Nanoferrites as Catalysts and Fillers for Polyaniline/Nanoparticle Composites Preparation

In this paper, we report on the catalytic activity of MFe2O4 nanoparticles (M = Mn, Ni, Cu, Zn, Mg) in the oxidative polymerization of N-(4-aminophenyl)aniline yielding polyaniline/nanoparticle composites. Hydrogen peroxide is used as the oxidizing agent and ferrite nanoparticles play the dual role of reaction catalysts and fillers. The obtained polyaniline/MFe2O4 composites maintained the pristine size of the ferrite crystallites and showed a modest conductive behavior. Polyaniline/MFe2O4 (M = Mn, Ni) composites displayed good dispersion of the nanoparticles in the polyaniline matrix and magnetic hardness intermediate between those of soft M = Fe and hard M = Co composites, evidencing the tunability of the magnetic properties.