Annealing Effects on the Physical and Magnetic Properties of Tb1.5Y1.5Fe5O12 Films Nanoparticles Prepared by Sol-Gel Method

2013 ◽  
Vol 756 ◽  
pp. 91-98 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah

Terbium –substituted yttrium iron garnet (Tb1.5Y1.5Fe5O12) films nanoparticles were successfully prepared by a sol-gel method. The films were deposited on the quartz substrate using spin coating technique. To study effect of annealing temperature, the annealing process was executed at 700, 800 and 900 °C in air for 2 hours. The X-ray diffraction (XRD) proved that the pure phase of garnet structure was detected for the film annealed at 900 °C. The lattice parameter increased with the increment of annealing temperature and the highest value of 12.35 Å was obtained at 900 °C. Field Emission Scanning Electron Microscope (FE-SEM) results showed that the particle size increased from 43nm to 56nm as annealing temperature increased from 700 to 900°C. The film’s thickness also affected by increasing of annealing temperature and become thin at 900 °C due to densification process occurred at high annealing temperature. The elemental compositions of the Tb1.5Y1.5Fe5O12 film were detected using an Energy Dispersive X-raySpectroscopy (EDX). Magnetic properties at room temperature were measured using a Vibrating Sample Magnetometer (VSM).The saturation magnetization Ms increased with the annealingtemperature and showed a high value of 104emu/cm3, but the coercivity Hc of the film was decreased due to the increment of the particle size. Normal 0 21 false false false MS X-NONE X-NONE MicrosoftInternetExplorer4 Terbium –substituted yttrium iron garnet (Tb1.5Y1.5Fe5O12) films nanoparticles were successfully prepared by a sol-gel method. The films were deposited on the quartz substrate using spin coating technique. To study effect of annealing temperature, the annealing process was executed at 700, 800 and 900°C in air for 2 hours. The X-ray diffraction (XRD) proved that the pure phase of garnet structure was detected for the film annealed at 900 °C. The lattice parameter increased with the increment of annealing temperature and the highest value of 12.35 Å was obtained at 900 °C. Field Emission Scanning Electron Microscope (FE-SEM) results showed that the particle size increased from 43nm to 56nm as annealing temperature increased from 700 to 900 °C. The film’s thickness also affected by increasing of annealing temperature and become thin at 900 °C due to densification process occurred at high annealing temperature. The elemental compositions of the Tb1.5Y1.5Fe5O12 film were detected using an Energy Dispersive X-ray Spectroscopy (EDX). Magnetic properties at room temperature were measured using a Vibrating Sample Magnetometer (VSM).The saturation magnetization Ms increased with the annealing temperature and showed a high value of 104emu/cm3, but the coercivity Hc of the film was decreased due to the increment of the particle size. st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

2016 ◽  
Vol 34 (2) ◽  
pp. 362-367 ◽  
Author(s):  
I. Yarici ◽  
M. Erol ◽  
E. Celik ◽  
Y. Ozturk

AbstractCerium substituted yttrium iron garnet (Ce0.2Y2.8Fe5O12; Ce-YIG) nanoparticles were produced via the sol-gel method from solutions of Ce-, Y- and Fe-based precursors, a solvent and a chelating agent. The solutions were dried at 200°C and heat treated at temperatures between 800 °C and 1400°C for 3 h in air. The effects of pH and annealing temperature on the structure, phase formation, magnetic properties and crystallite size were investigated. A cubic YIG phase was obtained for the sample annealed at 1400 °C. The presented results showed that the pH value of the starting solution affects the crystal size and consequently, the saturation magnetization.


2011 ◽  
Vol 268-270 ◽  
pp. 356-359 ◽  
Author(s):  
Wen Song Lin ◽  
C. H. Wen ◽  
Liang He

Mn, Fe doped ZnO powders (Zn0.95-xMnxFe0.05O2, x≤0.05) were synthesized by an ameliorated sol-gel method, using Zn(CH3COO)2, Mn(CH3COO)2and FeCl2as the raw materials, with the addition of vitamin C as a kind of chemical reducer. The resulting powder was subsequently compacted under pressure of 10 MPa at the temperature of 873K in vacuum. The crystal structure and magnetic properties of Zn0.95-xMnxFe0.05O2powder and bulk samples have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of manganese, iron and zinc in the samples. The x-ray diffraction (XRD) results showed that Zn0.95-xMnxFe0.05O (x≤0.05) samples were single phase with the ZnO-like wurtzite structure. No secondary phase was found in the XRD spectrum. X-ray photoelectron spectroscopy (XPS) showed that Fe and Mn existed in Zn0.95-xMnxFe0.05O2samples in Fe2+and Mn2+states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Mn, Fe co-doped ZnO samples.


2019 ◽  
Vol 236 ◽  
pp. 547-549 ◽  
Author(s):  
L.R.F. Leal ◽  
Y. Guerra ◽  
E. Padrón-Hernández ◽  
A.R. Rodrigues ◽  
F.E.P. Santos ◽  
...  

Author(s):  
T. Pikula ◽  
T. Szumiata ◽  
K. Siedliska ◽  
V. I. Mitsiuk ◽  
R. Panek ◽  
...  

AbstractIn this work, BiFeO3 powders were synthesized by a sol–gel method. The influence of annealing temperature on the structure and magnetic properties of the samples has been discussed. X-ray diffraction studies showed that the purest phase was formed in the temperature range of 400 °C to 550 °C and the samples annealed at a temperature below 550 °C were of nanocrystalline character. Mössbauer spectroscopy and magnetization measurements were used as complementary methods to investigate the magnetic state of the samples. In particular, the appearance of weak ferromagnetic properties, significant growth of magnetization, and spin-glass-like behavior were observed along with the drop of average grain size. Mössbauer spectra were fitted by the model assuming cycloidal modulation of spins arrangement and properties of the spin cycloid were determined and analyzed. Most importantly, it was proved that the spin cycloid does not disappear even in the case of the samples with a particle size well below the cycloid modulation period λ = 62 nm. Furthermore, the cycloid becomes more anharmonic as the grain size decreases. The possible origination of weak ferromagnetism of the nanocrystalline samples has also been discussed.


2016 ◽  
Vol 846 ◽  
pp. 626-634 ◽  
Author(s):  
Noor Baayah Ibrahim ◽  
Ftema W. Aldbea ◽  
Akmal Zaini Arsad ◽  
Noorhasniyah Md Rodee

Yttrium iron garnet (Y3Fe5O12) films were prepared by a sol-gel method followed by an annealing process at 500,600,700,800, and 900°C in oxygen atmosphere for 2 hours. The microstructure characterization carried out by an X-ray diffractometer showed that the film started to crystalline into YIG phase at 700°C. The average grain size of the films measured using a field emission scanning electron microscope gave the average value of 20 to 70 nm. The magnetic properties measured by a vibrating sample magnetometer showed that all of the films were soft magnetic materials. The saturation magnetization values increased with the increment of annealing temperature. However, the coercivity values were independence with temperatures.Keywords:Thinfilms;Crystalline;Sol-gelmethod;


2019 ◽  
Vol 966 ◽  
pp. 363-369
Author(s):  
Utami Widyaiswari ◽  
Budhy Kurniawan ◽  
Agung Imaduddin ◽  
Isao Watanabe

Mixed valence manganite materials have been studied due to their interesting physical properties such as their magnetoresistance (MR) effect. The change of Mn3+/Mn4+ ratio affects the possible bonds between anion and cation and their spin structure that may occur in the samples. The aim of this research is to study the change of magnetoresistance effect and magnetic properties of La0.67Sr0.33MnO3 (LSMO) by doping the Mn site with Ni ion. La0.67Sr0.33Mn1-xNixO3 samples were synthesized by using sol-gel method and characterized by using X-ray diffractometer (XRD) and Energy Dispersive X-ray spectroscopy (EDX) to confirm whether Ni has been doped successfully to the parental compound or not. XRD results showed that the samples have a single phase and Ni peak has been detected in the EDX result of Ni-doped LSMO. Resistivity and magnetic measurement showed that LSMO material has ferromagnetic metallic behavior, while x = 0.20 Ni-doped LSMO sample showed paramagnetic insulator behavior. The absolute value of the MR for un-doped sample is higher than the doped sample when the low field is applied, while under the influence of the high magnetic field, it become smaller than the doped sample.


2012 ◽  
Vol 535-537 ◽  
pp. 787-790
Author(s):  
Shu Lan Guo ◽  
Min Wang ◽  
Su Hua Lv ◽  
Jia Li ◽  
Xian Chang Du

The properties of YSZ-Ni-Cr cermet fabricated by Sol-Gel Method(YSZ-Ni-Cr powder was synthesized by coprecipitation method at 850°C for 2 h and was processed into YSZ-Ni-Cr cermet by hot-press sintering at 1350°C for 1 h)was explored. The identification of phases was carried out using a X-ray diffractometer (XRD). The particle size and morphology was determined by electron microscopys(SEM/TEM) The conductivity had a tendency to decrease with increasing temperature. This behavior can be accounted for that there are two conduction paths through the cermet, an electronic path through the (Ni,Cr) metal phase and an ionic path through the ZrO2-Y2O3 phase.


Sign in / Sign up

Export Citation Format

Share Document