Dielectric and Raman studies of Ba0.06(Na1/2Bi1/2)0.94TiO3–NaNbO3 ceramics

AbstractIn this work the X-ray diffraction, scanning electron microscopy, Raman and dielectric studies of lead free perovskite (1 – x)Ba0.06(Na1/2Bi1/2)0.94TiO3–xNaNbO3 (0 ⩽ x ⩽ 1.0) ceramics, prepared using a standard solid state reaction method, were investigated. X-ray diffraction studies of all the ceramics suggested the formation of single phase with crystal structure transforming from rhombohedral-tetragonal to orthorhombic symmetry with the increase in NaNbO3 content. Raman spectra also confirmed the formation of solid solution without any new phase. Dielectric studies showed that the phase transition is of diffusive character and diffusivity parameter decreases with increasing NaNbO3 content. The compositional fluctuation was considered to be the main cause of diffusivity.

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Effect of Zr addition on structure and electrical properties of SmFeO3 prepared by solid state reaction method

Processing and Application of Ceramics ◽

10.2298/pac1704275a ◽

2017 ◽

Vol 11 (4) ◽

pp. 275-281 ◽

Cited By ~ 4

Author(s):

Abdalla Abdalla ◽

Shahzad Hossain ◽

Pg. Petra ◽

Abul Azad

Keyword(s):

Solid State ◽

Solid State Reaction ◽

Single Phase ◽

Solid State Reaction Method ◽

Orthorhombic Symmetry ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Zr Addition ◽

Pbnm Space Group

Series of Sm1-xFe1-3xZr3xO3 (SFZO, where x = 0.0, 0.01, 0.02, 0.033, 0.05, 0.1 and 0.15), was synthesised by the solid state reaction method and sintered at 1500?C in air. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate the structure of the materials. The XRD results indicated that the pure SmFeO3 and Sm0.99Fe0.97Zr0.03O3 samples are single phase materials with an orthorhombic symmetry and Pbnm space group. The increase of Zr content (x ? 0.02) causes a phase change from single to twophase system with orthorhombic (Pbnm) and fluorite symmetry (Fm?3m). The microstructural analyses showed that the Zr4+ doping resulted in an increase of porosity in the sintered SFZO compared to SmFeO3 sample. The direct current (DC) electrical conductivity at 850?C in air was found to be 0.045 S/cm and 0.007 S/cm for Sm0.99Fe0.97Zr0.03O3 and SmFeO3, respectively, showing a significant enhancement compared to the pure SmFeO3.

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

Processing and Application of Ceramics ◽

10.2298/pac1603183a ◽

2016 ◽

Vol 10 (3) ◽

pp. 183-188 ◽

Cited By ~ 5

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.

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Luminescence Properties of Self-Activated M3(VO4)2 (M = Mg, Ca, Sr, and Ba) Phosphors Synthesized by Solid-State Reaction Method

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11825 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3684-3689 ◽

Cited By ~ 11

Author(s):

Xin Min ◽

Zhaohui Huang ◽

Minghao Fang ◽

Yan’gai Liu ◽

Chao Tang ◽

...

Keyword(s):

Solid State ◽

Solid State Reaction ◽

Single Phase ◽

Uv Light ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Light Emitting ◽

Reaction Method ◽

X Ray ◽

Yield Decrease

In this paper, M3(VO4)2 (M = Mg, Ca, Sr, and Ba) self-activated phosphors were prepared by a solid-state reaction method at 1,000 °C for 5 h. The phase formation and micrographs were analyzed by X-ray diffraction and scanning electron microscopy. The Ca3(VO4)2 phosphor does not show any emission peaks under excitation with ultraviolet (UV) light. However, the M3(VO4)2 (M = Mg, Sr, and Ba) samples are effectively excited by UV light chips ranging from 200 nm to 400 nm and exhibit broad emission bands due to the charge transfer from the oxygen 2p orbital to the vacant 3d orbital of the vanadium in the VO4. The color of these phosphors changes from yellow to light blue via blue-green with increasing ionic radius from Mg to Sr to Ba. The luminescence lifetimes and quantum yield decrease with the increasing unit cell volume and V–V distance, in the order of Mg3(VO4)2 to Sr3(VO4)2 to Ba3(VO4)2. The emission intensity decreases with the increase of temperatures, but presents no color shift. This confirms that these self-activated M3(VO4)2 phosphors can be suggested as candidates of the single-phase phosphors for light using UV light emitting diodes (LEDs).

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Thermoelectric properties of LaFeO3 system with doped Ti, Co, Cu

HUE UNIVERSITY JOURNAL OF SCIENCE NATURAL SCIENCE ◽

10.26459/hueuni-jns.v126i1b.4155 ◽

2017 ◽

Vol 126 (1B) ◽

pp. 147

Author(s):

Nguyen Thi Thuy

Keyword(s):

Electron Microscope ◽

Solid State ◽

Room Temperature ◽

Unit Cell Volume ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Scanning Electron

Abstract: LaFeO3 system with doped Ti, Co, Cu was manufactured by solid state reaction method, it was sintered at 12500C and 12900C in 10 hours with a heating rate of 30C/min. Using X-ray diffraction and Scanning Electron Microscope (SEM) to examine the structure, it reveals that samples are single-phase and orthogonal-perovskite structure describing by the Pnma space group, the unit cell volume of the samples increases when Ti, Co, Cu are doped to replace ion Fe+3. The size of particle increase while raising the temperature of sintering. Measuring the resistance which depends on temperature between the room temperature and 1000K, it can be seen that when doping Co, Cu with the nominal component La(Fe0,2Co0,2Ti0,6)O3 and La(Fe0,4Cu0,1Ti0,5)O3 , the conductivity of samples increases respectively. Especially, the conductivity of Cu doped sample is higher than two other samples, and reach the highest conductivity at about 9000C, Seebeck coefficient S of La(Fe0.6Ti0.4)O3 can be change from positive to negative at the temperature of around 7000C.

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Influence of Mg and B Stoichiometry on the Formation Behavior of MgB2 Phase

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.2035 ◽

2007 ◽

Vol 546-549 ◽

pp. 2035-2039 ◽

Cited By ~ 1

Author(s):

S.C. Yan ◽

G. Yan ◽

Ya Feng Lu ◽

Y. Feng ◽

Lian Zhou

Keyword(s):

Single Phase ◽

Solid State Reaction Method ◽

Stable Phase ◽

Superconducting Transition ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Formation Behavior ◽

Mg Addition ◽

Mgb2 Phase

Bulk samples with the stoichiometry of Mg:B=1:2 and 1:4 were prepared by solid state reaction method. The microstructure and constituent of the samples were investigated by using the scanning electron microscope (SEM) and the x-ray diffraction (XRD). XRD results showed that the MgB2 phase was first formed in all the samples with different stoichiometry of Mg and B, which indicated that the MgB2 was the most thermodynamically stable phase in the Mg-B binary system. For the samples of Mg:B=1:2, the MgB2 single phase was formed very well when these samples were sintered at 650°C~700°C. For the samples with later added Mg reaching to the stoichiometry of Mg:B=1:2, a longer reaction time or higher reaction temperature was required for the formation of the MgB2 single phase. The SEM results showed that the samples with later added Mg had dense microstructures, suggesting that the later addition of Mg could reduce the porosity of the sample. A small increase of the superconducting transition temperature, Tc, in the Mg addition sample resulted from the dense microstructures.

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Synthesis of Vanadium (III) Doped Anatase TiO2 by Solid State Reaction Method

ALCHEMY ◽

10.18860/al.v5i1.3739 ◽

2018 ◽

Vol 5 (1) ◽

pp. 26

Author(s):

Nur Aini ◽

Rachamawati Ningsih

Keyword(s):

Solid State ◽

Visible Light ◽

Solid State Reaction ◽

Single Phase ◽

Diffuse Reflectance Spectroscopy ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Vanadium Doping

Anatase of Titanium dioxide (TiO2) was doped with vanadium ions (V3+), at doping levels ranging from 0.3, 0.5 to 0.7 atomic percentage in order to increase its photocatalytic activity under visible light irradiation. Vanadium doped TiO2 was synthesized by solid state reaction method. Its physicochemical properties characterized by powder X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectroscopy (DRS). Doping with V(III) resulted in a single phase structure of anatase TiO2 with nanosize crystal ranging from 53.06 to 59.59 nm. Vanadium doping also resulted in a red-shift of the photophysical response of TiO2 that was reflected in an extended absorption in the visible light between 400 and 700 nm.

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Magnetic and electronic properties of M-Ba–Cu–O (M = Y, Er, Eu)

Journal of Materials Research ◽

10.1557/jmr.1987.0775 ◽

1987 ◽

Vol 2 (6) ◽

pp. 775-778 ◽

Cited By ~ 6

Author(s):

H. Jenny ◽

B. Walz ◽

G. Leeman ◽

V. Geiser ◽

S. Jost ◽

...

Keyword(s):

Electrical Resistivity ◽

Photoelectron Spectroscopy ◽

Room Temperature ◽

Single Phase ◽

Liquid Nitrogen Temperature ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Diffraction Peaks

Various high-Tc superconductors of the La–(Ba,Sr)–Cu–O and the M–Ba–Cu–O systems with M = Y, Er, and Eu have been prepared by the solid-state reaction method. Single-phase samples with no additional diffraction peaks as verified by x-ray diffraction (XRD) measurements have been obtained. Measurements of the electrical resistivity and of the magnetization showed sharp superconducting transitions with a width of 1 K. The measurements of the magnetic susceptibility have been extended above room temperature up to 770 K. There is clear evidence for the formation of a magnetic moment in all M–Ba–Cu–O samples. Monochromated x-ray photoelectron spectroscopy (MXPS) valence band and x-ray photoelectron spectroscopy (XPS) core level spectra have been measured on various samples at room temperature and at liquid nitrogen temperature.

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Effects of Cu Doping on the Microstructure and Electrical Properties of Sr3YCo4O10.5+δ Polycrystalline

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.934.80 ◽

2014 ◽

Vol 934 ◽

pp. 80-85

Author(s):

Xiao Li Du ◽

Lan Yu ◽

Bin Zhang ◽

Shi Jin Song ◽

Guo Fang Li

Keyword(s):

Porous Structure ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Cu Doping ◽

Reaction Method ◽

X Ray ◽

Cu Content ◽

Grain Sizes ◽

Liquid Sintering

Polycrystalline samples of Sr3YCo4-xCuxO10.5+δ (x=0, 0.2, 0.4, 0.6) have been prepared by solid state reaction method. Crystal structure has been checked by X-ray diffraction (XRD) and the results indicate that Sr3YCo4-xCuxO10.5+δ (x=0, 0.2, 0.4) with single phase have been synthesized in air, and the lattice parameters of Sr3YCo4-xCuxO10.5+δ (x=0, 0.2, 0.4) increase with increasing Cu content. Microstructure analysis demonstrates that the grain sizes enlarge and the number of pores decreases with increasing Cu content. The change of porous structure with different Cu contents is discussed by the liquid sintering theory. The temperature dependence of resistivity (ρ-T) curves of Sr3YCo4-xCuxO10.5+δ show nonmetallic behavior. And the electrical resistivity decreases successively with increasing Cu content, which is caused by the porous structure scattering the carriers as well as the increase of hole carriers.

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Effect of Co-Ti Substitution on Magnetic Properties of Nanocrystalline BaFe12O19

KnE Engineering ◽

10.18502/keg.v0i0.506 ◽

2016 ◽

Vol 1 (1) ◽

Author(s):

Erfan Handoko

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Polycrystalline Structure ◽

Reaction Method ◽

X Ray ◽

Ti Substitution ◽

Scanning Electron ◽

Microstructure And Magnetic Properties

The synthesis of nanocrystalline BaFe12-2xCoxTixO19 with variations of x (x = 0, 1, 2, and 3) have been investigated. The formation of polycrystalline samples that the cationic of Co2+ and Ti4+ in Co-Ti substituted Fe in BaFe12O19 ferrites structure were prepared by solid state reaction method. The crystal structure, microstructure, and magnetic properties were characterized using powder X-ray diﬀraction, scanning electron microscope (SEM) and permagraph meter, respectively. The results show that the nanocrystalline BaFe12-2xCoxTixO19 has single phase with polycrystalline structure, the grain size decrease by doping, the coercivity (Hc) and saturation magnetization (Ms) decrease with increasing Co-Ti substitutions.

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Synthesis and Dielectric Properties of Ba(Ti,Y)O3 Solid Solutions to Ba3Ti2YO8.5-BaTiO3 Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.109 ◽

2011 ◽

Vol 194-196 ◽

pp. 109-112

Author(s):

Min Huang ◽

Yun Wu Wang

Keyword(s):

Single Phase ◽

Xrd Analysis ◽

Solid State Reaction Method ◽

Nominal Composition ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Microstructure Observation ◽

Ceramic Samples ◽

Scanning Electron

Ceramic samples with the nominal composition (1-x) BaTiO3 + x Ba3Ti2YO8.5 (x = 0 - 0.4) were prepared by the solid-state reaction method. The X-ray diffraction (XRD) analysis and the lattice parameters determination indicate that the samples with x≤ 0.16 exhibit a single phase cubic perovskite structure. When x > 0.16, the system is of biphasic composites, which consist of Ba(Ti0.911Y0.089)O3 and Ba3Ti2YO8.5. The microstructure observation by Scanning Electron Microscopy (SEM) supports the XRD result. For the biphasic composites, the dielectric constant follows the Lichtenecker relation in a wide temperature range.

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