Insulator-metal transition of Li salts doped polyani line

The results of dc conductivity (σ dc ), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) for Li salts (LiPF 6 , LiBF 4 ) doped polyaniline (PAN) are reported. Temperature (T) dependence of σ dc of LiPF 6 or LiBF 4 doped PAN samples shows lnσ dc T -1/2 arising from a quasi-one-dimensional (ID) variable range hopping (VRH) model. As molar concentration increases, the insulator-metal transition is observed in the results of σ dc and the density of states obtained from EPR experiments. The doping levels of the systems are obtained from XPS nitrogen (N) Is peak analysis. The doping process and the insulator-metal transition of Li salts doped PAN samples are compared with those of HCl doped PAN samples.