Electrical, magnetic, and structural properties of lithium salt doped polyaniline

We report the results of temperature dependence of de conductivity sigma (d c)(T), electron paramagnetic resonance (EPR), and X-ray photoelectron spect roscopy (XPS) experiments For the polyaniline (PAN) doped with various lith ium (Li) salts such as LIPF6, LiBF4, LiClO4, LiAsF6, and LiCF3SO3. A quasi one-dimensional (1D) variable range hopping (VRH) model provide the best fi tting for odc(T) the Li salt doped PAN samples, which is similar to that of protonic acid (HCl) doped polyaniline samples. The sigma (dc) and its temp erature dependence vary with the kind of Li salts used. Temperature depende nce of thermoelectric power of PAN doped with LiPF6 shows the metallic beha vior. From EPR experiments, we obtain that chi (P) depends on the kind of L i salts. The results of XPS experiments are discussed to account for the do ping procedure with Li salts. Temperature dependence of EPR linewidths and X-ray diffraction patterns are compared for the various Li salt doped PAN s amples. The insulator-metal transition of PAN-LiPF6 samples is also discuss ed. (C) 2001 Elsevier Science B.V. All rights reserved.