Synthesis and characterization of polyaniline-Fe3O4 nanocomposite: Electrical conductivity, magnetic, electrochemical studies

Fe3O4 nanoparticles were prepared by hydrolysis reaction of urea in ethylene glycol as solvent at 160 degrees C. The prepared Fe3O4 nanoparticles were incorporated into polyaniline (PANI) matrix during in situ chemical oxidative polymerization of aniline with different molar ratios of aniline:Fe3O4 (19:1, 16:1, 12:1, 9:1) using (NH4)(2)S2O8 as oxidant in aqueous solution of sodium dodecylbenzene sulphonic acid under N-2 atmosphere. Room temperature conductivities of the synthesized PANI, PANI/Fe3O4 (19:1) and PANI/Fe3O4 (9:1) are 3.2 x 10(-4), 1.8 x 10(-5) and 1.0 x 10(-5) S/cm, respectively, indicating decrease of conductivity with increase of Fe3O4 in PANI. Saturation magnetizations of Fe3O4, PANI/Fe3O4 (19:1), and PANI/Fe3O4 (9:1) are 27.5, 5.5 and 6.3 emu/g. respectively, indicating an increase of ferromagnetic interaction with more incorporation of Fe3O4 in PANI matrix, whereas PANI is diamagnetic. Electro-chemical studies shows that Zn-PANI/Fe3O4 (9:1) battery had delivered maximum discharge capacity (78.6 mAh/g) as compared to Zn-PANI battery (50.1 mAh/g) at constant current of 0.5 mA cm(-2). At constant resistance of 1000 Omega, discharge capacities of Zn-PANI/Fe3O4 and Zn-PANI battery are 73.37 and 50.8 mAh/g, respectively. (c) 2010 Elsevier B.V. All rights reserved.