scholarly journals Dielectric, ferroelectric and optical properties of Na and Nb co-doped (Bi0.5Na0.5)0.94Ba0.06TiO3

2021 ◽  
Vol 22 (4) ◽  
pp. 607-613
Author(s):  
Asif Ali ◽  
Hina Zahid
Keyword(s):  
Optical Properties ◽  
Solid State ◽  
Energy Density ◽  
Room Temperature ◽  
Optical Band Gap ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid State Sintering ◽  
Cubic Structure ◽  
Co Doped

[(Bi0.5Na0.5)0.94Ba0.06]1-xNaTi1-xNbO3 (x = 0.5 and 0.10) ceramics were prepared via conventional solid-state sintering route. X-ray diffraction analysis of the samples exhibited the formation of the cubic structure. Similar structure was observed from the Raman spectra of the samples. The optical band gap of the samples slightly decreased from 3.08 to 3.06 eV with increasing level of Na+ and Nb5+. The addition of Na+ and Nb5+ shifted Tm towards room temperature (RT). The sample x = 0.05 had a stable relative permittivity ɛr(mid) = 3914 across the temperature range 79-350 ℃ and tanδ < 0.025 (104-279 ℃). The energy density of sample with x = 0.05 was 0.4 J/cm3 which decreased to 0.32 J/cm3 at an applied electric field of 50 kV/cm with further substitution of Na+ and Nb5+ (i.e., x = 0.10).

Structural and Optical Properties of Al Co-Doped ZnCoO Thin Film

2014 ◽  
Vol 989-994 ◽  
pp. 656-659
Author(s):  
Ping Cao ◽  
Yue Bai
Keyword(s):  
Thin Film ◽  
Optical Properties ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Al Doping ◽  
X Ray ◽  
Uv Emission ◽  
Uv Absorption Spectroscopy ◽  
Co Doped

Al co-doped ZnCoO thin film has been prepared by a sol-gel method. The structural and optical properties of the sample were investigated. X-ray diffraction and UV absorption spectroscopy analyses indicate that Al3+ and Co2+ substitute for Zn2+ without changing the wurtzite structure. With the Al doping, the visible emission increased and the UV emission decreased, which is attributed to the increase of O vacancies and Zn interstitials.

scholarly journals Structure and electric properties of cerium substituted SrBi1.8Ce0.2Nb2O9 and SrBi1.8Ce0.2Ta2O9 ceramics

2016 ◽  
Vol 10 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Mohamed Afqir ◽  
Amina Tachafine ◽  
Didier Fasquelle ◽  
Mohamed Elaatmani ◽  
Jean-Claude Carru ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Solid State ◽  
Room Temperature ◽  
Single Phase ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Lcr Meter ◽  
Curie Temperature Tc

SrBi1.8Ce0.2Nb2O9 (SBCN) and SrBi1.8Ce0.2Ta2O9 (SBCT) powders were prepared via solid-state reaction method. X-ray diffraction analysis reveals that the SBCN and SBCT powders have the single phase orthorhom-bic Aurivillius structure at room temperature. The contribution of Raman scattering and FTIR spectroscopy of these samples were relatively smooth and resemble each other. The calcined powders were uniaxially pressed and sintered at 1250?C for 8 h to obtaine dense ceramics. Dielectric constant, loss tangent and AC conductivity of the sintered Ce-doped SrBi2Nb2O9 and SrBi2Ta2O9 ceramics were measured by LCR meter. The Ce-doped SBN (SBCN) ceramics have a higher Curie temperature (TC) and dielectric constant at TC (380?C and ?? ~3510) compared to the Ce-doped SBT (SBCT) ceramics (330?C and ?? ~115) when measured at 100Hz. However, the Ce-doped SBT (SBCT) ceramics have lower conductivity and dielectric loss.

X-ray Diffraction Studies of Solid Solutions of Pentaglycerine-Neopentylglycol

1988 ◽  
Vol 32 ◽  
pp. 609-616 ◽  
Author(s):  
D. Chandra ◽  
C. S. Barrett ◽  
D. K. Benson
Keyword(s):  
Crystal Structure ◽  
Energy Storage ◽  
Hydrogen Bonds ◽  
Solid Solutions ◽  
Room Temperature ◽  
Energy Storage Materials ◽  
Anisotropic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cubic Structure

AbstractAn array of molecules that is anisotropic in the extreme has been discovered in certain thermal-energy storage materials and is reported here: neopentylglycol (NPG) and NPG-rich solid solutions with pentaglycerine (PG) have a crystal structure, stable at room temperature, that consists of bimolecular chains of molecules that are all unidirectionally aligned throughout a crystal. There are hydrogen bonds between every molecule in one chain and its neighbors in that chain, but none between molecules of one chain and any molecules of the neighboring parallel chains. Thus there are strong intermolecular bonds along each chain and only weaker bonds between the chains. The structure has been determined by using modern single crystal techniques with 529 independent reflections from a crystal of NPG (C5H12O2). The structure is monoclinic with space group P21/c - C2h5. This anisotropic structure transforms to a cubic structure at higher temperatures.

scholarly journals Impact of Lithium Composition on Structural, Electronic and Optical Properties of Lithium Cobaltite Prepared by Solid-state Reaction

2014 ◽  
Vol 6 (2) ◽  
pp. 217-231 ◽  
Author(s):  
F. Khatun ◽  
M. A. Gafur ◽  
M. S. Ali ◽  
M. S. Islam ◽  
M. A. R. Sarker
Keyword(s):  
Optical Properties ◽  
Solid State ◽  
Ionic Conductivity ◽  
Cathode Material ◽  
Solid State Reaction ◽  
Layered Crystal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electronic And Optical Properties ◽  
Lithium Cobaltite

The lithium-cobalt oxide LixCoO2 is a promising candidate as highly active cathode material of lithium ion rechargeable batteries. The crystalline-layered lithium cobaltite has attracted increased attention due to recent discoveries of some extraordinary properties such as unconventional transport and magnetic properties. Due to layered crystal structure, Li contents (x) in LixCoO2 might play an important role on its interesting properties. LiCoO2 crystalline cathode material was prepared by using solid-state reaction synthesis, and then LixCoO2 (x<1) has been synthesized by deintercalation of produced single-phase powders. Structure and morphology of the synthesized powders were investigated by X-ray diffraction (XRD), Infrared spectroscopy, Impedance analyzer etc. The influence of lithium composition (x) on structural, electronic and optical properties of lithium cobaltite was studied. Temperature dependent electrical resistivity was measured using four-probe technique. While LixCoO2 with x = 0.9 is a semiconductor, the highly Li-deficient phase (0.75 ? x ? 0.5) exhibits metallic conductivity. The ionic conductivity of LixCoO2 (x = 0.5 – 1.15) was measured using impedance spectroscopy and maximum conductivity of Li0.5CoO2 was found to be 6.5×10-6 S/cm at 273 K. The properties that are important for applications, such as ionic conductivity, charge capacity, and optical absorption are observed to increase with Li deficiency. Keywords: Calcination; Characterization; Inorganic compounds; Solid-State reaction; X-ray diffraction. © 2014 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v6i2.17900 J. Sci. Res. 6 (2), 217-231 (2014)  

PHASE STRUCTURE, PIEZOELECTRIC AND MULTIFERRIOC BEHAVIOR OF (K0.48Na0.52)NbO3-Co2O3 PIEZOELECTRIC CERAMICS

2011 ◽  
Vol 04 (03) ◽  
pp. 225-229 ◽  
Author(s):  
WENJUAN WU ◽  
DINGQUAN XIAO ◽  
JIAGANG WU ◽  
JING LI ◽  
JIANGUO ZHU
Keyword(s):  
Room Temperature ◽  
Sintering Temperature ◽  
Magnetic Behavior ◽  
Orthorhombic Phase ◽  
Piezoelectric Ceramics ◽  
X Ray Diffraction ◽  
Two Phase ◽  
X Ray ◽  
Solid State Sintering ◽  
Sintering Method

( K 0.48 Na 0.52) NbO 3-x% Co 2 O 3 (x = 0, 0.03 and 0.05) (KNN-x% Co2O3 ) lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method. An orthorhombic phase was observed for all KNN-x% Co2O3 ceramics at room temperature, and two phase transitions were confirmed by the high temperature X-ray diffraction and the temperature dependence of the dielectric constant. The Co2O3 greatly improves the density and decreases the sintering temperature of KNN ceramics. The KNN-0.05 mol%Co2O3 ceramic exhibits good properties (d33 = 120 pC/N , k p = 0.41, Q m = 213 and T c = 407°C) and a good age stability. The multiferroic behavior was also observed at room temperature for the KNN-0.05 mol%Co2O3 ceramic, as confirmed by P–E loops and magnetic behavior.

Influence of Molecular Conformation on the Solid State Packing of 1,2-Diglycerides Study of 1,2-Dipalmitin and Some Structural Analogs by Electron Diffraction, X-Ray Diffraction, and Infrared Spectroscopy

1978 ◽  
Vol 33 (1-2) ◽  
pp. 39-49 ◽  
Author(s):  
Douglas L. Dorset ◽  
Walter A. Pangborn ◽  
Anthony J. Hancock ◽  
Iris S. Lee
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Room Temperature ◽  
Molecular Conformation ◽  
Crystalline Solid ◽  
X Ray Diffraction ◽  
Chain Packing ◽  
X Ray ◽  
Monoclinic Form ◽  
Extended Chain

Abstract Diffraction studies on natural 1,2-dipalmitin and on analogs, including those based on the configurational isomers of cyclopentane-1,2,3-triol reveal that the 1,2-diglycerides crystallize from solvent with chain methylene packing identical to the monoclinic form of even-chain alkanes. The chains probably are folded back in “hairpin” fashion as found in phospholipid crystal structures. Acyl shifts are observed to occur in the crystalline solid state at room temperature to give the 1,3-diglyceride. Analogs based on the above-mentioned cyclitols show that isomers with adjacent chains trans to the ring (possibly extended chain packing) or with chains cis to the ring (“hair­ pin”) crystallize readily. Both possibly extended chain configurational isomers have the α-form as well as β′-forms and a β-polymorph. The hairpin isomers each give a β′-polymorph but only the all-cts isomer gives an α-form.

Growth and Magneto-Optical Properties of CaTbAlO4 Crystal

2011 ◽  
Vol 306-307 ◽  
pp. 1722-1727 ◽  
Author(s):  
Man Mei ◽  
Li Li Cao ◽  
Yan He ◽  
Ru Ru Zhang ◽  
Fei Yun Guo ◽  
...  
Keyword(s):  
Optical Properties ◽  
Single Crystal ◽  
Room Temperature ◽  
Near Infrared ◽  
Visible Region ◽  
Czochralski Method ◽  
Optical Devices ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectral

The calcium terbium aluminate (CaTbAlO4) single crystal was grown by Czochralski method successfully for the first time.The structure of the crystal was determined by X-ray diffraction analysis.The transmission spectrum of the crystal was measured at room temperature at the wavelength of 400-1500nm.The specific Faraday rotation of the single crystal was surveyed at room temperature at the wavelength 532nm, 633nm, and 1064nm respectively.The Verdet constants of the CaTbAlO4 crystal are calculated and the results show that the Verdet constants of CaTbAlO4 are around 110% higher than that of TGG in the visible and near-infrared spectral region.Therefore,crystal CaTbAlO4 can be promising material for the fabrication of magneto-optical devices in the visible region.

A three-dimensional CdIIcoordination framework: poly[di-μ2-aqua-{μ2-1,4-bis[(1H-1,2,4-triazol-1-yl)methyl]benzene-κ2N4:N4′}di-μ3-terephthalato-κ3O:O′:O′′-dicadmium(II)]

2014 ◽  
Vol 70 (11) ◽  
pp. 1025-1028
Author(s):  
Hong Shen
Keyword(s):  
Solid State ◽  
Thermogravimetric Analysis ◽  
Room Temperature ◽  
Three Dimensional ◽  
Fluorescence Emission ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Strong Fluorescence ◽  
X Ray ◽  
Methyl Benzene

The title CdIIcoordination polymer, [Cd(C10H8O4)(C12H12N6)0.5(H2O)]n, has been obtained by the hydrothermal method and studied by single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, IR spectroscopy and fluorescence spectroscopy. The compound forms a novel three-dimensional framework with 3,8-connected three-dimensional binodal {4.52}2{42.510.612.7.83} topology. An investigation of its photoluminescence properties shows that the compound exhibits a strong fluorescence emission in the solid state at room temperature.

scholarly journals Исследование влияния парциального давления кислорода на фазовый состав наночастиц оксида меди вакуумно-дугового синтеза

2021 ◽  
Vol 91 (12) ◽  
pp. 1984
Author(s):  
А.В. Ушаков ◽  
И.В. Карпов ◽  
Л.Ю. Федоров ◽  
Е.А. Гончарова ◽  
М.В. Брунгардт ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Optical Band Gap ◽  
Arc Discharge ◽  
Copper Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Partial Pressure Of Oxygen ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phase Variations ◽  
Cubic Structure

Copper oxide nanoparticles were obtained in the plasma of a low-pressure arc discharge. The effect of the partial pressure of oxygen (10-40%) on the physical properties of the deposited nanoparticles has been studied. X-ray diffraction analysis shows that the cubic structure of Cu2O changes to monoclinic CuO with increasing O2 pressure. The results of Raman spectroscopy further confirmed the phase variations of copper-based oxide nanoparticles. X-ray photoelectron spectroscopy confirmed the change in the binding energy in the oxidation state of nanoparticles. The optical band gap of the deposited Cu2O is 2.12 eV, while that of CuO is 1.79-1.82 eV.

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