scholarly journals Electrical and Dielectric Properties of Polyaniline and Polyaniline/Montmorillonite Nanocomposite Prepared by Solid Reaction Using Spectroscopy Impedance

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Imene Bekri-Abbes ◽  
Ezzeddine Srasra
Keyword(s):  
Dielectric Properties ◽  
Complex Impedance ◽  
Gravimetric Analysis ◽  
Electrical Measurements ◽  
Solid Reaction ◽  
X Ray ◽  
Impedance Technique ◽  
Different Temperatures ◽  
Electrical And Dielectric Properties ◽  
Uv Visible

The combination of two components with uniform distribution in nanoscale is expected to facilitate wider applications of the material. In this study, polyaniline (PAn) and polyaniline/montmorillonite (Mt) nanocomposite were prepared by solid reaction using persulfate of ammonium as oxidant. The phase composition and morphology of the nanocomposite were characterized by FTIR, UV-visible spectroscopy, X-ray diffractometer, thermal gravimetric analysis, and scanning electron microscopy. The electrical and dielectric properties were determined using spectroscopy impedance. The analysis of UV-visible and FTIR spectroscopy demonstrated that aniline chloride has been polymerized into PAn in its conducting emeraldine form. Thermogravimetric analysis suggested that PAn chains intercalated in the clay host are more thermally stable than those of free PAn prepared by solid-solid reaction. Electrical measurements were carried out using the complex impedance technique in the frequency range of 10−2to 104 Hz at different temperatures. The ac conductivity data of different nanocomposites were analyzed as a function of frequency and temperature. It has been found that the incorporation of inorganic clay phase into polyaniline matrix has an effect on the electrical and dielectric properties of the nanomaterial.

scholarly journals Study of the influence of 2.5% Mg2+ insertion in the B-site of La0.8Ca0.1Pb0.1FeO3 on its structural, electrical and dielectric properties

RSC Advances ◽  
2021 ◽  
Vol 11 (52) ◽  
pp. 33070-33080
Author(s):  
H. Issaoui ◽  
A. Benali ◽  
F. Issaoui ◽  
E. Dhahri ◽  
B. F. O. Costa ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Impedance Spectroscopy ◽  
Physical Properties ◽  
Complex Impedance ◽  
Experimental Techniques ◽  
Complex Impedance Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrical And Dielectric Properties

This work involves the synthesis and study of physical properties of the La0.8Ca0.1Pb0.1Fe0.975Mg0.025O3 compound, which has been characterized by various experimental techniques, such as X-ray diffraction, SEM and complex impedance spectroscopy.

scholarly journals Synthesis of ZnO nanoparticles by a hybrid electrochemical-thermal method: influence of calcination temperature

2015 ◽  
Vol 50 (1) ◽  
pp. 21-28 ◽  
Author(s):  
F Hassan ◽  
MS Miran ◽  
HA Simol ◽  
MAB H Susan ◽  
MYA Mollah
Keyword(s):  
Calcination Temperature ◽  
Zno Nanoparticles ◽  
Zinc Salt ◽  
Thermal Method ◽  
Gravimetric Analysis ◽  
Zno Nps ◽  
X Ray ◽  
Calcination Temperatures ◽  
Ft Ir ◽  
Uv Visible

ZnO nanoparticles (NPs) with size less than 100 nm were successfully prepared by a hybrid electrochemical-thermal method using metallic zinc and NaHCO3 without the use of any zinc salt, template or surfactant. The NPs were characterized by Fourier transform infra-red (FT-IR) spectroscopy, UV-visible spectroscopy, photoluminescence spectroscopy (PL), thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. UV-visible spectral analysis indicated that the particle size increased with increasing calcination temperature. The band gap (3.91-3.83 eV) was higher for synthesized ZnO NPs than their bulk counterparts (3.37 eV). The FT-IR spectra at different calcination temperatures showed the characteristic band for ZnO at 450 cm-1 to be prominent with increasing temperature due to the conversion of precursor into ZnO. The wurtzite hexagonal phase was confirmed by XRD analyses for ZnO NPs calcined at 700oC. The green photoluminescent emission from ZnO NPs at different calcination temperatures is considered to be originated from the oxygen vacancy or interstitial related defects in ZnO. SEM images clearly showed that the NPs are granular and of almost uniform size when calcined at higher temperatures. EDX spectra further confirmed the elemental composition and purity of ZnO obtained on calcination at 700oC. The NPs are well dispersed near or above calcination temperature of 700oC.Bangladesh J. Sci. Ind. Res. 50(1), 21-28, 2015

scholarly journals Estimation of The Electrical and Dielectric Properties For Se98Te2 and Se96Te2X2 (X = Zn and Cd) Amorphous Films.

2021 ◽  
Author(s):  
Amira Shakra ◽  
M. Fadel ◽  
A.E. Kalila
Keyword(s):  
Thin Films ◽  
Dielectric Properties ◽  
Conduction Mechanism ◽  
Charge Carriers ◽  
Amorphous Films ◽  
Thermal Evaporation Method ◽  
Cbh Model ◽  
X Ray ◽  
Electrical And Dielectric Properties ◽  
Quenching Method

Abstract Bulk glassy Se98Te2 and Se96Te2X2 (X = Zn and Cd) were prepared by melting quenching method. Thin films of various thicknesses (200 – 670 nm) were obtained by the thermal evaporation method. The structure of the prepared compositions was investigated by X-ray and EDX analysis. We studied the effect of Zn and Cd addition on the electric and dielectric properties of Se98Te2 thin films. Our measurements were studied in the temperature range (298-323K) below the glass transition temperature and frequency range (100 Hz-1 MHz). DC conductivity showed a single conduction mechanism by hopping of charge carriers at the band edges for the studied system. The dependence of Ac conductivity on frequency is linear with frequency exponent s lies very close to unit and is independent of temperature. This can be explained by the correlated barrier hopping (CBH) model. The dielectric constant ε1 and dielectric loss ε2 noticed to decrease with frequency and increase with temperature. The maximum barrier height Wm was calculated according to Guinitin.

scholarly journals Effects of V2O5 Additive on Structure and Dielectric Properties of BiNbO4 Ceramics

2013 ◽  
Vol 58 (4) ◽  
pp. 1387-1390
Author(s):  
A. Lisińska-Czekaj ◽  
D. Czekaj ◽  
K. Osińska ◽  
M. Adamczyk
Keyword(s):  
Dielectric Properties ◽  
Complex Impedance ◽  
Pressureless Sintering ◽  
Relaxation Phenomena ◽  
Frequency Range ◽  
Reaction Route ◽  
X Ray ◽  
Dielectric Characterization ◽  
Frequency Domains ◽  
Solid State Reaction Route

Abstract Goal of the present research was to investigate the influence of V2O5 additive on the structure and dielectric properties of BiNbO4 ceramics. To fabricate BiNbO4 ceramics with V2O5 added the solid state reaction route and pressureless sintering was utilized. Thus obtained ceramics was characterized in terms of its microstructure (SEM), chemical composition (EDS), phase composition and crystalline structure (X-ray phase and structural analysis, respectively). Also dielectric properties in both temperature and frequency domains were investigated. The impedance spectroscopy was utilized for dielectric characterization and the measurements of complex impedance were performed within the frequency range ν =10Hz-1MHz and temperature range T =RT-550°C. It was found that V2O5 additive changed slightly lattice parameters of BiNbO4 ceramics, decreased porosity of samples and revealled relaxation phenomena within the frequency ranges ν =102-103 Hz and ν =105-106 Hz at temperature T>285°C.

scholarly journals Effect of Fe Substitution on the Structural, Electrical and Dielectric Properties of La0.70Ca0.30MnO3 Cathode for SOFCs

2019 ◽  
Vol 9 (1) ◽  
pp. 324-328
Keyword(s):  
Dielectric Properties ◽  
Single Phase ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Suitable Material ◽  
Density Values ◽  
Electrical And Dielectric Properties ◽  
Fe Substitution

Perovskite solid solutions (La0.70Ca0.30)(FexMn1-x)O3 where x = 0.01, 0.20, 0.30 and 0.40 ceramics were synthesized by solid state reaction route. The structural studies were carried by X-Ray diffraction method and the observed results have indicated that all the prepared samples were crystallized into single phase. The surface morphology was studied by Scanning Electron Microscopy and the images have revealed that grain size has increased with the increasing concentration of Fe. Archimedes principle was used to calculate the density of all the sintered samples and the density values were observed to be in increasing order. The impedance and dielectric properties have been characterized at different ranges of temperature and frequency. The value of electrical conductivity were found to be more than 100 S cm-1 , which indicate that the synthesized material is suitable material for cathode of Solid Oxide Fuel Cell.

Study of Pseudoboehmite Synthesis by Sol-Gel Process

2006 ◽  
Vol 45 ◽  
pp. 260-265 ◽  
Author(s):  
Antônio Hortêncio Munhoz Jr. ◽  
Leila Figueiredo de Miranda ◽  
G.N. Uehara
Keyword(s):  
Sol Gel ◽  
Thermo Gravimetric Analysis ◽  
Ammonium Hydroxide ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Sol Gel Process ◽  
Different Temperatures ◽  
Sol Gel Synthesis

A pseudoboehmite was obtained by sol-gel synthesis using aluminum nitrate as precursor. It was used a 2n full factorial design for studying the effect of the temperature of synthesis, the concentration of ammonium hydroxide, and the radiation dose in the product of sol-gel synthesis. The product of the synthesis was analyzed by scanning electron microscopy, x-ray diffraction of the product (after firing the pseudoboehmite at different temperatures), and it was also analyzed the temperature of endothermic and exothermic transformations using the thermo gravimetric analysis (TG) and differential scanning calorimetry (DSC). The X-ray diffraction data show that α-alumina was obtained at 1100o C.

Morphology, Opto-Electronic and Dielectric Properties of Vacuum Sublimed CuPc Based Thin Films

2019 ◽  
Vol 14 (11) ◽  
pp. 1523-1531
Author(s):  
Manjit Kaur ◽  
Rakesh Dogra ◽  
Narinder Arora ◽  
Navjeet Sharma ◽  
Rajesh Kumar
Keyword(s):  
Thin Films ◽  
Hole Mobility ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Optical Band Gaps ◽  
Different Temperatures ◽  
Evaporation Technique ◽  
Uv Visible ◽  
Substrate Temperatures

AC transport properties and dielectric response of sandwich geometry (Ag/CuPc/Ag) of CuPc(CuPc) thin films deposited using thermal evaporation technique have been studied within frequency range 1 Hz–10 KHz and in temperature range 303–383 K. Scanning electron microscope (SEM) investigations of these films reveal fiber like morphology. Crystalline natures of CuPc films have been characterized using X-ray diffraction for different temperatures. The molecular orientations in films for different substrate temperatures have been confirmed by Raman spectroscopy. The optical band gaps calculated from the UV–Visible absorption spectra is found to lie in the range 3.01–3.15 eV. Electrical conductivity of CuPc films increases with increase of temperature. The hole mobility values of CuPc films at different temperatures have been calculated using negative differential susceptance (–ΔB) technique. Both capacitance and dielectric constant have been found to decrease with the increase of frequency and temperature.

Influence of Substrate Temperature on the Optoelectronic Properties of CuPc Thin Film

2015 ◽  
Vol 1105 ◽  
pp. 123-126
Author(s):  
Tao Yu Zou ◽  
Xiao Lin Ji ◽  
Lei Ming Yu ◽  
Zhen Fang Qiao ◽  
Yi Ji Yang ◽  
...  
Keyword(s):  
Thin Film ◽  
Copper Phthalocyanine ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Different Temperatures ◽  
Uv Visible ◽  
Influence Of Substrate ◽  
Transmission And Absorption ◽  
Substrate Temperatures ◽  
Scanning Electron

The copper phthalocyanine thin films were deposited on quartz and Si/SiO2 substrates at different substrate temperatures. The morphologies, structures and optical properties of CuPc films were characterized by scanning electron microscopy, X-ray diffra ction and UV-Visible spectroscopy. The polymorph of alpha–CuPc was observed in films deposited at temperature ranging from 20°C to 145°C. The transmission and absorption spectra of CuPc films deposited at different temperatures are presented.

Visible Light Photodegradation of Azo Dye by Cu/TiO2

2014 ◽  
Vol 917 ◽  
pp. 151-159 ◽  
Author(s):  
Nadia Riaz ◽  
Chong Fai Kait ◽  
Zakaria Man ◽  
Binay K. Dutta ◽  
Raihan M. Ramli ◽  
...  
Keyword(s):  
Visible Light ◽  
Azo Dye ◽  
Diffuse Reflectance ◽  
Orange Ii ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Uv Visible

Cu/TiO2 photocatalysts with different metal loading were prepared via modified depositionprecipitation method with the intention to reduce the band gap for Orange II degradation and mineralization under visible light radiation. The photocatalysts were characterized using thermal gravimetric analysis, powder X-ray diffraction, diffuse reflectance UV-Visible spectroscopy and field-emission scanning electron microscopy. 10 wt% photocatalysts showed the best performance compared to the bare TiO2.

Electrical Properties of a High-Tc Superconductor-Polymer Compersite

2007 ◽  
Vol 546-549 ◽  
pp. 1989-1992
Author(s):  
Fang Gao Chang ◽  
Kun Fang ◽  
Gui Lin Song
Keyword(s):  
Annealing Temperature ◽  
Solid State Reaction Method ◽  
Gravimetric Analysis ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Different Temperatures ◽  
Zero Resistance ◽  
Composite Samples

A superconductor-polymer composite of Bi1.8Pb0.4Sr2Ca2Cu3Oy and ethylene propylene rubber (EPR) was prepared by conventional solid-state reaction method. The phase structure of the composite was characterized by using x-ray diffraction technique. The resistivity of composite samples annealed at different temperatures was measured between 40K and 300K. The results indicate that the resistivity of the as-prepared composite increases with increasing EPR content and shows essentially a semiconducting behavior above Tc. For fixed EPR content, the resistivity of composite samples decreases with increasing annealing temperature. The composite begins to show some signs of superconducting transition at an annealing temperature of 700 °C and zero resistance is reached for samples sintered at 800°C. Thermal gravimetric analysis (TGA) on the composite confirmed that 65% of the EPR content still present in the superconducting composite samples. SEM was used to investigate the surface morphology of the composites. Preliminary results show that the mechanical properties of the composite have been much improved compared with its parent superconductor ceramics.

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