Studies on DC Conductivity and Magnetic Susceptibility of Polyaniline Doped with Different Acids

Abstract

We report a comparative study among four kinds of polyaniline (PANI) synthesized with four different kinds of acids, under the same conditions for synthesis; PANI-HCl, PANI-H 2 SO 4 , PANI-H 3 PO 4 and PANI-C 4 H 6 O 6 . We measured the temperature dependence of the dc conductivity σ dc ( T ) and the magnetic susceptibility χ tot ( T ). The room-temperature conductivity of HCl and H 2 SO 4 -polyaniline was 5–8 times higher than that of H 3 PO 4 and C 4 H 6 O 6 -polyaniline, in which the values of 18.1, 16.8, 3.8 and 1.85 S/cm were found, respectively. The best fit for our dc conductivity data was obtained using the quasi-one-dimensional variable-range hopping (Q1D VRH) model between nearest neighbors. Polyaniline reported in this paper leads to a high magnetic susceptibility χ tot (at T =295 K) of 10 -4 emu/mol.2rings. This is one or two orders of magnitude higher than those reported earlier for polyaniline. Data on σ dc ( T ) and χ tot ( T ) are also discussed.