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Poly(o-toluidine) (POT) thin films were synthesized by electrochemical polymerization under cyclic voltammetric conditions from o-toluidine monomer in an aqueous solution of HCl as a supporting electrolyte. The electrosynthesized films were characterized by UV-Visible, FT-Raman, and FTIR spectroscopies. The optical transmissions of the as-deposited films were measured in the 400–900 nm wavelength range. These measurements showed that the optical band gap of the polymer films is in the order of 2.52 eV. The FT-Raman and FTIR measurements showed that the POT film is composed of imine and amine units. ITO/POT/Al devices were fabricated by thermal evaporation of aluminum circular contacts on films deposited on ITO-coated glass. The nonlinear current-voltage characteristics of these devices indicate a rectifying behavior. The diode parameters were calculated from I-V characteristics using the modified Shockley equation. The measured C-V and C-F characteristics are presented.

In this paper, n-Zinc oxide=p-copper oxide heterojunctions were fabricated by RF-sputtering on indium tin oxide-covered glass substrates. The structural and optical properties of the copper oxide and zinc oxide films were analyzed by X-ray diffraction, Fourier transform infrared, scanning electronic microscopy and ultraviolet-visible spectroscopy. The electrical junction properties were investigated by current-voltage (I-V) characteristics. Additionally, both capacitance (C) and conductance (G) versus frequency ( f ) measurements were realized at room temperature. The junctions showed a rectifying behavior, and C and G varied with both voltage and frequency.

Composite materials were made by mixing powders ofBa1−xSrxTiO3(x=0.2and 0.4) ceramics and epoxy resin with various volume fractions (vol%). Dielectric measurements of these composites were performed as a function of filler ratio in the range 100–360°K at 10 KHz. The dielectric constant of the composite increased with increasing volume fraction varies slightly with temperature. The 20 vol% of BST(0.4)-epoxy composite had the highest dielectric constant of 19.4 and dielectric loss tangent of 0.027. Among the dielectric mixing models presented, the model of Lichtenecker shows the best fit to the experimental data for both composites.