Resistivity study of polyaniline doped with protonic acids

Nanotubular polyaniline (PANI) doped with protonic acids have been synthesized by a "template-free" method. The temperature dependence of resistivity and the influences of doping concentration, dopant, morphology and crystallinity have been studied. A model has been proposed to explain the T-1/2 resistivity. Porous PANI-CSA (camphor sulfonic acid) and PANI-DBSA (dodecylbenzene sulfonic acid) composite films also have been investigated, we have suggested a new equation rho(T) = rho(1)exp(T-0/T)(1/4) + rho(2)(T/T-0)(2) to interpret the transition from negative temperature coefficient of resistivity (TCR) to positive TCR. (C) 2002 Elsevier Science B.V. All rights reserved.