Doping of emeraldine base with the monovalent bridging iron oxalate ions and their transformation into nanostructured conducting polymer composites

Synthesis of emeraldine base doped with the mixed valent bridging iron oxal ate complex was done in the presence of varying quantities of H2O2. Charact erization of the samples was carried out using elemental analyzer, FTIR spe ctrophotometer, scanning electron microscopy. four probe technique and Moss bauer spectroscopy. It has been observed that the reaction conditions are s uch that they bring about the partial reduction of iron from the +3 state t o the +2 state, resulting in the formation of monovalent bridging iron oxal ate complex dopant ion with iron existing in both +2 and +3 oxidation state s. H2O2 at higher concentrations during the reaction is found to influence the polymer backbone, thus affecting the conductivity of the samples. Nanos ized particles of oxides of iron in +2 and +3 oxidation states are formed i n the polyaniline matrix on simple chemical treatment of the doped samples with an alkali. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.