Enhancement in alternating current conductivity of HCl doped polyaniline by modified titania

To enhance the alternating current (AC) conductivity of polyaniline (PANI), modified titanium dioxide (TiO2) prepared by one-step semi-solvothermal method is used to synthesize optimized polyaniline-titanium dioxide (PANI-TiO2) composite by in-situ polymerization method so as to form p-n heterojunction interface between them. The prepared samples were characterized by FTIR, XRD and SEM techniques. Nanostructure of the composite was confirmed from TEM technique. Increased conductivity of the composite compared to that of PANI due to interfacial interaction between PANI and TiO2 in it was confirmed from FTIR, XRD and SEM studies. Conduction in both PANI and the composite by hopping mechanism was confirmed by studying the power law behavior of their AC conductivity. High values of the real part of the complex dielectric constant and dielectric loss tangent at low frequency for both PANI and the composite were confirmed to be due to interfacial Maxwell-Wagner polarization. Increased conductivity of the composite as compared to that of pristine PANI was confirmed by a shift of the peak towards a relatively higher frequency in the plot of the imaginary part of the complex electric modulus with frequency.