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We report the dielectric constant and transport mechanism of intercalated nanoclay−polyaniline composite, an industrially ready to use novel nanocomposite, which is prepared by a simple mechanochemical method. The effects of clay concentration on structure and structure variations on properties were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and impedance spectroscopy (20 Hz−1 MHz and temperature range from 300−380 K). The phenomenon of percolation was observed in these composites. The values of Mott's temperature, density of states at the Fermi level, hopping distance, and barrier height for polyaniline−nanoclay (PANC) composites were calculated. By applying Mott's theory, it is found that the PANC composites obey the one-dimensional variable range hopping mechanism. This type of percolated sample can be used as a nanocapacitor in many devices because of its enhanced transport properties.

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Hole transport properties and Current-Voltage characteristics of the single-layer device in an inverted structure were investigated with spin-coated PEO/PVP/ Cobalt nitrate polyblend electrolyte film as an active layer. A strong correlation between morphology and ionic conductivity was confirmed through XRD, DSC-TGA, SEM and fluorescence spectroscopic techniques. The optical band gap values are in good agreement with the electrochemical band gap. Schottky diode measurements confirmed the formation of p-type semiconductors with PEO/PVP bulk films with cobalt nitrate as a dopant at room temperature. The I-V characteristics are strongly dependent on the salt concentration in the polymer blend. The parameters of diodes such as barrier height, saturation current, and charge carrier concentration were calculated from I-V characteristics. From C-V characteristics a charge carrier concentration in the range of 10 22 cm À3 was obtained for the highest concentration of cobalt nitrate salt in the PEO/PVP blend. A very low energy barrier for hole injection at the anode ΔE h = 0.28 eV was observed.

Methyl blue (MB)-dyed polyethylene oxide (PEO) films were prepared by solution casting technique to study the concentration -dependent conductivity and relaxation mechanism. FTIR spectroscopy confirmed the polymer-dye interactions. XRD and DSC data revealed substantial structural modification such as decrease in degree of crystallinity and reduction in spherulites size of polymer matrix due to the addition of MB. Biphasic nature of these films was observed in SEM images. Impedance and polarization current studies confirmed the ion conduction dominance in the films. The addition of MB dye in PEO resulted in enhanced conductivity due to partial dissolution of the crystalline phase. Electrical conductivity as a function of temperature has been studied. The samples exhibited Arrhenius behavior with two different activation energies. The dielectric studies showed non-Debye type relaxation phenomenon. There was an increase of two orders of magnitude in the conductivity for highest dye concentration. These results are explained in terms of molecular disorder in the PEO-dye phase, heat of fusion, impedance spectra, modulus study and relaxation time.