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In era of modern technology, light-weight, flexible, low-cost and environmentally safe substrates/electrodes are highly feasible for application in disposable electronics and energy storage devices. This study presents morphological and dielectric characteristics of naked and polyaniline (PANI) coated lignocelluloses fibers, directly collected from self-growing plant, Typha Angustifolia. Impedance spectroscopy measurements performed in frequency range from 0.1 Hz to 10 MHz revealed increase of six orders magnitude in conductive properties of lignocelluloses fibers coated with polyaniline. Dielectric constant of polyaniline coated lignocelluloses fibers also increased by three to five orders magnitude and revealed weak frequency dependence. Presented morphological and dielectric investigations of directly collected and PANI coated lignocelluloses fibers will open possibilities to develop facile, low-cost, flexible and environment friendly paper substrates for energy storage and disposable electronic applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Development of thin, flexible, light-weight, renewable, low-cost, and environmentally friendly electrode materials are highly feasible in era of modern disposable electronic technology. This article presents the synthesis and dielectric studies of polypyrrole (PPy) coated pulp fibers, directly collected from wasted egg holder's tray. PPy coated pulp fibers converted into compact sheet for the development of potential renewable and low-cost electrode materials. The morphology, chemical structure, and thermal stability of naked and PPy coated pulp fibril sheets were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA), respectively. PPy coated pulp fibers revealed better thermal stability and compactness of sheet morphology. Impedance measurements showed a high value of dielectric constant of 1.15 × 106 at 0.5 Hz and conductivity of 7.45 × 10−4 S/cm at room temperature for PPy coated pulp fibril sheet. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42422. [ABSTRACT FROM AUTHOR]

The influence of Ca doping on structural, morphological and dielectric characteristics of Zr 1 - x Ca x TiO 4 ( x = 0 , 0.05, 0.10, 0.15 and 0.2) ceramics has been planned in this effort. Un-doped and Ca-doped ZrTiO 4 (ZT) have been synthesized through a sol–gel auto-combustion approach. The orthorhombic phase of ZT and Ca-doped ZT is confirmed through X-ray diffraction patterns. The variation in structural morphology and particle size due to Ca incorporation in ZT has further been revealed by field emission scanning electron microscopy. The investigation showed that the size of the particle gradually reduced from 0.5 to 0.125 μ m with the increase of Ca content. It was confirmed from Fourier transform infrared spectroscopy that organic content was not found in the prepared samples. Dielectric constant, dielectric loss factor and tangent loss reduce with the increase in frequency and increase in Ca content. These dielectric parameters show independency at a higher frequency. The modulus plots confirmed that the capacitive parts were relatively independent of the frequency, whereas ac conductivity exhibited frequency dependent behaviour i.e., an increase with Ca concentration and with increasing frequency. The impedance plots revealed the resistance dominance due to the grain boundary effect. [ABSTRACT FROM AUTHOR]

Abstract To meet the demand of modern flexible and disposable technology, directly collected lignocelluloses fibers and graphite composite are successfully fabricated with uniformly electrodeposited of thin layers of nickel, silver and nickel. These multilayers (Ni-Ag-Ni) were electrodeposited on lignocelluloses-graphite sheet by using three electrode setup at a constant reduction potential (−0.95 V) between the electrodes. Composition and nanostructures of these nanocomposites (LC-graphite-multilayers) were investigated by using energy dispersive x-ray spectrometry, field emission scanning electron microscopy, Raman spectroscopy, UV–VIS and impedance spectrometer. FE-SEM images revealed that Ni-Ag-Ni layers are uniformly integrated into LC-graphene matrix and EDX analysis confirmed the deposition of multilayers Ni and Ag. Dielectric analysis revealed the non-linear frequency dependent response of the multilayered deposited LC fibers based nanocomposite. Complex impedance spectroscopy analysis presented the multilayered deposited LC fibers based paper electrode for high-tech applications in optical and electronic devices. [ABSTRACT FROM AUTHOR]

In this research work, we have studied the effect of substitution of Sr on the structural, morphological and impedance spectroscopic properties of Zr 1−x Sr x TiO 4 (x = 0, 0.05, 0.10, 0.15 and 0.2), synthesized using sol-gel auto-combustion technique. The X-ray diffraction confirmed the orthorhombic phase. The Fourier transform infrared spectroscopy spectra confirmed that no organic content was present in the sample. Field emission scanning electron microscopic analysis reveals that the particle size reduces from 125 nm to 15 nm. Energy dispersive X-ray technique confirmed the presence of Zr, Ti, Sr and O in the matrix. Dielectric properties are measured at room temperature in the frequency range of 20 Hz to 20 MHz by using the impedance analyzer. Dielectric parameters have been studied by using Koop's theory and Maxwell-Wagner's Model. AC conductivity increases with the increase in frequency and with increasing Sr contents. The impedance plot shows the dominance of grain boundary resistance. Dielectric relaxation process has been studied using Modulus plot. [ABSTRACT FROM AUTHOR]