PAni-SnO2 Nanocomposite: Irradiation Induced Charge Transport Processes

2013 ◽  
Vol 209 ◽  
pp. 39-43
Author(s):  
Smritimala Sarmah ◽  
Ashok Kumar
Keyword(s):  
Electrical Conductivity ◽  
Conduction Mechanism ◽  
Sno2 Nanoparticles ◽  
Oxidative Polymerization ◽  
Transport Processes ◽  
X Ray Diffraction ◽  
Ac Electrical Conductivity ◽  
Dimensional Variable ◽  
Hopping Model ◽  
Variable Range Hopping Model

The films of polyaniline–tin oxide (PAni–SnO2) nanocomposites were synthesized by chemical oxidative polymerization technique. These films were irradiated with 90 MeV O7+ ions at the fluences of 5×1010, 1×1011, 5×1011, and 1×1012 ions/cm2. X-ray diffraction studies show that microstrain and domain crystallite size of SnO2 nanoparticles in PAni matrix increase with the increase of ion fluence, resulting in highly ordered PAni–SnO2 nanocomposites. DC electrical conductivity is found to increase with the increase of fluence and conduction mechanism follows a quasi one-dimensional variable-range hopping model. AC electrical conductivity also increases with the increase of ion fluence and obeys correlated barrier-hopping model.

scholarly journals Electrical Conductivity and Chemical Equilibria of Coordination Biopolymeric Cerium (IV)-Alginate Complex with Correlation between the Structure and Complex Stability

2015 ◽  
Vol 7 (2) ◽  
pp. 57 ◽  
Author(s):  
Ishaq Zaafarany ◽  
Hatem Altass ◽  
Jabir Alfahemi ◽  
Khalid Khairou ◽  
Refat Hassan
Keyword(s):  
Electrical Conductivity ◽  
Conduction Mechanism ◽  
Research Study ◽  
Coordination Geometry ◽  
Complex Stability ◽  
X Ray Diffraction ◽  
Chemical Equilibria ◽  
X Ray ◽  
Infrared Absorption Spectra ◽  
Diffraction Patterns

In this research study, the cross-linked cerium (IV)-alginate complex, as coordination biopolymeric compound in the granules form, was prepared. It has been indicated from the x-ray diffraction patterns that the nature of alginate complex is amorphous. Additionally, it has been revealed from the infrared absorption spectra that cerium (IV) chelates the alginate macromolecular chains in the complex. The study has displayed that the range of us OCO- is 1424 cm-1and the range of uasOCO- is 1605 cm-1. This indicates that a complexation type between the cation Ce4+ and both carboxylate and hydroxyl functional groups of alginate macromolecule is usually takes place. The study has also measured the electrical conductivity (s) of coordination biopolymeric cerium (IV)-alginate complex, as function of temperature. It has been indicated from the measured value of the electrical conductivity, i.e., 1.04 x10-9 Siemens at 20oC that the conductance of the complex lies in the range of semiconductors. The research has profoundly discussed with evaluation of the thermodynamic parameters. Afterwards, appropriate conduction mechanism based on the electrical conductivity and chemical equilibrium has also been suggested and discussed in terms of the complex stability in correlation with its coordination geometry.

FACILE PREPARATION AND CHARACTERIZATION OF GRAPHENE NANOSHEET/POLYANILINE NANOFIBER THERMOELECTRIC COMPOSITES

2013 ◽  
Vol 06 (05) ◽  
pp. 1340002 ◽  
Author(s):  
YONG DU ◽  
KEFENG CAI ◽  
SHIRLEY ZHIQI SHEN
Keyword(s):  
Electrical Conductivity ◽  
Room Temperature ◽  
Oxidative Polymerization ◽  
X Ray Diffraction ◽  
Composite Powders ◽  
Graphene Nanosheet ◽  
X Ray ◽  
Pani Composite ◽  
Composite Pellets

Graphene nanosheet (GNs)/polyaniline (PANI) nanofiber composites were prepared by oxidative polymerization of aniline in a GNs dispersed 1 mol/L HCl solution. The phase composition of the composites was analyzed by Fourier Transform Infrared Spectroscopy and X-ray Diffraction. The thermoelectric properties of the composite powders, after cold pressing into pellets, were measured at room temperature. As the content of GNs increased from 0 to 40 wt.%, the electrical conductivity and Seebeck coefficient of the composite pellets increased simultaneously; especially the electrical conductivity increased dramatically from 15.4 to 120.1 S/cm. The highest power factor (~ 394.4 × 10-8 Wm-1K-2) was obtained from the 40 wt.% GNs/PANI composite sample, which is ~200 times as high as that of HCl -doped PANI.

scholarly journals Analysis of X-ray structure, dielectric properties and AC conductivity of (4E)-2-amino-3-cyanobenzo[b]oxocin-6-one

2016 ◽  
Vol 34 (2) ◽  
pp. 386-392 ◽  
Author(s):  
H.A.M. Ali ◽  
Magdy A. Ibrahim
Keyword(s):  
Crystal Structure ◽  
Activation Energy ◽  
Electrical Conductivity ◽  
Dielectric Constant ◽  
Relaxation Time ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Ac Electrical Conductivity ◽  
X Ray ◽  
Different Temperatures

AbstractThe crystal structure of (4E)-2-amino-3-cyanobenzo[b]oxocin-6-one, denoted as 4(E)-ACBO, was analyzed using X-ray diffraction technique. The dielectric and AC electrical conductivity measurements of the bulk 4(E)-ACBO in the form of pellet were studied in the range of frequency 42 Hz to 5 MHz and the temperature range of 303 K to 373 K. The temperature and frequency dependence of dielectric constant (∊1), dielectric loss (∊2) and AC electrical conductivity (σAC) were investigated. The relaxation time (τ) for electrons to hop over a barrier of height WH was calculated at different temperatures. The AC activation energy was determined from the temperature dependence of σAC at different frequencies.

ELECTRICAL RESISTIVITY AND AC SUSCEPTIBILITY STUDIES IN Sr1-xLaxMnO3

2006 ◽  
Vol 20 (24) ◽  
pp. 1517-1528 ◽  
Author(s):  
MANORANJAN KAR ◽  
S. RAVI
Keyword(s):  
Ac Susceptibility ◽  
X Ray Diffraction ◽  
Space Group ◽  
Solid State Route ◽  
Doped Materials ◽  
Antiferromagnetic Transitions ◽  
Diffraction Patterns ◽  
Hopping Model ◽  
Variable Range Hopping Model ◽  
Temperature Resistivity

Electron-doped Sr 1-x La x MnO 3(0≤x≤0.50) and hole-doped (x=0.70 and 0.82) samples have been prepared by solid state route. X-ray diffraction patterns could be refined using P63 space group for x≤0.30 and [Formula: see text] space group for x≥0.40. Temperature variation of AC susceptibility measurements show that all the electron-doped materials exhibit paramagnetic to ferromagnetic transitions with the transition temperatures ranging from 375 to 393 K, followed by low temperature antiferromagnetic transitions. The ferromagnetic maximum susceptibility is found to increase systematically with La doping, i.e. with increase in Mn 3+ ions. The high temperature resistivity data could be analyzed using the Mott-variable range hopping model. The hole-doped materials exhibit ferromagnetic to paramagnetic transition.

scholarly journals Studies on AC Electrical Conductivity of CdCl2Doped PVA Polymer Electrolyte

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
M. B. Nanda Prakash ◽  
A. Manjunath ◽  
R. Somashekar
Keyword(s):  
Electrical Conductivity ◽  
Ionic Conductivity ◽  
Polymer Electrolytes ◽  
Profile Analysis ◽  
Line Profile Analysis ◽  
Solvent Casting ◽  
X Ray Diffraction ◽  
Casting Method ◽  
Ac Electrical Conductivity ◽  
X Ray

PVA-based polymer electrolytes were prepared with various concentrations of CdCl2using solvent casting method. Prepared polymer films were investigated using line profile analysis employing X-ray diffraction (XRD) data. XRD results show that the crystallite size decreases and then increases with increase in CdCl2. AC conductivity in these polymer increases films first and then decreases. These observations are in agreement with XRD results. The highest ionic conductivity of 1.68E− 08 Scm−1was observed in 4% of CdCl2in PVA polymer blend. Crystallite ellipsoids for different concentrations of CdCl2are computed here using whole pattern powder fitting (WPPF) indicating that crystallite area decreases with increase in the ionic conductivity.

DC electrical conductivity retention and acetone/acetaldehyde sensing on polythiophene/molybdenum disulphide composites

2021 ◽  
pp. 096739112110027
Author(s):  
Ahmad Husain ◽  
Sharique Ahmad ◽  
Shahid Pervez Ansari ◽  
Mohammad Omaish Ansari ◽  
Mohammad Mujahid Ali khan
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Room Temperature ◽  
Oxidative Polymerization ◽  
Lone Pair ◽  
Electronic Interaction ◽  
X Ray Diffraction ◽  
Molybdenum Disulphide ◽  
Dc Electrical Conductivity ◽  
Conductivity Retention

In this study, polythiophene (PTh) and a series of polythiophene/molybdenum disulphide (PTh/MoS2) composites were prepared by in-situ chemical oxidative polymerization method using anhydrous ferric chloride (FeCl3) as an oxidant and chloroform (CHCl3) as a solvent. The successful formation of PTh and PTh/MoS2 composites were confirmed by various techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmittance electron microscopy (TEM). DC electrical conductivity and acetone/acetaldehyde sensing studies were carried out by a four-in-line probe device. PTh/MoS2 composites exhibited significantly improved DC electrical conductivity and acetone/acetaldehyde sensing properties as compared to PTh. The electrical properties were investigated in terms of initial conductivity (i.e. conductivity at room temperature) as well as retention of conductivity, i.e. stability under isothermal and cyclic ageing conditions. The maximum initial conductivity, along with the highest conductivity retention, was observed for PTh/MoS2-2 (PTh/MoS2 composite comprising 10% MoS2 with respect to the weight of thiophene monomer). The initial DC electrical conductivity of PTh, PTh/MoS2-1, PTh/MoS2-2 and PTh/MoS2-3 was found to be 5.72 × 10−5 Scm−1, 4.03 × 10−4 Scm−1, 1.09 × 10−3 Scm−1 and 8.96 × 10−4 Scm−1, respectively. The sensing performance at room temperature has been studied in terms of % sensing response, response/recovery time. All the PTh/MoS2 composites based sensors performed much better than PTh. The % sensing response of PTh, PTh/MoS2-1, PTh/MoS2-2 and PTh/MoS2-3 based pellet-shaped sensors towards acetone/acetaldehyde were affirmed as 30.6/22.9, 69.9/47.3, 93.7/70.3, 78.1/65.1, respectively. The purposed sensing mechanism involved the adsorption of acetone/acetaldehyde vapours on the surface of the sensors where electronic interaction between lone pair of electrons on oxygen atoms of the carbonyl group and charge carriers of PTh was responsible for the change in conductivity.

scholarly journals Dielectric Permittivity, AC Electrical Conductivity and Conduction Mechanism of High Crosslinked-Vinyl Polymers and Their Pd(OAc)2 Composites

Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 3005
Author(s):  
Elsayed Elbayoumy ◽  
Nasser A. El-Ghamaz ◽  
Farid Sh. Mohamed ◽  
Mostafa A. Diab ◽  
Tamaki Nakano
Keyword(s):  
Electrical Conductivity ◽  
Dielectric Permittivity ◽  
Conduction Mechanism ◽  
Quantum Mechanical ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Ac Electrical Conductivity ◽  
Vinyl Polymers ◽  
Vinyl Polymer ◽  
Poly Ethylene

Semiconductor materials based on metal high crosslinked-vinyl polymer composites were prepared through loading of Pd(OAc)2 on both Poly(ethylene-1,2-diyl dimethacrylate) (poly(EDMA)) and poly(ethylene-1,2-diyl dimethacrylate-co-methyl methacrylate) (Poly(EDMA-co-MMA)). The thermochemical properties for both poly(EDMA) and poly(EDMA-co-MMA) were investigated by thermal gravimetric analysis TGA technique. The dielectric permittivity, AC electrical conductivity and conduction mechanism for all the prepared polymers and their Pd(OAc)2 composites were studied. The results showed that the loading of polymers with Pd(OAc)2 led to an increase in the magnitudes of both the dielectric permittivity and AC electrical conductivity (σac). The value of σac increased from 1.38 × 10−5 to 5.84 × 10−5 S m−1 and from 6.40 × 10−6 to 2.48 × 10−5 S m−1 for poly(EDMA) and poly(EDMA-co-MMA), respectively, at 1 MHz and 340 K after loading with Pd(OAc)2. Additionally, all the prepared polymers and composites were considered as semiconductors at all the test frequencies and in the temperature range of 300–340 K. Furthermore, it seems that a conduction mechanism for all the samples could be Quantum Mechanical Tunneling (QMT).

scholarly journals Structural and Dielectric Properties of (1-x) (Al0.2La0.8TiO3) + (x) (BiZnFeO3) (x = 0.2 - 0.8) Nanocomposites

2021 ◽  
Author(s):  
A. Mallikarjuna ◽  
N. Suresh Kumar ◽  
T. Anil Babu ◽  
S. Ramesh ◽  
Chandra Babu Naidu K
Keyword(s):  
Electrical Conductivity ◽  
Dielectric Constant ◽  
Phase Transformation ◽  
Dielectric Properties ◽  
Dielectric Behavior ◽  
Perfect Absorber ◽  
X Ray Diffraction ◽  
Ac Electrical Conductivity ◽  
X Ray ◽  
Diffraction Patterns

Abstract (1-x) (Al0.2La0.8TiO3) + (x) (BiZnFeO3) (x = 0.2 - 0.8) [ALTBZFO] nanocomposites were synthesized via hydrothermal method. The X-ray diffraction patterns indicated the phase transformation from tetragonal to cubic for x = 0.2 to 0.4 - 0.8 samples, respectively. The surface morphology showed the existence of nanospheres like structures. At 1 MHz frequency also, the dielectric constant was increased from 230 to 710 for x = 0.2 – 0.6 samples, respectively. But, interestingly, x = 0.6 nanocomposite exhibited the negative dielectric behavior having the dielectric constant (ε') ~ -58.5 and dielectric loss (ε") ~ -417 at 8 MHz. Likewise, x = 0.6 sample showed ac-electrical conductivity (σac) -0.159 S/cm at 6 MHz. Hence, these kinds of materials can provide high charge stored capacitor, and perfect absorber applications.

scholarly journals Dielectric Properties, AC Conductivity, and Electric Modulus Analysis of Bulk Ethylcarbazole-Terphenyl

2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Hussam Bouaamlat ◽  
Nasr Hadi ◽  
Najat Belghiti ◽  
Hayat Sadki ◽  
Mohammed Naciri Bennani ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Ac Conductivity ◽  
Conduction Mechanism ◽  
Electric Modulus ◽  
X Ray Diffraction ◽  
X Ray ◽  
Universal Power Law ◽  
Electrical And Dielectric Properties ◽  
Increasing Temperature ◽  
Hopping Model

Electrical and dielectric properties for bulk ethylcarbazole-terphenyl (PEcbz-Ter) have been studied over frequency range 1 kHz–2 MHz and temperature range (R.T –120°C). The copolymer PEcbz-Ter was characterised by using X-ray diffraction. The frequency dependence of the dielectric constant (εr′) and dielectric loss (εr″) has been investigated using the complex permittivity. εr′ of the copolymer decreases with increasing frequency and increases with temperature. AC conductivity (σac) data were analysed by the universal power law. The behaviour of σac increases with increasing temperature and frequency. The change of the frequency exponent (s) with temperature was analysed in terms of different conduction mechanisms, and it was found that the correlated barrier-hopping model is the predominant conduction mechanism. The electric modulus was used to analyze the relaxation phenomenon in the material.

Electrical conduction mechanism in films of Se80−xTe20Bix (0 ≤ x ≤ 12) glassy alloys

2019 ◽  
Vol 97 (2) ◽  
pp. 222-226 ◽  
Author(s):  
Deepika ◽  
Hukum Singh
Keyword(s):  
Electrical Conductivity ◽  
Physical Vapor Deposition ◽  
Conduction Mechanism ◽  
Charge Carriers ◽  
X Ray Diffraction ◽  
Glassy Alloys ◽  
Transmission Electron ◽  
Physical Vapor Deposition Method ◽  
Temperature Ranges ◽  
Lower Temperature

This paper reports the study of DC electrical conductivity of films of Se80−xTe20Bix (0 ≤ x ≤ 12) glasses prepared using physical vapor deposition method. The films were structurally characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM results indicate the formation of nanorods within the films. The electrical conductivity of the samples was studied using Keithley electrometer in the temperature range 303–373 K. The results show that conduction in these samples takes place via thermally assisted tunnelling and variable range hopping of charge carriers corresponding to higher and lower temperature ranges, respectively. Further, it was found that the conductivity increases with increase in Bi concentration in Se–Te system. This has been explained on the basis of chemically ordered network model. It was also found that nanorod formation improves the electrical conductivity of Se–Te–Bi system compared to bulk Se–Te–Bi system.

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