scholarly journals Processing and dielectric properties of ZnTiO3 ceramics prepared from nanopowder synthesised by sol-gel technique

2012 ◽  
Vol 6 (2) ◽  
pp. 83-89 ◽  
Author(s):  
Ahcéne Chaouchi ◽  
Malika Saidi ◽  
Sophie D’astorg ◽  
Sylvain Marinel
Keyword(s):  
Dielectric Properties ◽  
Sol Gel ◽  
Milled Powder ◽  
X Ray Diffraction ◽  
Dielectric Characteristics ◽  
Copper Electrodes ◽  
Crystallite Sizes ◽  
Dta Analysis ◽  
Gel Technique ◽  
Zntio3 Ceramics

ZnTiO3 nanopowders were obtained by sol-gel method. The nanopowders were characterised by means of TGA/DTA analysis, X-ray diffraction, TMA analysis and SEM characterisation. The results show that the crystalline structure of the sol-gel powders was obtained at 600?C, with crystallite sizes of 10 nm. SEM shows that most of the prepared ZnTiO3 nanopowders are agglomerated. Since agglomeration plays an important role in the sintering of the ZnTiO3 ceramics, different deagglomeration techniques (ultrasonication, pulverisation and attrition milling) were investigated. Dense ZnTiO3 structure was obtained from the attrition milled powder at 1050?C and its dielectric characteristics were also investigated (?r =25, t?= -26 ppm/?C and tg? < 10-3 at 1 MHz). The low sintering temperature and the good dielectric properties show promise for the manufacture of multilayered capacitors with internal copper electrodes.

Antimicrobial Activity of Ga-Doped Hydroxyapatite Nanostructures: Synthesis, Morphological, Spectroscopic, and Dielectric Properties

2019 ◽  
Vol 9 (7) ◽  
pp. 881-889 ◽  
Author(s):  
Obaid Albulym ◽  
Omer Kaygili ◽  
Mai S. A. Hussien ◽  
H. Y. Zahran ◽  
Mona Kilany ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Sol Gel ◽  
Alternating Current ◽  
Inhibitory Effect ◽  
X Ray Diffraction ◽  
Carbonate Group ◽  
Ftir Technique ◽  
Gel Technique ◽  
Ga Content ◽  
Ft Raman

In the present paper, seven samples of hydroxyapatite (HAp) nanoparticles doped with different amounts (e.g., 0%, 1%, 3%, 6%, 9%, 12%, and 15% [wt.]) of Ga-ions were synthesized at low temperature using the microwave-assisted sol–gel technique. FT-Raman/Fourier-transform infrared (FTIR) technique, X-ray diffraction (XRD), dielectric/alternating current conductivity measurements, scanning electron microscopy, and antimicrobial tests were utilized in order to characterize the synthesized samples. The Ga content was observed to affect the crystallite size as well as the crystallinity of HAp. Variations were observed in the lattice parameters, lattice strain, and dislocation density. FTIR analysis revealed that HAp structure possessed the carbonate group. Thus all samples have promising medical applications, as this group improves the bioactivity of HAp. Dielectric properties, as well as the alternating current electrical conductivity, were also observed to be affected by the Ga content. Furthermore, the present study demonstrated that the Ga-doped HAp nanostructures exerted a considerable inhibitory effect on bacteria (Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli) and fungi (Candida albicans). Therefore, the Gadoped HAp nanostructures are proposed as a promising candidate for applications in the field of bone cement engineering.

Structure and Characteristics of ZrO2 Dielectric Thin Films by Sol-Gel Technique

2014 ◽  
Vol 602-603 ◽  
pp. 767-770 ◽  
Author(s):  
Ching Fang Tseng ◽  
Chiu Yun Chen ◽  
Pei Wen Huang
Keyword(s):  
Thin Films ◽  
Dielectric Properties ◽  
Annealing Temperature ◽  
Substrate Surface ◽  
Sol Gel ◽  
Dielectric Thin Films ◽  
Dielectric Characteristics ◽  
Impedance Analyzer ◽  
Annealing Temperatures ◽  
Gel Technique

Dielectric properties and microstructures of ZrO2thin films prepared by the sol-gel method at different annealing temperatures have been investigated. All films exhibited ZrO2(111) highly orientation perpendicular to the substrate surface and the grain size increased with increasing annealing temperature. Dielectric properties of the Ag/ZrO2/Ag/Si structure were measured by using HP 4192 Impedance Analyzer and Agilent 4155 Semiconductor Parameter Analyzer. The dependence of the microstructure and dielectric characteristics on annealing temperature was also investigated.

STRUCTURE AND DIELECTRIC PROPERTIES OF La-DOPED LEAD STRONTIUM TITANATE THIN FILMS DERIVED FROM SOL–GEL METHOD

2008 ◽  
Vol 15 (01n02) ◽  
pp. 13-18
Author(s):  
X. T. LI ◽  
C. WU ◽  
W. J. WENG ◽  
G. R. HAN ◽  
P. Y. DU
Keyword(s):  
Thin Films ◽  
Dielectric Properties ◽  
Perovskite Phase ◽  
Sol Gel ◽  
Dielectric Constants ◽  
X Ray Diffraction ◽  
Glass Substrates ◽  
Ito Glass ◽  
Gel Technique ◽  
La Doped

A series of ( Pb 0.4 Sr 0.6)1-x La 2x/3 TiO 3 (PSLT) thin films were deposited on ITO/glass substrates by sol–gel technique. Their phase status, surface morphology, and dielectric properties were studied by X-ray diffraction, scanning electron microscope, and impedance analyzer, respectively. Results show that the PSLT thin films were consisted of tetragonal perovskite phase PSLT thin films for x < 0.4, and cubic perovskite phase PSLT thin films for x > 0.4. Dielectric properties such as dielectric constants, dielectric tunabilitis, and inharmonic coefficient were characterized as a function of the film composition.

scholarly journals Effect of Eu3+ Concentration on the BaAl2O4/CaAl4O7: x% Eu3+ (0 ≤ x ≤ 5.5) Mixed-Phase Nanophosphors Synthesized Using Citrate Sol-Gel Method

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Bamba Mahman ◽  
Mpho Enoch Sithole
Keyword(s):  
Electron Microscopy ◽  
Sol Gel ◽  
Mixed Phase ◽  
Nanometer Scale ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Structure Morphology ◽  
Crystallite Sizes ◽  
Gel Technique

A series of undoped mixed-phase BaAl2O4/CaAl4O7 (hereafter called BC) and doped BC: x% Eu3+ (0 < x ≤ 5.5) nanophosphors were successfully prepared by the citrate sol-gel technique. Their structure, morphology, and optical properties were studied in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy. XRD and SEM showed that all the BC:x% Eu3+ samples consisted of the crystalline structure of the mixed phases of both the BaAl2O4 and CaAl4O7 materials. The structure resembles more that of the BaAl2O4 than the CaAl4O7 phase. The TEM results suggest that the crystallite sizes are in the nanometer scale with rod-like particles. PL results showed multiple emission peaks located at 436, 590, 616, 656, and 703 nm, which were assigned to the intrinsic defects within the BC matrix, 5D0 ⟶ 7F1, 5D0 ⟶ 7F2, 5D0 ⟶ 7F3, and 5D0 ⟶ 7F4 transitions of Eu3+, respectively. The decay curves evidently showed that the nanophosphors have persistent luminescence. The Commission Internationale de l’Eclairage (CIE) analysis revealed that doping has tuned the emission colour from blue to orange-red. The results indicate that the Eu3+-doped samples can potentially be used in the orange/red-emitting phosphors.

Preparation and Characterization of Zn-Containing Hydroxyapatite/TiO2 Composite Coatings on Ti Alloys

2011 ◽  
Vol 685 ◽  
pp. 367-370 ◽  
Author(s):  
Min Qi ◽  
Da Yi Yang ◽  
Jing Ying Zhang ◽  
Hong Jun Ai
Keyword(s):  
Adhesion Strength ◽  
Composite Coatings ◽  
Energy Dispersive Spectrometer ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Zn Content ◽  
Micro Arc Oxidation ◽  
Gel Technique ◽  
Bacteria Resistance

In order to improve the osteoblast growth and bacteria resistance, Zn-containing hydroxyapatite (Zn-HA) and titanium oxide (TiO2) composite coatings were prepared to improve binding between coating and Ti substrate. TiO2 film was prepared on the surface of Ti by micro-arc oxidation (MAO) and Zn-HA coating was deposited on TiO2 using sol–gel technique. Phase structure, composition and microstructure of the surface coatings were analyzed by X-ray diffraction (XRD) and Energy Dispersive Spectrometer (EDS), respectively. The adhesion strength between the coatings with different Zn content was measured by tensile testing. The results showed that there was no significant influence of Zn content on adhesion strength between coating and Ti substrate.

Characterization of SrBi2Nb2O9 Thin Films Prepared by Sol Gel Technique

1996 ◽  
Vol 459 ◽  
Author(s):  
E. Ching-Prado ◽  
W. Pérez ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
D. Ravichandran ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Band ◽  
Sol Gel ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Ft Ir ◽  
Gel Technique ◽  
High Degree ◽  
First Time

ABSTRACTThin films of SrBi2Nb2O9 (SBN) with thicknesses of 0.1, 0.2, and 0.4 μ were grown by Sol-gel technique on silicon, and annealed at 650°C. The SBN films were investigated by Raman scatering for the first time. Raman spectra in some of the samples present bands around 60, 167, 196, 222, 302, 451, 560, 771, 837, and 863 cm−1, which correspond to the SBN formation. The study indicates that the films are inhomogeneous, and only in samples with thicknesses 0.4 μ the SBN material was found in some places. The prominent Raman band around 870 cm−1, which is the A1g mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift in different places in the same sample, as well as from sample to sample. The frequency shifts and the width of the Raman bands are discussed in term of ions in non-equilibrium positions. FT-IR spectra reveal a sharp peak at 1260 cm−1, and two broad bands around 995 and 772 cm−1. The bandwidths of the latter two bands are believed to be associated with the presence of a high degree of defects in the films. The experimental results of the SBN films are compared with those obtained in SBT (T=Ta) films. X-ray diffraction and SEM techniques are also used for the structural characterization.

scholarly journals Dielectric properties and leakage current of MgO/(Ba0.8Sr0.2)TiO3 heterostructured films prepared by sol-gel technique

2006 ◽  
Vol 55 (4) ◽  
pp. 2069
Author(s):  
Jia Jian-Feng ◽  
Huang Kai ◽  
Pan Qing-Tao ◽  
Li Shi-Guo ◽  
He De-Yan
Keyword(s):  
Dielectric Properties ◽  
Leakage Current ◽  
Sol Gel ◽  
Gel Technique

scholarly journals Calcination Effect on Structural Trasformation of Barium Titanite Ferroelectric Ceramic by Sol-Gel Method

2019 ◽  
Vol 9 (1) ◽  
pp. 5893-5896
Keyword(s):  
Glacial Acetic Acid ◽  
Sol Gel ◽  
Ferroelectric Ceramic ◽  
Tetrabutyl Titanate ◽  
Chemical Modifier ◽  
Barium Acetate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gel Technique ◽  
Scanning Electron

High purity barium titanate BaTiO3 was successfully synthesized by using the sol-gel technique. Barium acetate Ba(CH3COO)2 and tetrabutyl titanate, Ti(C4H9O)4 was dissolved moderately in the solvent of glacial acetic acid and ethanol was added as the chemical modifier. The synthesized BaTiO3 nanoparticle was calcined at the temperature range of 700 ºC to 1100 ºC. The powders were further characterized by X-ray diffraction and scanning electron microscopy (SEM). Fined BaTiO3 powders result indicates the phase of tetragonal structures and high crystallites of BaTiO3. It was observed that the crystallinity and particle size of BaTiO3 is greatly influenced by the calcination temperature.

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