The Electrical Conductivity and Infrared Properties of Ba-Doped SmCoO3-δ Composite Oxides

2011 ◽  
Vol 239-242 ◽  
pp. 687-690
Author(s):  
Le Chen ◽  
Chun Hua Lu ◽  
Yuan Zheng Zhao ◽  
Wen Yan Zhang ◽  
Ya Ru Ni ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Double Perovskite ◽  
Infrared Emissivity ◽  
Electrical Behavior ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Composite Oxides ◽  
Solid State Reaction Route ◽  
Emissivity Measurements

Layered SmBaCo2O5+δ with the cation-ordered double perovskite structure were synthesized by the solid-state reaction route and characterized by thermal analysis, X-ray diffraction, infrared spectrum, electrical conductivity and infrared emissivity. The Sm1-xBaxCoO3(SBCO) system shows the different crystal structures with the variation of barium content, which results in the different electrical behavior. The electrical conductivity reaches maximum when x is 0.5 with SmBaCo2O5.54 phase. The infrared absorption occurs at about 600 cm-1 for all the samples which were attributed to Co-O stretching modes. The peak shifted to a lower frequency with the increase of doping level. In addition, the comparison of electrical and emissivity measurements suggested that variation of infrared emissivity is in agreement with the electrical properties.

Crystal Structure of the New Phosphate AgMnPO4

2009 ◽  
Vol 64 (7) ◽  
pp. 875-878 ◽  
Author(s):  
Hamdi Ben Yahia ◽  
Etienne Gaudin ◽  
Jacques Darriet
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Solid State Reaction Route ◽  
Symmetry Space ◽  
Symmetry Space Group ◽  
Silver Atoms

The new compound AgMnPO4 has been synthesized by a solid-state reaction route. Its crystal structure was determined from single-crystal X-ray diffraction data. AgMnPO4 crystallizes with triclinic symmetry, space group P1̄, a = 9.6710(6), b = 5.695(2), c = 6.629(3) Å , α = 102.55(3), β = 105.85(2), γ = 80.70(2)◦, and Z = 4. Its structure is built up from MnO6, MnO5 and PO4 polyhedra forming tunnels filled with silver atoms.

scholarly journals Influence of Processing Conditions on Crystal Structure of Bi6Fe2Ti3O18 Ceramics

2016 ◽  
Vol 61 (2) ◽  
pp. 881-886 ◽  
Author(s):  
A. Lisińska-Czekaj ◽  
M. Lubina ◽  
D. Czekaj ◽  
M. Rerak ◽  
B. Garbarz-Glos ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Ambient Air ◽  
Processing Conditions ◽  
Orthorhombic Structure ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Number Of Layers ◽  
Solid State Reaction Route ◽  
Diffraction Patterns

Abstract Aim of the present research was to apply a solid state reaction route to fabricate Aurivillius-type ceramics described with the formula Bi6Fe2Ti3O18 (BFTO) and reveal the influence of processing conditions on its crystal structure. Pressureless sintering in ambient air was employed and the sintering temperatures were 850 and 1080 °C. It was found that the fabricated BFTO ceramics were multiphase ones. They consisted of two Bim+1Fem-3Ti3O3m+3 phases, namely the phase with m=5 (i.e. the stoichiometric phase) and m=4 (i.e. the phase with a reduced number of layers in the slab). Detailed X-ray diffraction patterns analysis showed that both phases adopted the same orthorhombic structure described with Fmm2 (42) space group. The ratio of weight fractions of the constituent phases (m=5): (m=4) was ~30:70.

scholarly journals Dielectric Properties of 0.95 ( )-0.05 Composites

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Rekha Rani ◽  
Parveen Kumar ◽  
J. K. Juneja ◽  
K. K. Raina ◽  
Chandra Prakash
Keyword(s):  
Dielectric Properties ◽  
Lead Zirconate Titanate ◽  
Nickel Ferrite ◽  
Lead Zirconate ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Magnetoelectric Composites ◽  
Solid State Reaction Route

We report studies on dielectric properties of magnetoelectric composites of La-substituted lead zirconate titanate (PLZT) and zinc-doped nickel ferrite (NZF) with compositional formula 0.95 Pb1-3x/2LaxZr0.65Ti0.35O3-0.05 Ni0.8Zn0.2Fe2O4(, 0.01, 0.02, and 0.03). The materials were synthesized by conventional solid state reaction route. The presence of individual phases (PLZT and NZF) was confirmed by using X-ray diffraction technique. Dielectric properties were studied as a function of temperature and frequency. Significant improvement was observed in dielectric properties with addition of La.

Dielectric Behavior of (1-X)BaTiO3-XCaCu2.94Mn0.06Ti4O12 Composite Ceramics

2008 ◽  
Vol 368-372 ◽  
pp. 62-64 ◽  
Author(s):  
Gang Yang ◽  
Zhen Xing Yue ◽  
Xiang Li ◽  
Tian Wang ◽  
Long Tu Li
Keyword(s):  
Solid State ◽  
Dielectric Loss ◽  
Dielectric Permittivity ◽  
Solid State Reaction ◽  
Dielectric Behavior ◽  
Composite Ceramics ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Solid State Reaction Route

(1-X)BaTiO3-XCaCu2.94Mn0.06Ti4O12 (BTO-CCMTO) composite ceramics with X =0.1 and 0.2 were prepared through solid state reaction route. X-ray diffraction (XRD) analyses showed that a co-existence structure of BTO and CCMTO phase can be realized when the sample was sintered at 950°C. Furthermore, influences of CCMTO on the dielectric behaviors of the BTO-CCMTO composite ceramics were investigated. The results showed that the dielectric permittivity of the BTO-CCMTO composite ceramics increases with increasing amounts of CCMTO and the Curie peak of the pure BTO ceramics is greatly suppressed due to the addition of CCMTO. The dielectric loss of the BTO-CCMTO composite ceramics can be kept in the same magnitude order as that of the BTO ceramics.

FERROELECTRIC AND PIEZOELECTRIC PROPERTIES OF Gd3+ AND Y3+ MODIFIED PKN ELECTROCERAMICS

2008 ◽  
Vol 22 (15) ◽  
pp. 1515-1523
Author(s):  
K. SAMBASIVA RAO ◽  
D. MADHAVA PRASAD ◽  
P. MURALI KRISHNA ◽  
JOON HYUNG LEE
Keyword(s):  
Piezoelectric Properties ◽  
Hysteresis Loops ◽  
X Ray Diffraction ◽  
Reaction Route ◽  
X Ray ◽  
Polarization Electric Field ◽  
Solid State Reaction Route ◽  
Quality Factor Q ◽  
Ferroelectric And Piezoelectric Properties ◽  
Piezoelectric Constants

Ceramics with the composition Pb 1-x K 2x-3y M y Nb 2 O 6 (PKMN) with x = 0.29, y = 0.145 and M = Gd 3+, Y 3+ were synthesized by the solid-state reaction route between the corresponding oxides and carbonates. The crystal structure was confirmed by X-ray diffraction (XRD). The temperature dependence of dielectric properties were measured from 35 to 595°C. Well-developed P–E (polarization–electric field) hysteresis loops were observed in the materials. Determining the piezoelectric constants, Kp = 20%, Kt = 49%, d33 = 110, and quality factor, Qm = 33, reveals that the material Y 3+-modified PKN can be useful for transducer applications.

Structure and Conductivity of Iodine-Doped C60 Thin Films

1994 ◽  
Vol 359 ◽  
Author(s):  
Jun Chen ◽  
Haiyan Zhang ◽  
Baoqiong Chen ◽  
Shaoqi Peng ◽  
Ning Ke ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Room Temperature ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
X Ray ◽  
Thermally Activated ◽  
Order Of Magnitude

ABSTRACTWe report here the results of our study on the properties of iodine-doped C60 thin films by IR and optical absorption, X-ray diffraction, and electrical conductivity measurements. The results show that there is no apparent structural change in the iodine-doped samples at room temperature in comparison with that of the undoped films. However, in the electrical conductivity measurements, an increase of more that one order of magnitude in the room temperature conductivity has been observed in the iodine-doped samples. In addition, while the conductivity of the undoped films shows thermally activated temperature dependence, the conductivity of the iodine-doped films was found to be constant over a fairly wide temperature range (from 20°C to 70°C) exhibiting a metallic feature.

scholarly journals Investigation and Modeling of the Electrical Conductivity of Graphene Nanoplatelets-Loaded Doped-Polypyrrole

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1034
Author(s):  
Oladipo Folorunso ◽  
Yskandar Hamam ◽  
Rotimi Sadiku ◽  
Suprakas Sinha Ray ◽  
Neeraj Kumar
Keyword(s):  
Electrical Conductivity ◽  
Structural Changes ◽  
Spherical Shape ◽  
Graphene Nanoplatelets ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermogravimetric Analyzer ◽  
Energy Storage Applications ◽  
Electrical Conductivity Data

In this study, a hybrid of graphene nanoplatelets with a polypyrrole having 20 wt.% loading of carbon-black (HGPPy.CB20%), has been fabricated. The thermal stability, structural changes, morphology, and the electrical conductivity of the hybrids were investigated using thermogravimetric analyzer, differential scanning calorimeter, X-ray diffraction analyzer, scanning electron microscope, and laboratory electrical conductivity device. The morphology of the hybrid shows well dispersion of graphene nanoplatelets on the surface of the PPy.CB20% and the transformation of the gravel-like PPy.CB20% shape to compact spherical shape. Moreover, the hybrid’s electrical conductivity measurements showed percolation threshold at 0.15 wt.% of the graphene nanoplatelets content and the curve is non-linear. The electrical conductivity data were analyzed by comparing different existing models (Weber, Clingerman and Taherian). The results show that Taherian and Clingerman models, which consider the aspect ratio, roundness, wettability, filler electrical conductivity, surface interaction, and volume fractions, closely described the experimental data. From these results, it is evident that Taherian and Clingerman models can be modified for better prediction of the hybrids electrical conductivity measurements. In addition, this study shows that graphene nanoplatelets are essential and have a significant influence on the modification of PPy.CB20% for energy storage applications.

Dehydration and decomposition of pyrophyllite at high pressures: electrical conductivity and X-ray diffraction studies to 5 GPa

1997 ◽  
Vol 34 (6) ◽  
pp. 875-882 ◽  
Author(s):  
Tara L. Hicks ◽  
Richard A. Secco
Keyword(s):  
Electrical Conductivity ◽  
South African ◽  
Pressure Dependence ◽  
High Pressures ◽  
Ionic Conduction ◽  
Temperature Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Dependence Of Conductivity

The dehydration and decomposition of South African pyrophyllite were studied in the pressure range 2.5–5.0 GPa and in the temperature (T) range 295–1473 K using both in situ electrical conductivity measurements and X-ray diffraction studies on the recovered samples. Activation energies for conduction (Qc) vary in the range 0.02–0.07 eV for T ≤ 500 K where the dominant conduction mode is electronic, and Qc is in the range 1.10–1.28 eV for T ≥ 500 K where ionic conduction dominates. Abrupt changes in the isobaric temperature dependence of conductivity mark the onset of dehydration and subsequent decomposition into kyanite plus quartz–coesite. At 2.5 GPa, South African pyrophyllite forms the dehydroxylate phase at 760 K with a pressure dependence of ~30 K/GPa and complete decomposition follows at 1080 K with a pressure dependence of ~41 K/GPa. The resulting pressure–temperature phase diagram is in very good agreement with many previous studies at 1 atm (101.325 kPa).

Lateral deformations of a crystal of potassium acid phthalate in an external electric field

2021 ◽  
Vol 54 (5) ◽  
pp. 1317-1326
Author(s):  
Arsen Petrenko ◽  
Nataliya Novikova ◽  
Alexander Blagov ◽  
Anton Kulikov ◽  
Yury Pisarevskii ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electrical Conductivity ◽  
Electric Field ◽  
External Electric Field ◽  
Applied Field ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Potassium Acid Phthalate ◽  
Acid Phthalate

The anisotropy of deformations in potassium acid phthalate crystals arising under the action of an external electric field up to 1 kV mm−1 applied along the [001] polar axis was studied using X-ray diffraction methods at room temperature. Electrical conductivity was measured and rocking curves for reflections 400, 070 and 004 were obtained by time-resolved X-ray diffractometry in Laue and Bragg geometries. Two saturation processes were observed from the time dependences of the electrical conductivity. A shift in the diffraction peaks and a change in their intensity were found, which indicated a deformation of the crystal structure. Rapid piezoelectric deformation and reversible relaxation-like deformation, kinetically similar to the electrical conductivity of a crystal, were revealed. The deformation depended on the polarity and strength of the applied field. The deformation was more noticeable in the [100] direction and was practically absent in the [001] direction of the applied field. X-ray diffraction analysis revealed a disordered arrangement of potassium atoms, i.e. additional positions and vacancies. The heights of potential barriers between the positions of K+ ions and the paths of their possible migration in the crystal structure of potassium acid phthalate were determined. The data obtained by time-resolved X-ray diffractometry and X-ray structure analysis, along with additional electrophysical measurements, allow the conclusion that the migration of charge carriers (potassium cations) leads to lateral deformation of the crystal structure of potassium phthalate in an external electric field.

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