Electrosynthesis and Characterization of PANI and PANI/ ZnO composites films.

The polyaniline (PANI) and ZnO doped polyaniline composite (PANI/ZnO) films were synthesized by electrochemical polymerization, on transparent ITO glass substrate. The deposition was carried out by cyclic voltammetry for 10^th cycle with potential sweep from -200 to 900 mV vs.SCE, in sulfuric acid medium containing aniline monomer precursor and LiClO₄ supporting salt at room temperature. The doping effects of ZnO on PANI properties were studied; electrical properties of PANI and PANI/ZnO composite were estimated from Mott-Schottky analysis which demonstrated an n-type conductivity for all films with carrier concentrations in order of 10¹⁷and 10¹⁹ for PANI and PANI/ZnO composite respectively. The effect of the concentration of ZnO dopant in the electrolyte on the morphology and the composition of the PANI were investigated from scanning electron microscopy coupled Energy Dispersive Spectroscopy analysis (SEM+EDS). UV-VIS was investigated to study the optical characteristics of the films such as transmittance and band gap energy. The characteristics of the films were found to be depended to the concentration of ZnO particles in the electrolyte during electrochemical polymerization. Fourier transform Infrared (FTIR) confirms the links and the interaction between PANI and ZnO dopant.