Poly(vinyl alcohol)-assisted dispersion of multiwalled carbon nanotubes in aqueous solution for electroanalysis

Multiwalled carbon nanotubes (MWNTs) were directly dispersed into poly(vinyl alcohol) (PVA) aqueous solution without functionalization of their surface. A MWNTs–PVA nanocomposite film is prepared by cast deposition from a homogeneous MWNTs–PVA solution. The morphology of the resulting MWNTs–PVA nanocomposite film is characterized by atomic force microscopy (AFM). Well-defined voltammetric responses are observed for the Fe(CN)64-/Fe(CN)63- redox system in aqueous 0.1 M KCl at MWNTs–PVA nanocomposite film modified glassy carbon electrode. In contrast to electrode coated only with PVA, both anodic and cathodic peak currents depended linearly on the square root of the scan rate over the range of 25–200 mV/s at MWNTs–PVA nanocomposite film modified electrode, which suggests diffusion-control and fast electron conduction within the film.