POEA, and its composites grafted with functionalized multiwalled carbon nanotubes (MWCNT) were obtained by the oxidative in situ chemical polymerization varying the mass ratio of o-ethoxyaniline:MWCNT of 100:1 and 100:5. POEA and its POEA-MWCNT grafted composites were used to prepare self-assembled (SA) deposited onto indium tin oxide (ITO) substrates with alternating layers of polystyrene sulfonate (PSS). The structure and morphology of the samples were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The SA films were characterized by cyclic voltammetry, UV–Vis and electrochemical impedance spectroscopy (EIS). The EIS results showed expressive decrease of the polarization resistance (Rp), from 13,342 Ω, for POEA/PSS, to 568 Ω for POEA-MWCNT(100:1)/PSS (about 23 times lower) and to 240 Ω for POEA-MWCNT(100:5)/PSS film. Considering that higher mass proportions of MWCNT can affect the final morphology and the oxidation ratio of POEA chains and aiming strong interactions between the POEA and MWCNT as well the significant reduction of charge transfer resistance, the SA film POEA-MWCNT(100:1)/PSS has potential for future applications as sensors and charge storage devices.