Effect of Heat Treatment on Structural, Magnetic and Electric Properties of Z-Type Barium Cobalt Hexaferrite Powder

2014 ◽  
Vol 938 ◽  
pp. 24-29 ◽  
Author(s):  
Neha Solanki ◽  
G. Packiaraj ◽  
Rajshree B. Jotania
Keyword(s):  
Heat Treatment ◽  
Ac Conductivity ◽  
Room Temperature ◽  
Sintering Temperature ◽  
Sol Gel ◽  
Frequency Range ◽  
Treatment Conditions ◽  
Auto Combustion ◽  
Powder Samples ◽  
Combustion Technique

Z-type hexaferrite with composition Ba3Co2Fe24O41has been synthesized using a sol-gel auto combustion technique. The obtain combusted powder was sintered at 500 OC and followed by 950 OC for 4 hrs in a muffle furnace. The effect of different sintering temperature on crystal structure, crystallite size, microstructure and dielectric properties were systematically investigated. The prepared barium cobalt hexaferrite powder samples were characterized using different experimental techniques like FTIR, XRD, AC conductivity and specific magnetization measurements. It was observed from XRD results that heat treatment conditions play significant role in the formation of hexaferrite phase. AC conductivity measurements were carried out at room temperature in frequency range of 20Hz to 2MHz. All the samples show the frequency dependent phenomena, i.e. the AC conductivity increases with increasing frequency.

scholarly journals Structures and properties of Mg0.95Mn0.01TM0.04O (TM = Co, Ni, and Cu) nanoparticles synthesized by sol–gel auto combustion technique

RSC Advances ◽  
2018 ◽  
Vol 8 (25) ◽  
pp. 14120-14128 ◽  
Author(s):  
M. A. Dar ◽  
Dinesh Varshney
Keyword(s):  
Dielectric Properties ◽  
Room Temperature ◽  
Sol Gel ◽  
Cu Nanoparticles ◽  
Structures And Properties ◽  
Auto Combustion ◽  
Combustion Technique

The room temperature structural, optical and dielectric properties of Mg0.95Mn0.05O and Mg0.95Mn0.01TM0.04O (TM = Co, Ni, and Cu) nanoparticles are reported.

Structural and Dielectric Studies of Cu Substituted Barium Hexaferrite Prepared by Sol-Gel Auto Combustion Technique

2013 ◽  
Vol 209 ◽  
pp. 102-106 ◽  
Author(s):  
Ganapathi Packiaraj ◽  
Nital R. Panchal ◽  
Rajshree B. Jotania
Keyword(s):  
Room Temperature ◽  
Single Phase ◽  
Initial Level ◽  
Sol Gel ◽  
Barium Hexaferrite ◽  
Combustion Method ◽  
Auto Combustion ◽  
Combustion Technique ◽  
Substituted Barium Hexaferrite ◽  
Copper Substitution

In the present study, a series of Cu substituted M type Barium hexagonal ferrite BaCuxFe12-xO19 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) has been synthesized using a Sol- gel auto combustion method. The aim of the present work was to investigate the effects of Cu/Fe ratio on the crystallography and dielectric properties. The XRD studies reveal a formation of the single phase BaFe12O19 at the initial level and mixed phase of S, M and Y hexaferrite at the higher level of copper substitution. The dielectric measurements were carried out at room temperature in a frequency range of 20 Hz to 2MHz. the dielectric constant is found to decrease with the increase of frequency for all the compositions.

Structural, Morphological and Magnetic Characterization of Sm-substituted Ni-Zn Ferrite

2020 ◽  
Vol 10 (2) ◽  
pp. 152-156 ◽  
Author(s):  
Muhammad Hanif bin Zahari ◽  
Beh Hoe Guan ◽  
Lee Kean Chuan ◽  
Afiq Azri bin Zainudin
Keyword(s):  
Magnetic Properties ◽  
Rare Earth ◽  
Saturation Magnetization ◽  
Sol Gel ◽  
Magnetic Behavior ◽  
Rare Earth Ions ◽  
Ion Concentration ◽  
Zn Ferrite ◽  
Auto Combustion ◽  
Combustion Technique

Background: Rare earth materials are known for its salient electrical insulation properties with high values of electrical resistivity. It is expected that the substitution of rare earth ions into spinel ferrites could significantly alter its magnetic properties. In this work, the effect of the addition of Samarium ions on the structural, morphological and magnetic properties of Ni0.5Zn0.5SmxFe2-xO4 (x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) synthesized using sol-gel auto combustion technique was investigated. Methods: A series of Samarium-substituted Ni-Zn ferrite nanoparticles (Ni0.5Zn0.5SmxFe2-xO4 where x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10) were synthesized by sol-gel auto-combustion technique. Structural, morphological and magnetic properties of the samples were examined through X-Ray Diffraction (XRD), Field-Emission Scanning Electron Microscope (FESEM) and Vibrating Sample Magnetometer (VSM) measurements. Results: XRD patterns revealed single-phased samples with spinel cubic structure up to x= 0.04. The average crystallite size of the samples varied in the range of 41.8 – 85.6 nm. The prepared samples exhibited agglomerated particles with larger grain size observed in Sm-substituted Ni-Zn ferrite as compared to the unsubstituted sample. The prepared samples exhibited typical soft magnetic behavior as evidenced by the small coercivity field. The magnetic saturation, Ms values decreased as the Sm3+ concentration increases. Conclusion: The substituted Ni-Zn ferrites form agglomerated particles inching towards more uniform microstructure with each increase in Sm3+ substitution. The saturation magnetization of substituted samples decreases with the increase of samarium ion concentration. The decrease in saturation magnetization can be explained based on weak super exchange interaction between A and B sites. The difference in magnetic properties between the samples despite the slight difference in Sm3+ concentrations suggests that the properties of the NiZnFe2O4 can be ‘tuned’, depending on the present need, through the substitution of Fe3+ with rare earth ions.

LiNiO2 Thin Films Fabricated by Diffusion of Li on Ni Tapes

2007 ◽  
Vol 336-338 ◽  
pp. 505-508
Author(s):  
Cheol Jin Kim ◽  
In Sup Ahn ◽  
Kwon Koo Cho ◽  
Sung Gap Lee ◽  
Jun Ki Chung
Keyword(s):  
Thin Films ◽  
Heat Treatment ◽  
Grain Size ◽  
Sol Gel ◽  
Surface Oxidation ◽  
Cold Isostatic Pressing ◽  
Tube Furnace ◽  
Treatment Conditions ◽  
Average Grain Size ◽  
Cold Rolling And Annealing

LiNiO2 thin films for the application of cathode of the rechargeable battery were fabricated by Li ion diffusion on the surface oxidized NiO layer. Bi-axially textured Ni-tapes with 50 ~ 80 μm thickness were fabricated using cold rolling and annealing of Ni-rod prepared by cold isostatic pressing of Ni powder. Surface oxidation of Ni-tapes were conducted using tube furnace or line-focused infrared heater at 700 °C for 150 sec in flowing oxygen atmosphere, resulted in NiO layer with thickness of 400 and 800 μm, respectively. After Li was deposited on the NiO layer by thermal evaporation, LiNiO2 was formed by Li diffusion through the NiO layer during subsequent heat treatment using IR heater with various heat treatment conditions. IR-heating resulted in the smoother surface and finer grain size of NiO and LiNiO2 layer compared to the tube-furnace heating. The average grain size of LiNiO2 layer was 0.5~1 μm, which is much smaller than that of sol-gel processed LiNiO2. The reacted LiNiO2 region showed homogeneous composition throughout the thickness and did not show any noticeable defects frequently found in the solid state reacted LiNiO2, but crack and delamination between the reacted LiNiO2 and Ni occurred as the reaction time increased above 4hrs.

Structural, Magnetic and Dielectric Analysis of Higher Magnetic Mn Doped Zn-Cr Oxide Nanoparticles

2021 ◽  
Vol 9 (VI) ◽  
pp. 95-102
Author(s):  
S. D. Balsure
Keyword(s):  
Type Strain ◽  
Sol Gel ◽  
Hexagonal Wurtzite Structure ◽  
Xrd Analysis ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Microstructural Parameters ◽  
Auto Combustion ◽  
Mn Doped ◽  
Combustion Technique

Higher magnetic Mn doped Zn-Cr oxide nanoparticles with general compositional formula MxZn0.95-xCr0.05O have been synthesized by using sol-gel auto combustion technique. Room temperature X-ray diffraction (XRD) technique has been employed to study the structural and microstructural parameters of the as-prepared samples. XRD analysis confirms the phase purity and hexagonal wurtzite structure of all the samples. Replacement of Zn2+ ions by Mn2+ ions shifts peak positions slightly towards the lower angles which in turn expands the lattice lengths ‘a’ from 3.2487 to 3.2528 Å and ‘c’ from 5.2043 to 5.2118 Å. Crystallite size obtained from Scherrer equation was confirmed by Williamson – Hall (W-H) and size – strain plot methods (SSP). Both W-H and SSP methods reveals the tensile type strain for undoped sample and comprehensive type strain for Mn2+ doped samples. Magnetic properties were investigated by using vibrating sample magnetometer. Diluted ferromagnetic behaviour is observed for all the samples and saturation magnetization (MS) increases from 0.0514 to 0.1163 emu/gm. Two-probe technique was employed to understand the dielectric behaviour of the samples as a function of frequency. At lower frequency region, both dielectric constant () and dielectric loss tangent (tan ) shows higher values and decreases with the increasing applied frequency.

Characteristics of Lithium Polysilicate Electrolyte Synthesized by Sol-Gel Processing

2007 ◽  
Vol 124-126 ◽  
pp. 1031-1034
Author(s):  
Bong Soo Jin ◽  
Bok Ki Min ◽  
Chil Hoon Doh
Keyword(s):  
Heat Treatment ◽  
Acid Treatment ◽  
Treatment Time ◽  
Sol Gel ◽  
Silicate Solution ◽  
Treatment Temperature ◽  
Lithium Silicate ◽  
Treatment Conditions ◽  
Xrd Patterns ◽  
Si Wafer

To find out suitable Si surface treatment and heat treatment conditions, acid treatment of Si wafer was done for lithium polysilicate electrolyte coating on Si wafer. In case of HCl treatment, the wet angle of a sample is 30o, which is the smallest wet angle of other acid in this experiment. Acid treatment time is 10 min, which is no more change of wet angle. Lithium polysilicate electrolyte was synthesized by hydrolysis and condensation of lithium silicate solution using perchloric acid. Thermal analysis of lithium polysilicate electrolyte shows the weight loss of ~23 % between 400 and 500 , which is due to the decomposition of LiClO4. The XRD patterns of the obtained lithium polysilicate electrolyte also show the decrement of LiClO4 peak at 400 . The optimum heat treatment temperature is below 400 , which is the suitable answer for lithium polysilicate electrolyte.

scholarly journals Investigation of Structural and Magnetic Properties of Multiferroic La1-Xyxfeo3perovskites, Prepared by Citrate Auto-Combustion Technique

2019 ◽  
Vol 15 ◽  
pp. 6056-6077
Author(s):  
Ahmed Hassan Ibrahim ◽  
Yehia Mohammed Abbas ◽  
Shehab Esmail Mohammed ◽  
Ahmed Bakry Mansour
Keyword(s):  
Magnetic Properties ◽  
Sol Gel ◽  
Particle Diameter ◽  
Average Particle ◽  
Microscopy Imaging ◽  
Transmission Microscopy ◽  
Auto Combustion ◽  
Structural And Magnetic Properties ◽  
Combustion Technique ◽  
Synchrotron Xrd

In this work, we studied the structural and magnetic properties of multiferroic La1-xYxFeO3 perovskites, (x= 0.0, 0.05, 0.1, 0.15, 0.25 and 0.3) which synthesized through Sol-gel auto-combustion technique using a citric acid as a fuel. The room temperature synchrotron X-ray diffraction (XRD) analysis revealed that the all the synthesized samples consisted of the polycrystalline orthorhombic structure perovskites(space group pnma), and tolerance factor confirmed the phase stability of the prepared perovskite system.The Williamson-Hall plot based on synchrotron XRD data were employed to estimate the average particle diameter and varies from 18 nmto 27.8 nm.For a deeper insight of the crystal structure, high resolution transmission microscopy imaging (HRTEM) was performed. The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident. Many of crystallographic parameters and electron density measurements were calculated by Rietveld refinement of synchrotron XRD data. La1-xYxFeO3 perovskite crystalsarecanted antiferromagnets with a weak ferromagnetism in room temperature.The magnetic properties were gotten through analyzing the magnetization versus temperature M(T) and M(H) hysteresis loop which characterized by a vibrating sample magnetometer (VSM). The molecular structure showed the decrease of the tilting of the octahedra <FeO6> with increasing Y content trying to strengthen the ferromagnetic character. Selected Area Electron Diffraction (SAED) patterns of the investigated samples exhibited spotty ring patterns,confirming the polycrystalline character.The orthoferrite La1-xYxFeO3 crystalsare a promising candidate for optical device applications in broad temperature range and high power system.

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