Effect of ZrO2 Doping on Crystal Structure, Microstructure and Phase Transition of Lead Titanate Ceramics

2008 ◽  
Vol 55-57 ◽  
pp. 169-172 ◽  
Author(s):  
Panadda Sittiketkron ◽  
S. Sukkho ◽  
Theerachai Bongkarn
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Lead Titanate ◽  
X Ray ◽  
Zro2 Phase ◽  
Ceramic Samples ◽  
Average Grain Size ◽  
Titanate Ceramics ◽  
Pbtio3 Ceramics ◽  
Scanning Electron

In this work, the effect of ZrO2 doping on the properties of PbTiO3 ceramics was investigated. PbTiO3 powders were prepared via a mixed oxide method with a calcination temperature of 750 °C for 2 h. The various amounts of ZrO2, between 0 and 2 wt.%, were added to the calcined powders to decrease the c/a ratio. The mixed powders were sintered at 1225 °C for 2 h. The samples were characterized using X–ray diffractrometer (XRD), scanning electron microscopy (SEM) and differential scanning calorimeter (DSC). It was showed that the ZrO2 phase was not detected in all of the powder and ceramic samples. The highest density in the ceramics was found in the sample with 0.5 wt.% of ZrO2. The average grain size slightly increased with the increase of ZrO2. The phase transition temperature from tetragonal ferroelectric to cubic paraelectric was about 465 to 466 °C for all sintered samples.

Effect of Excess PbO on Crystal Structure, Microstructure and Phase Transition of Lead Titanate Ceramics

2008 ◽  
Vol 55-57 ◽  
pp. 193-196 ◽  
Author(s):  
W. Tangkawsakul ◽  
Panadda Sittiketkron ◽  
Theerachai Bongkarn
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Lead Titanate ◽  
Raw Materials ◽  
Lead Dioxide ◽  
Average Particle ◽  
Particle Sizes ◽  
Sintering Process ◽  
Sintered Ceramic ◽  
Titanate Ceramics

In this work, we studied the effect of excess PbO on crystal structure, microstructure and phase transition of lead titanate (PT). PT was prepared via a mixed oxide method with various PbO levels (0, 1, 3 and 5 wt.%). The raw materials were calcined at 750 oC for 2 h and sintered at 1225 oC for 2 h. The characteristics of PT were analyzed by a X-ray diffractometer (XRD), scanning electron microscopy (SEM) and differential scanning calorimeter (DSC). It was found that calcined powders and sintered ceramics indexed in a tetragonal structure. For PT powders, the impurity phases of lead oxide (PbO) and lead dioxide (PbO2) were detected in 3 and 5 wt.% of excess PbO samples, but they were not detected in all sintered ceramic samples. The increase of excess PbO levels resulted in a decreased c/a ratio in both calcined powders and sintered ceramics. Average particle sizes increased from 0.64 to 4.24 µm when excess PbO levels increased from 0 to 5 wt.%. It was also clearly seen that the liquid phase of the sintering process was obtained in the PT calcined powders which had an excess of PbO. The DSC result indicated that the phase transition temperature, from a ferroelectric to a paraelectric phase with a high PbO content (5 wt.%), was higher than those with low PbO contents (0, 1 and 3 wt.%).

X-ray powder diffraction data of LaNi0.5Ti0.45Co0.05O3, LaNi0.45Co0.05Ti0.5O3, and LaNi0.5Ti0.5O3 perovskites

2021 ◽  
pp. 1-6
Author(s):  
Mariana M. V. M. Souza ◽  
Alex Maza ◽  
Pablo V. Tuza
Keyword(s):  
Crystal Structure ◽  
Rietveld Method ◽  
Pechini Method ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Modified Pechini Method ◽  
Scanning Electron

In the present work, LaNi0.5Ti0.45Co0.05O3, LaNi0.45Co0.05Ti0.5O3, and LaNi0.5Ti0.5O3 perovskites were synthesized by the modified Pechini method. These materials were characterized using X-ray fluorescence, scanning electron microscopy, and powder X-ray diffraction coupled to the Rietveld method. The crystal structure of these materials is orthorhombic, with space group Pbnm (No 62). The unit-cell parameters are a = 5.535(5) Å, b = 5.527(3) Å, c = 7.819(7) Å, V = 239.2(3) Å3, for the LaNi0.5Ti0.45Co0.05O3, a = 5.538(6) Å, b = 5.528(4) Å, c = 7.825(10) Å, V = 239.5(4) Å3, for the LaNi0.45Co0.05Ti0.5O3, and a = 5.540(2) Å, b = 5.5334(15) Å, c = 7.834(3) Å, V = 240.2(1) Å3, for the LaNi0.5Ti0.5O3.

scholarly journals Ferroelectromagnetic Properties of PbFe1/2Nb1/2O3 (PFN) Material Synthesized by Chemical-Wet Technology

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2504 ◽  
Author(s):  
Dariusz Bochenek ◽  
Przemysław Niemiec
Keyword(s):  
Magnetic Properties ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sintering Temperature ◽  
Closed Porosity ◽  
X Ray ◽  
Synthesis Conditions ◽  
Ceramic Samples ◽  
Sem Microstructure ◽  
Scanning Electron

In this work, PbFe1/2Nb1/2O3 (PFN) ceramic samples synthesized by chemically wet method (precipitation from the solution) were obtained. Due to the tendency to form powder agglomerates, the synthesized powder was subjected to ultrasound. The sintering was carried out under various technological conditions, mainly through controlling the sintering temperature. -X-ray powder-diffraction (XRD), scanning electron microscope (SEM) microstructure analysis, as well as the examinations of dielectric, ferroelectric, and magnetic properties of the PFN ceramics were carried out. Studies have shown that hard ceramic agglomerates can be partially minimized by ultrasound. Due to this treatment, closed porosity decreases, and the ceramic samples have a higher density. Optimization and improvement of the technological process of the PFN material extends the possibility of its use for the preparation of multiferroic composites or multicomponent solid solutions based on PFN. Such materials with functional properties find applications in microelectronic applications, e.g., in systems integrating ferroelectric and magnetic properties in one device. The optimal synthesis conditions of PFN ceramics were determined to be 1050 °C/2 h.

Hydrothermal Synthesis of Lead Titanate Epitaxial Film for Non-Volatile Memory Device Application

2013 ◽  
Vol 652-654 ◽  
pp. 1846-1850
Author(s):  
Thin Thin Thwe ◽  
Than Than Win ◽  
Yin Maung Maung ◽  
Ko Ko Kyaw Soe
Keyword(s):  
Electron Microscopy ◽  
Silicon Dioxide ◽  
Lead Titanate ◽  
Conduction Mechanism ◽  
Epitaxial Film ◽  
Memory Device ◽  
X Ray Diffraction ◽  
X Ray ◽  
Non Volatile Memory ◽  
Scanning Electron

Hydrothermal synthesized lead titanate (PbTiO3¬) powder was prepared in a Teflon-lined stainless steel bomb at different bath temperatures. X-ray diffraction was performed to examine the phase assignment and crystallographic properties of hydrothermal synthesized lead titanate powder. Silicon dioxide (SiO2) was thermally deposited and adapted as intermediate layer on p-Si (100) substrates for MFIS (Metal/Ferroelectric/ Insulator/Semi-conductor) design. The microstructures of PbTiO3 film for both MFS and MFIS designs were observed by scanning electron microscopy (SEM). Charge conduction mechanism was also interpreted by C-2-V relationship. Polarization and electric field characteristics were measured by Sawyer-Tower circuit and good hysteresis nature was formed for both structures of the films. The loop of MFIS was wider than that of MFS cell. Also, the higher value of polarization (Ps=3.21E-03µC/cm2) for MFIS could be explained on the basis of higher dipole moment in this SiO2 buffer layer.

Structure of ammonium hydrogen succinate above and below the phase transition around 170K

1996 ◽  
Vol 52 (2) ◽  
pp. 323-327 ◽  
Author(s):  
A. Hirano ◽  
Y. Kubozono ◽  
H. Maeda ◽  
H. Ishida ◽  
S. Kashino
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Hydrogen Bonds ◽  
Order Phase Transition ◽  
Space Group ◽  
X Ray ◽  
Ammonium Hydrogen ◽  
Significant Change ◽  
Short Hydrogen Bonds ◽  
Second Order Phase Transition

For crystals of ammonium hydrogen succinate it is known that the space group is P{\bar 1} with Z = 2 at 293 K and the second-order phase transition occurs around 170 K. X-ray crystal structure analyses above and below 170 K have been carried out in order to study the change in mode of short hydrogen bonds between the hydrogen succinate ions. The space group was determined to be P{\bar 1} at 150 and 190 K by structure analysis. No ordering of the H-atom positions in the short hydrogen bonds occurs by the phase transition. The hydrogen bonds show a decrease in the O...O distances with a decrease in temperature from 290 to 190 K, but no significant change in the geometries between 190 and 150 K. Disorder of the NH4 + ion is not observed at 297, 190 and 150 K. Significant change through the phase transition is found only in the geometry of one of the N—H...O hydrogen bonds between ammonium and hydrogen succinate ions.

Study on the Properties of Doped La in BaBi4Ti4O15 Ceramic

2007 ◽  
Vol 26-28 ◽  
pp. 243-246
Author(s):  
Xing Hua Yang ◽  
Jin Liang Huang ◽  
Xiao Wang ◽  
Chun Wei Cui
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sintering Temperature ◽  
Solid Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lanthanum Content ◽  
Scanning Electron

BaBi4-xLaxTi4O15 (BBLT) ceramics were prepared by conventional solid phase sintering ceramics processing technology. The crystal structure and the microstructure were detected by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD analyses show that La3+ ions doping did not change the crystal structure of BBT ceramics. The sintering temperature increased from 1120°C to 1150°C with increasing Lanthanum content from 0 to 0.5, but it widened the sintering temperature range from 20°C to 50°C and refined the grain size of the BBT ceramic. Additionally, polarization treatment was performed and finally piezoelectric property was measured. As a result, the piezoelectric constant d33 of the 0.1at.% doped BBLT ceramics reached its highest value about 22pc/N at polarizing electric field of 8kV/mm and polarizing temperature of 120°C for 30min.

SYNTHESIS, MORPHOLOGY AND STRUCTURAL PROPERTIES OF (GD,ND)SR2RUCU2O8 SAMPLES

2003 ◽  
Vol 17 (04n06) ◽  
pp. 899-904 ◽  
Author(s):  
A. VECCHIONE ◽  
M. GOMBOS ◽  
C. TEDESCO ◽  
A. IMMIRZI ◽  
L. MARCHESE ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Solid State ◽  
Powder Diffraction ◽  
Solid State Reaction ◽  
X Ray ◽  
Structure And Morphology ◽  
Polycrystalline Powder ◽  
Scanning Electron

NdSr 2 RuCu 2 O x material has been prepared as polycrystalline powder by solid state reaction. The compound has been investigated by synchrotron x-ray powder diffraction and scanning electron microscopy. The experimental results show that the average crystal structure is a disordered cubic perovskite with Nd and Sr cations occupying the same site and the same substitution is found for Cu and Ru atoms. A comparison between the crystal structure and morphology of this compound and the superconducting tetragonal GdSr 2 RuCu 2 O 8 is also discussed.

Microstructure and Hydrogen Permeability of Duplex Phase M-ZrNi (M=V, Nb, Ta) Alloys

2006 ◽  
Vol 980 ◽  
Author(s):  
Kazuhiro Ishikawa ◽  
Naoshi Kasagami ◽  
Tomoyuki Takano ◽  
Kiyoshi Aoki
Keyword(s):  
Crystal Structure ◽  
Solid Solution ◽  
High Performance ◽  
Gas Flow ◽  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
The Other ◽  
Cast State ◽  
X Ray ◽  
Scanning Electron

AbstractIn order to develop non-Pd based high performance hydrogen permeation alloys, microstructure, crystal structure and hydrogen permeability of duplex phase M-ZrNi (M=V and Ta) alloys were investigated using a scanning electron microscope, an X-ray diffractometer and a gas flow meter. These results were compared with those of Nb-ZrNi ones which have been previously published. The hydrogen permeation was impossible in the V-ZrNi alloys, because they were brittle in the as-cast state. On the other hand, duplex phase alloys consisting of the bcc-(Ta, Zr) solid solution and the orthorhombic ZrNi (Cmcm) intermetallic compound were formed and hydrogen permeable in the Ta-ZrNi system. The Ta40Zr30Ni30 alloy shows the highest value of hydrogen permeability of 4.1×10-8 [molH2m-1s-1Pa-0.5] at 673 K, which is three times higher than that of pure Pd.

High-performance electrical properties of La-based perovskite ceramics for the functional phase of thick film resistors

2020 ◽  
Author(s):  
Yongcheng Lu ◽  
Yuanxun Li ◽  
Daming Chen ◽  
Rui Peng ◽  
Qinghui Yang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electrical Properties ◽  
Thick Film ◽  
High Performance ◽  
Composite Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Alternative Material ◽  
Perovskite Ceramics ◽  
Scanning Electron

Abstract In order to explore an economical functional phase alternative material for thick film resistors, the crystal structure, microstructure, and electrical properties of (1-x)LSCN + xLCNZ (x = 0.0–1.0) composite ceramics were studied through solid-state reaction experiments. The composite ceramics were characterized by x–ray diffraction, scanning electron microscopy, energy dispersive x–ray spectroscopy, and DC four–probe method. Results suggested that the main phases of LSCN and LCNZ were formed, along with a small part of impurity phases. The addition of LCNZ to LSCN decreased the electrical conductivity and changed the TCR from positive to negative. Zero TCR could be achieved around 0.6 < x < 0.8 and relatively low absolute TCR values could be obtained for the samples of 0.4 ≤ x ≤ 0.8. The ceramic of 0.6LSCN + 0.4LCNZ showed the optimal performances of conductivity = 1923 S/cm, TCR = 379.54 ppm/℃, and relative density = 95.05%.

On the Phase Transition of Bis(pyridinium)hexachlorometallates, (C5H5NH)2[MCl6], M = Sn, Te, Pb, Pt. An X-Ray and 35Cl NQR Study

1987 ◽  
Vol 42 (7) ◽  
pp. 739-748 ◽  
Author(s):  
Dirk Borchers ◽  
Alarich Weiss
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Phase Ii ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
X Ray ◽  
Lattice Constants ◽  
Pyridinium Ring ◽  
35Cl Nqr ◽  
Low Temperature Phase

A phase transition has been observed in bis(pyridinium) hexachlorometallates (C5H5NH)2[MIVCl6]. M = Sn. Te. Pb. Pt. The crystal structure of the low temperature phase II of the salt with M = Sn was determined, space group C 1ḷ- P 1̅, Z = 1 (a = 734.1pm, b = 799.0 pm, c = 799.7 pm,α= 83.229°. β = 65.377°, γ= 84.387°, T = 297 K). The four compounds are isotypic in phase II as well as in the high temperature phase I (C2H2-B2 /m, Z = 2) for which the crystal structure is known for M = Te . The lattice constants of all compounds (both phases) are given. The temperature dependence of the 35Cl NQR spectrum was investigated. The three line 35Cl NQR spectrum is in agreement with the crystal structure. The dynamics of the pyridinium ring shows up in a fade out of part of the 35Cl NQR spectrum . The influence o f H ↔ D exchange on 35Cl NQR is studied and an assignment of ν (35Cl) ↔ Cl(i) is proposed. The nature of the phase transition P1̅ (Z = 1) ↔ B2 /m (Z = 2) is discussed.

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