Pb-DOPING EFFECTS ON THE DIELECTRIC AND PYROELECTRIC PROPERTIES OF (Sr,Pb)TiO3 SYSTEM

2012 ◽  
Vol 02 (01) ◽  
pp. 1250005 ◽  
Author(s):  
Y. P. JIANG ◽  
X. G. TANG ◽  
Y. C. ZHOU ◽  
Q. X. LIU
Keyword(s):  
Dielectric Permittivity ◽  
Frequency Dispersion ◽  
X Ray Diffraction ◽  
Pyroelectric Properties ◽  
Doping Effects ◽  
Pyroelectric Sensors ◽  
Diffraction Patterns ◽  
Perovskite Type ◽  
Pb Doping ◽  
Perovskite Type Structure

Lead strontium titanate ( Sr 1-x Pb x) TiO 3 (0.20 ≤ x ≤ 0.45,step = 0.05) ceramics were prepared by conventional mixed oxide method. The X-ray diffraction patterns indicate that the prepared samples have perovskite-type structure. With the increase of Pb content, there is a tendency from the cubic to tetragonal structure. The scanning electron microscopy micrographs reveal that the addition of Pb can affect microstructure. The dependent temperature dielectric permittivity and dielectric loss were investigated in the frequency range from 100 Hz to 1 MHz. The maximum peak of the dielectric permittivity versus temperature curve was broadened and a frequency dispersion of the dielectric permittivity was observed for the (Sr0.8Pb0.2)TiO3 ceramics. The results obtained at the frequency of 10 kHz reveal the Curie temperature linearly increased with the lead content. The fitted curves of temperature versus inverse dielectric permittivity at 10 kHz for ( Sr 1-x Pb x) TiO3 ceramics are consistent with Curie–Weiss law. The Pyroelectric properties were also investigated. The high pyroelectric coefficients and figure of merits indicate that the SPT ceramics are potential materials for pyroelectric sensors.

Structure analysis of CaTi1−xSnxO3 (x = 0.0–1.0) solid solutions

2014 ◽  
Vol 29 (3) ◽  
pp. 254-259 ◽  
Author(s):  
Naoki Takani ◽  
Hisanori Yamane
Keyword(s):  
Solid State ◽  
Solid Solutions ◽  
Solid State Reaction ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Patterns ◽  
Perovskite Type ◽  
Perovskite Type Structure

CaTi1−xSnxO3 (x = 0.0–1.0) solid solutions were prepared by solid-state reaction at 1450 °C. Rietveld refinement of their powder X-ray diffraction patterns revealed that all the solid solutions crystallized in orthorhombic cells with the perovskite-type structure, the space group Pbnm. The refined unit-cell parameters linearly increased with nominal tin contents x.

Effects of Calcination Parameters on the Microstructure and Morphology of PZT Nanoparticles Prepared by Modified Sol–Gel Method

2012 ◽  
Vol 576 ◽  
pp. 326-329 ◽  
Author(s):  
Amid Shakeri ◽  
Hossein Abdizadeh ◽  
Mohammad Reza Golobostanfard
Keyword(s):  
Lead Zirconate Titanate ◽  
Sol Gel ◽  
Lead Zirconate ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Treatment Conditions ◽  
Perovskite Type ◽  
Perovskite Type Structure

Lead zirconate titanate nanopowder Pb(Zr0.53Ti0.47)O3 (PZT) was prepared by modified sol-gel method with 1-propanol as solvent and acetylacetone as stabilizer. The microstructure and particle size measurements at different heat treatment conditions were characterized by field emission scanning electron microscopy and x-ray diffraction analysis. It was found that the PZT nanoparticles calcinated at 600 °C showed mean diameter of 75-125 nm with high crystallinity of perovskite-type structure.

scholarly journals Получение, структура, диэлектрические и магнитные свойства керамики SrFe-=SUB=-2/3-=/SUB=-W-=SUB=-1/3-=/SUB=-O-=SUB=-3-=/SUB=-

2018 ◽  
Vol 60 (3) ◽  
pp. 510
Author(s):  
А.В. Павленко ◽  
А.В. Турик ◽  
Л.А. Шилкина ◽  
С.П. Кубрин ◽  
Ю.B. Русалев ◽  
...  
Keyword(s):  
Room Temperature ◽  
Single Phase ◽  
Solid Phase ◽  
Ceramic Technology ◽  
Tetragonal Symmetry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid Phase Reactions ◽  
Perovskite Type ◽  
Perovskite Type Structure

AbstractPolycrystalline samples of SrFe_2/3W_1/3O_3 (SFWO) ceramic were obtained by solid-phase reactions with subsequent sintering using conventional ceramic technology. X-ray diffraction analysis showed that at room temperature, the SFWO ceramic is single-phase and has a perovskite-type structure with tetragonal symmetry and parameters a = 3.941(9) Å, c = 3.955(6) Å, and c/a = 1.0035. In studying the magnetic properties and the Mössbauer effect in SFWO ceramics, it is found that the material is a ferrimagnet, and the iron ions are only in the valence state of Fe^3+. It is suggested that in the temperature range of T = 150–210°C, a smeared phase transition from a cubic (paraelectric) phase to a tetragonal (ferroelectric) phase takes place in SFWO with decreasing temperature.

X-ray powder diffraction data for Mn4C

2019 ◽  
Vol 34 (2) ◽  
pp. 196-197
Author(s):  
Ping-Zhan Si ◽  
Jung Tae Lim ◽  
Jihoon Park ◽  
Chul-Jin Choi
Keyword(s):  
Diffraction Data ◽  
Unit Cell Volume ◽  
Unit Cell ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Perovskite Type ◽  
Perovskite Type Structure

We report on the X-ray diffraction data and unit-cell parameters of Mn4C, which has a cubic perovskite-type structure with a = 3.8726 Å and unit-cell volume V = 58.1 Å3. The measured lines were indexed and are consistent with the space group $ Pm { \bar {\it 3}} m$ (No. 221).

Effect of thermoelectric material of Ca or Fe-doped LaCoO3

2018 ◽  
Vol 32 (19) ◽  
pp. 1840037
Author(s):  
Kei-Ichiro Murai ◽  
Shuhei Kori ◽  
Shun Nakai ◽  
Toshihiro Moriga
Keyword(s):  
Figure Of Merit ◽  
Solid Phase ◽  
X Ray Diffraction ◽  
Lanthanum Cobaltite ◽  
Iron Doped ◽  
Calcium Doped ◽  
Diffraction Patterns ◽  
Lanthanum Cobalt Oxide ◽  
Perovskite Type ◽  
Fe Substitution

As the Perovskite-type Lanthanum Cobalt Oxide of LaCoO3 is nontoxic and thermally stable even at high temperature, this material is expected as a candidate for thermoelectric applications. The thermoelectric performance of a material is often evaluated by the dimensionless figure-of-merit, ZT (=S[Formula: see text]T/[Formula: see text]), or S[Formula: see text] in the ZT equation. S[Formula: see text] shows the electrical characteristic as a Power factor (PF). It has been reported Seebeck coefficient of LaCoO3 is higher than other oxide materials at room temperature even though electrical conductivity and ZT are lower values. In this study, calcium-doped lanthanum cobaltite La[Formula: see text]Ca[Formula: see text]CoO3 (x = 0.00, 0.05, 0.10 and 0.15) and iron-doped lanthanum cobaltite LaCo[Formula: see text]Fe[Formula: see text]O3 (y = 0.05, 0.10 and 0.15) have been prepared by solid-phase process. The X-ray diffraction patterns of the calcium-doped samples and iron-doped samples show cubic perovskite structure. Electric conductivities were improved by Ca or Fe substitution and showed a tendency to increase with increasing the temperature. The sample substituted with Fe 5 mol.% showed the maximum PF, 0.510 ([Formula: see text] W/K2m) at 548 K, and the sample substituted with Ca 15 mol.% showed the maximum PF, 0.152 ([Formula: see text] W/K2m) at 498 K.

scholarly journals Removal of Methyl Violet from Aqueous Solutions Using the A Site Doped Perovskite +-Oxides BaxSr3-xNbO5.5 (x=0, 1 and 2)

2020 ◽  
Vol 3 (1) ◽  
pp. 23-31
Author(s):  
Labib. A. Awin ◽  
Mahmoud. A. El-Rais ◽  
Abdunnaser M Etorki ◽  
Moda. M. Ezrgane
Keyword(s):  
Aqueous Solutions ◽  
Crystal Size ◽  
Methyl Violet ◽  
X Ray Diffraction ◽  
Removal Capacity ◽  
Three Samples ◽  
A Site ◽  
Perovskite Type ◽  
Perovskite Type Structure ◽  
Maximum Removal

Three members of the A- site doped Nb perovskites with general formula Sr3NbO5.5, BaSr2NbO5.5 and Ba2SrNbO5.5 were synthesised by solid-state methods and their removal efficiency of Methyl violet from aqueous solutions investigated. The X-ray diffraction measurements demonstrated that the three samples have a faced cubic perovskite-type structure in space group Fm m. The addition of Ba2+ into the A-site of Sr3NbO5.5 has influenced the cell volume, crystal size and density. Subsequently, the removal capacity was also impacted. The crystallite size of the oxides was determined to be less than 82 nm. The maximum removal capacities of Methyl violet are found to be 46.5, 13.1 and 8.0 mg/g using Ba2SrNbO5.5, BaSr2NbO5.5 and Sr3NbO5.5 respectively. The amounts of the dye adsorbed by the oxides have increased as the Ba2+ content increased. The removals of Methyl violet have positive relationship with pH, temperature and the mass of the oxides.

scholarly journals INTERACTION OF LANTHANE AND LUTETIUM AT TEMPERATURE 1500–1600°C

2020 ◽  
Vol 86 (3) ◽  
pp. 19-25
Author(s):  
Olga Chudinovych ◽  
Nataliya Zhdanyuk
Keyword(s):  
Systematic Study ◽  
Composition Range ◽  
Phase Relationship ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Wide Range ◽  
Concentration Dependences ◽  
Perovskite Type ◽  
Perovskite Type Structure

Materials based on La2O3–Lu2O3 system are promising candidates for a wide range of applications, but the phase relationship has not been studied systematically previously. To address this challenge, the subsection of the phase diagram for 1500 and 1600 °C have been elucidated. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying and heat treatment at 1100, 1500 and 1600 °C. The phase relations in the binary La2O3–Lu2O3 system at 1500 and 1600 °C were studied from the heat treated samples using X-ray diffraction analysis and scanning electron microscopy in the overall concentration range. The X–ray analysis of the samples was performed by powder method using DRON-3 at room temperature (CuKa radiation). It was established that in the binary La2O3–Lu2O3 system there exist fields of solid solutions based on hexagonal (A) modification of La2O3, cubic (C) modification of Lu2O3, and with perovskite–type structure of LaLuO3 (R) with rhombic distortions. The systematic study that covered whole composition range excluded formation of new phases. The systematic study that covered whole composition range excluded formation of new phases. The boundaries of mutual solubility and concentration dependences the lattice parameters for all phases have been determined. The solubility of Lu2O3 in the hexagonal А–lanthanum modification is ~ 9 mol. % at 1500 and 1600 °С. The solubility of La2O3 in the cubic C–Lu2O3 is ~ 4 mol. % at 1500 and 7 mol. % at 1600 °С.

Photoluminescence of Nanocrystalline Bismuth Titanate Thin Films Synthesized by the Sol-Gel Method

2006 ◽  
Vol 514-516 ◽  
pp. 128-132 ◽  
Author(s):  
Agata Lisińska-Czekaj ◽  
M. Czaja ◽  
Lucjan Kozielski ◽  
Dionizy Czekaj ◽  
M. Piechowiak ◽  
...  
Keyword(s):  
Thin Films ◽  
Bismuth Titanate ◽  
Sol Gel ◽  
Diffraction Method ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Sol Gel Process ◽  
Uv Luminescence ◽  
Perovskite Type ◽  
Perovskite Type Structure

The present study is devoted to synthesis and investigation of photoluminescence in the nanosized Bi4Ti3O12 (BTO) thin films. The randomly oriented BTO thin films have been obtained by a modified hybrid sol-gel process. Bismuth nitrate and titanium (IV) butoxide were used as the starting materials. The thin films were deposited on silicon, glass and stainless steel by spin coating and crystallized by the conventional thermal annealing at temperature T=650°C. Formation of the layer perovskite-type structure of the orthorhombic symmetry was confirmed by X-ray diffraction method. Conservation of the chemical composition was investigated by energy dispersive spectroscopy. The UV luminescence has been observed in BTO thin films at room temperature. Results on luminescence excitation and emission in bismuth titanate thin films are given in the present paper.

scholarly journals Nonstoichiometry Effects in SrTiO3 Ceramics Assessed by Transmission Electron Microscopy

2008 ◽  
Vol 14 (S3) ◽  
pp. 5-6 ◽  
Author(s):  
L. Amaral ◽  
A.M.R. Senos ◽  
P.M. Vilarinho
Keyword(s):  
Grain Size ◽  
Electrical Properties ◽  
Dielectric Permittivity ◽  
Grain Boundaries ◽  
Small Variation ◽  
Sintered Ceramic ◽  
Transmission Electron ◽  
Perovskite Type ◽  
Srtio3 Ceramics ◽  
Perovskite Type Structure

Strontium titanate (SrTiO3, ST) has a perovskite type structure that is cubic at room temperature, but transforms into a tetragonal one at 105K. At very low temperatures, ST exhibits an extremely large dielectric permittivity and piezoelectric and superconducting characteristics. ST finds applications in tunable microwave devices, due to a dependence of its dielectric response on the electric field and low microwave losses. ST electrical properties are strongly dependent on grain boundaries features and directly influenced by grain size distribution. It was found in our previous studies that a small variation in the stoichiometry of ST has a significant effect on the grain size of the sintered ceramic and related electrical properties: increased grain size and dielectric permittivity values have been reported for Ti excess compositions whereas Sr excess caused a decrease of grain size and of the dielectric permittivity. The tailoring of the dielectric properties by small non-stoichiometric variations in ST needs, however, a full understanding of its effects on the microstructure, phases structure and on the structure / composition of the grain boundaries.

Sign in / Sign up

Export Citation Format

Share Document