Dielectric Properties of Y3Fe5O12 (YIG) Prepared at Different Molarities of NaOH

2020 ◽  
Vol 13 (3) ◽  
pp. 221-226
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Yttrium Iron Garnet ◽  
Lattice Parameter ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Yttrium Iron ◽  
X Ray ◽  
Co Precipitation ◽  
Iron Garnet

Abstract: In this study, Yttrium Iron Garnet (Y3Fe5O12) (YIG) powders were synthesized via co-precipitation method, followed by calcining the precipitates at 1100˚C. The garnets produced were obtained from aqueous iron and yttrium chloride mixtures using different molarities of NaOH (M=2, 3, 4 and 5) at pH=12. The phase formation and crystallography were investigated using X-ray diffraction (XRD), the morphology was investigated using transmission electron microscopy (TEM) and the dielectric properties were measured using an impedance analyzer in the frequency range 0.5 - 5MHz, in a temperature range 22 - 350˚C. X-ray diffraction peaks showed the formation of cubic YIG with lattice parameter varying between 12.334 and 12.339 Å. The grain size, measured from TEM images, decreased with the increase of the molarity of NaOH. Plots of the real part of the dielectric constant ε′, the imaginary part of the dielectric constant ε'', loss tangent tan δ and ac conductivity σac as functions of frequency and temperature, respectively, were obtained. It was observed that the highest values of the dielectric constant were obtained in the 2M sample. Keywords: Dielectric properties, Yttrium Iron Garnet (YIG), Co-precipitation method, NaOH molarity.

The Mixed Magnetic Property of Co0.76Cu0.74[Fe(CN)6]·7.5H2O

2018 ◽  
Vol 71 (11) ◽  
pp. 914
Author(s):  
Yanfang Xia ◽  
Min Liu ◽  
Duxin Li
Keyword(s):  
Magnetic Field ◽  
Magnetic Moment ◽  
Effective Magnetic Moment ◽  
Lattice Parameter ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Co Precipitation ◽  
The Magnetic Field

Co0.76Cu0.74[Fe(CN)6]·7.5H2O was prepared as a powder by a chemical co-precipitation method. The powder X-ray diffraction patterns were indexed to the typical face-centred cubic structure with the lattice parameter a 10.55(2) Å. The temperature dependence of the χ−1 curve obeys the Curie–Weiss law (χ = C/(T – θ)) in the temperature range of 180–300 K. According to Curie–Weiss law, the calculated θ value is −54.82 K. In the paramagnetic state at 300 K, the effective magnetic moment (μeff = (8χT)1/2) is 3.58 μB per formula unit. The calculated theoretical effective magnetic moment is 4.06 μB. The magnetic field cooling measurements under a 200 Oe applied magnetic field show that the saturation magnetization value at 2 K of the complex Co0.76Cu0.74[Fe(CN)6]·7.5H2O is 1.528 emu g−1.

Sol-Gel Derived Ferrites: Synthesis and Characterization

2011 ◽  
Vol 222 ◽  
pp. 235-238 ◽  
Author(s):  
Aurelija Gatelyte ◽  
Darius Jasaitis ◽  
Aldona Beganskiene ◽  
Aivaras Kareiva
Keyword(s):  
Transition Metal ◽  
Yttrium Iron Garnet ◽  
Sol Gel ◽  
Synthesis And Characterization ◽  
Ceramic Pigments ◽  
X Ray Diffraction ◽  
Yttrium Iron ◽  
X Ray ◽  
Cobalt Nickel ◽  
Iron Garnet

In the present work, the sinterability and formation of nanosized yttrium iron garnet (Y3Fe5O12), yttrium perovskite ferrite (YFeO3), cobalt, nickel and zinc iron spinel (CoFe2O4, NiFe2O4 and ZnFe2O4, respectively) powders by an aqueous sol-gel processes are investigated. The phase purity of synthesized nano-compounds was characterized by powder X-ray diffraction analysis (XRD). The microstructural evolution and morphological features of obtained transition metal ferrites were studied by scanning electron microscopy (SEM). The possible application of these nanosized transition metal ferrites as ceramic pigments was demonstrated.

scholarly journals X-RD, TEM, Magnetic Studies on NixZn1-xFe2O4 (Where x= 0.2, 0.4, 0.5, 0.6 and 0.8) Nano Scale Particles by Chemical Co-Precipitation Method

2015 ◽  
Vol 60 ◽  
pp. 20-24
Author(s):  
B. Suryanarayana ◽  
V. Raghavendra ◽  
K. Chandra Mouli
Keyword(s):  
Average Particle Size ◽  
Lattice Parameter ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Zinc Nanoparticles ◽  
X Ray ◽  
Xrd Patterns ◽  
Co Precipitation

Nickel zinc nanoparticles NixZn1-xFe2O4 (where x= 0.2, 0.4, 0.5, 0.6 and 0.8) by Chemical Co-Precipitation method. The samples were characterised by X-ray diffraction (XRD), TEM, VSM .The powders of XRD patterns confirm a single spinel crystalline phase with cubic structure formation with no indication of any other secondary or unidentified phase. The lattice parameter changed from 8.336 Å to 8.382 Å. The average particle size ranged 20 to 80 nm was observed by TEM.

scholarly journals Pembuatan Ba0,8Sr0,2TiO3 menggunakan Metode Co-precipitation dengan Variasi Suhu Sintering

2017 ◽  
Vol 7 (1) ◽  
pp. 51
Author(s):  
Isma Alvia Nita ◽  
Yofentina Iriani ◽  
Fahru Nurosyid
Keyword(s):  
Dielectric Constant ◽  
Crystal Size ◽  
Sintering Temperature ◽  
Microstructure Characterization ◽  
Temperature Measurements ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lcr Meter ◽  
Co Precipitation

<p>Ba<sub>0,8</sub>Sr<sub>0,2</sub>TiO<sub>3 </sub>was made by co-precipitation method with the sintering temperature of 600<sup>o</sup>C, 700<sup>o</sup>C, 800<sup>o</sup>C and 900<sup>o</sup>C for 4 hours. Sintering temperature was varied to investigate its effect on microstructure and dielectric constant of Ba<sub>0,8</sub>Sr<sub>0,2</sub>TiO<sub>3</sub>. microstructure characterization was performed by X-Ray Diffraction (XRD) instrument. Dielectric constant characterization was perform by LCR meter. The crystal size increased significantly with increasing sintering temperature. Measurements of dielectric constant were performed at range of frequency 0.01 to 100 KHz. Dielectric constant value is highest at the lowest frequency. Dielectric constant value size increased significantly with increasing sintering temperature.</p>

Effect of Surfactants on Structural and Dielectric Properties of Cobalt Ferrite

2014 ◽  
Vol 938 ◽  
pp. 14-18 ◽  
Author(s):  
Hemal Khatri ◽  
G. Packiaraj ◽  
Rajshree B. Jotania
Keyword(s):  
Dielectric Properties ◽  
Cobalt Ferrite ◽  
Low Frequency ◽  
Precipitation Method ◽  
Ammonium Bromide ◽  
X Ray Diffraction ◽  
X Ray ◽  
Low Field ◽  
Co Precipitation ◽  
Triton X

Cobalt ferrite (Cofe2o4) particles were synthesized with and without presence of surfactants using a co-precipitation method. Three surfactants Cetyl Tri methyl Ammonium Bromide (CTAB-cationic), Sodium dodecylbenzenesulphonate (anionic), Triton X-100 (nonionic), were used and investigate their effects on the structural and dielectric properties of CoFe2O4 particles. The ferrite precursors were first pre calcined in a muffle furnace at 500°C and then calcined at 950°C. Structural, dielectric and magnetic properties of prepared particles were investigated using X-ray powder diffraction, Dielectric and Low field ac magnetic susceptibility measurement. Phase purity of prepared samples was confirmed by X-ray diffraction. The sample with surfactant Triton X-100 shows the highest values of dielectric constant at low frequency.

Analysis and lattice imaging of a transitional event on garnets

1978 ◽  
Vol 36 (1) ◽  
pp. 270-271
Author(s):  
J.Y. Laval
Keyword(s):  
Yttrium Iron Garnet ◽  
Reciprocal Lattice ◽  
Transitional Zone ◽  
Lattice Imaging ◽  
Yttrium Iron ◽  
X Ray ◽  
Ionic Process ◽  
The Matrix ◽  
High Resolution Technique ◽  
Iron Garnet

The exsolution of magnetite from a substituted Yttrium Iron Garnet, containing an iron excess may lead to a transitional event. This event is characterized hy the formation of a transitional zone at the center of which the magnetite nucleates (Fig.1). Since there is a contrast between the matrix and these zones and since selected area diffraction does not show any difference between those zones and the matrix in the reciprocal lattice, it is of interest to analyze the structure of the transitional zones.By using simultaneously different techniques in electron microscopy, (oscillating crystal method microdiffraction and X-ray microanalysis)one may resolve the ionic process corresponding to the transitional event and image this event subsequently by high resolution technique.

scholarly journals Photoluminescent Properties of Hydroxyapatite and Hydroxyapatite/Multi-Walled Carbon Nanotube Composites

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 832
Author(s):  
Edna X. Figueroa-Rosales ◽  
Javier Martínez-Juárez ◽  
Esmeralda García-Díaz ◽  
Daniel Hernández-Cruz ◽  
Sergio A. Sabinas-Hernández ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Hexagonal Phase ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Multi Walled Carbon Nanotube ◽  
Nanotube Composites ◽  
Carbon Nanotube Composites ◽  
Co Precipitation ◽  
Functionalized Mwcnts

Hydroxyapatite (HAp) and hydroxyapatite/multi-walled carbon nanotube (MWCNT) composites were obtained by the co-precipitation method, followed by ultrasound-assisted and microwave radiation and thermal treatment at 250 °C. X-ray diffraction (XRD) confirmed the presence of a hexagonal phase in all the samples, while Fourier-transform infrared (FTIR) spectroscopy elucidated the interaction between HAp and MWCNTs. The photoluminescent technique revealed that HAp and the composite with non-functionalized MWCNTs present a blue luminescence, while the composite with functionalized MWCNTs, under UV-vis radiation shows an intense white emission. These findings allowed presentation of a proposal for the use of HAp and HAp with functionalized MWCNTs as potential materials for optoelectronic and medical applications.

Photocatalytic Activity of Fe-Doped ZnO/Montmorillonite Nanocomposite for Degradation of Malachite Green

2015 ◽  
Vol 827 ◽  
pp. 19-24 ◽  
Author(s):  
Nur Afifah ◽  
Nadia Febiana Djaja ◽  
Rosari Saleh
Keyword(s):  
Photocatalytic Activity ◽  
Malachite Green ◽  
Organic Dyes ◽  
Uv Light ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spin Resonance ◽  
Doped Zno ◽  
Co Precipitation

In this study, the photocatalytic activity of pure Fe- doped ZnO and Fe- doped ZnO/Montmorillonite nanocomposite has been investigated for the degradation of malachite green under UV light irradiation. Both photocatalysts were synthesized using co-precipitation method and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier-transform infrared absorption, and electron spin resonance. The results showed that the photocatalytic efficiency is better in the presence of montmorillonite compared to pure Fe- doped ZnO. To detect the possible reactive species involved in degradation of organic dyes control experiments with introducing scavengers into the solution of organic dyes were carried out. It is found that electron plays an important role in the degradation of malachite green.

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