Polyaniline–niobium oxide nanohybrids with photocatalytic activity under visible light irradiation

Abstract

In this study, we report the production of polyaniline and niobium oxide hybrids synthesized by the direct reaction between a niobium peroxyoxalate complex and anilinium salt in an aqueous medium. The hybrid materials obtained show the polyaniline in its most conductive form (the emeraldine salt), with oxalate acting as the doping anion and Nb₂O₅ nanoparticles homogeneously dispersed in the PANI matrix. We also evaluated the electrical and photocatalytic properties of this material. The measured electrical conductivity varied from 10⁻² to 10⁻³ S cm⁻¹, which is three orders of magnitude higher than that observed for neat Nb₂O₅. The photocatalytic activity was investigated using the standard reaction of discoloration of methylene blue (MB) dye in an aqueous solution. The hybrids showed better MB adsorption capacity and were also more efficient in decolorizing the solution under visible light irradiation than neat Nb₂O₅.