Author/Authors :
Joo، نويسنده , , J. and Chung، نويسنده , , Y.C. and LEE، نويسنده , , J.-K. and Hong، نويسنده , , J.K. and Lee، نويسنده , , W.P. and Long، نويسنده , , S.M. and Epstein، نويسنده , , A.J. and Woo، نويسنده , , H.S. and Jang، نويسنده , , K.S. and Oh، نويسنده , , E.J.، نويسنده ,
Abstract :
We report the results of temperature (7) dependence of dc conductivity (σdc), microwave dielectric constant, and EPR experiment for soluble polypyrrole (PPY) samples with different dopants (DBSA and NSA) prepared using various organic solvents (NMP, m-cresol, CHCl3, and DMSO). The three dimensional variable range hopping (VRH) model provides the best fit to the data, while the slope of σdc(T) varies with dopants and solvents used. σdc at room temperature is ~ 0.2 0.01 S/cm and the localization length is estimated as 5 Å, which indicates the relatively strong localization of charge for these materials. We discuss the relation between the polarity of solvent and σdc(T). From EPR experiment, the density of states of the systems is estimated.
Keywords :
Polypyrrole and derivatives , Transport measurements , Conductivity , Hall effect , Solution processing
