scholarly journals Structural, Dielectric, Magnetic and Optical Properties of Cerium Substituted Ni-Zn Mixed Ferrite

2017 ◽  
Vol 14 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Lovely George ◽  
C. Viji ◽  
Haisel Mathew ◽  
E.M. Mohammed
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Strain Effect ◽  
X Ray Diffraction ◽  
Semiconducting Materials ◽  
Octahedral Sites ◽  
In Doping ◽  
Wide Range ◽  
Diffraction Patterns ◽  
Lower Saturation

Ce3+ doped Nickel Zinc ferrites have been synthesised by sol-gel method followed by sintering at 4000C for 4 hours. Powder X-ray diffraction patterns of the prepared samples confirm the formation of single phase cubic spinel structure. Crystallite size of samples doped with Ce are smaller than that of undoped ferrite. The lattice parameters decrease with increase in doping concentration of Ce3+ ion. W-H plots are drawn to study the strain effect in crystal structure.SEM micrographs show formation of spherical shaped nanoparticles. The vibration bands corresponding to metal oxygen vibrations at tetrahedral and octahedral sites in the FTIR spectra are in the reported range suggesting Ce3+occupation on octahedral sites predominantly. The doped samples exhibited lower saturation magnetization. The relative permittivity is found to show a decreasing trend with increase in frequency for all the samples which is characteristic of normal ferrimagnetism. The AC conductivity initially increases with frequency then remains constant over a wide range of frequencies. The UV analyses give the band gap which is less than 2 eV for all the samples which show that these are semiconducting materials.

scholarly journals Magnetic properties of Cu and Al doped nano BaFe12O19 ceramics

2020 ◽  
Vol 10 (3) ◽  
pp. 5455-5459
Keyword(s):  
Saturation Magnetization ◽  
Single Phase ◽  
Sol Gel ◽  
Hexagonal Structure ◽  
Magnetic Characteristics ◽  
X Ray Diffraction ◽  
Cu Substitution ◽  
Auto Combustion ◽  
Diffraction Patterns ◽  
Combustion Technique

The BaCuxFe12-xO19 and BaAlxFe12-xO19 (x = 0.0, 0.4, 0.8, 1.2) materials were prepared via sol-gel auto combustion technique. Further, the X-ray diffraction patterns suggested the formation of single phase hexagonal structure. This work is aimed to study the effect of diamagnetic and paramagnetic elements on magnetic characteristics of BaFe12O19. The results established that in the case of diamagnetic (Cu) substitution, the saturation magnetization was increased and decreased alternatively. Furthermore, it was noticed that the coercivity values of all doped samples were lower than those of undoped samples. But the replacement of Fe3+ with paramagnetic (Al) element led to a decrease in saturation magnetization and to a significant increase in the coercive field.

Structural and Optical Properties of Ti1-x Fex O2 Nanoparticles

2013 ◽  
Vol 432 ◽  
pp. 16-19
Author(s):  
Lila A. Alkhtaby
Keyword(s):  
Raman Spectroscopy ◽  
Single Phase ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Anatase Structure ◽  
X Ray ◽  
Diffraction Patterns ◽  
Group D ◽  
Fe Ions

We have synthesized the Ti1-x Fex O2 (x=0.01, 0.02, 0.03 and 0.05) nanoparticles by the sol gel method to enhance the photocatalyic property of TiO2 .These samples are characterized using x-ray diffraction (XRD), Raman spectroscopy, Ultraviolet /Visible (UV/V) spectroscopy and fluorescence spectroscopy (PL). The x-ray diffraction patterns show that all the sample are formed in single phase with a complete solubility of Fe ions in the TiO2 matrix. TiO2 nanoparticles are tetragonal with anatase structure belong to the space group D41h 9 (141 ) /amd Raman active modes appear at 150, 196, 396, 483, 516 and 637cm-1. UV/V spectra show a decrease in the band gap with the increase in Fe concentration from 3.26 eV (1% Fe concentration) to3.11 eV (5% Fe concentration).

Synthesis and Characterization of Gadolinia-Doped Ceria with Manganese Addition

2012 ◽  
Vol 727-728 ◽  
pp. 1296-1301
Author(s):  
J.D. Yang ◽  
R.A. Rocha ◽  
R. Muccillo ◽  
E.N.S. Muccillo
Keyword(s):  
Single Phase ◽  
Powder Materials ◽  
Doped Ceria ◽  
X Ray Diffraction ◽  
Cation Complexation ◽  
Wide Range ◽  
Diffraction Patterns ◽  
Etched Surface

Ceria-based materials have been extensively studied due to their wide range of technological application. In this work, nanostructured powders of 20 mol% gadolinia-doped ceria pure and containing 1 mol% manganese were synthesized by the cation complexation technique. Powder materials were calcined at 600°C, uniaxially pressed and sintered in the 1200-1500°C range for soaking times of 1, 2 and 4 h. X-ray diffraction patterns evidenced a single-phase fluorite-like structure in all studied specimens. The evolution of grain sizes was evaluated by scanning electron microscopy on polished and thermally etched surface of sintered pellets. The relative density decreases for soaking times above 1300°C (with Mn) and 1400°C (without Mn). The grain size increases with manganese addition. The role of the additive on the electrical conductivity of gadolinia-doped ceria was evaluated by impedance spectroscopy measurements.

Impedance Spectroscopy Study of LiTaO3 Powder Synthesized via Sol-Gel Method

2012 ◽  
Vol 545 ◽  
pp. 275-278 ◽  
Author(s):  
Lili Widarti Zainuddin ◽  
Norlida Kamarulzaman
Keyword(s):  
Room Temperature ◽  
Single Phase ◽  
Sol Gel ◽  
Rhombohedral Structure ◽  
Spectroscopy Study ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Impedance Spectroscopy Study

A ceramics sample of LiTaO3 was prepared using a sol-gel method. The sample is annealed at 750 °C for 48 hours. X-ray diffraction analysis indicate the formation of single phase, rhombohedral structure. An ac impedance study was used to analyse the conductivity of LiTaO3 at room temperature and at various temperatures.

2D X-ray diffraction and molecular modelling of the crystalline structure of polyesters under uniaxial stress

2021 ◽  
pp. 096739112199822
Author(s):  
Ahmed I Abou-Kandil ◽  
Gerhard Goldbeck
Keyword(s):  
Crystalline Structure ◽  
Molecular Modelling ◽  
Three Dimensional ◽  
Uniaxial Stress ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Modelling Techniques ◽  
Diffraction Patterns

Studying the crystalline structure of uniaxially and biaxially drawn polyesters is of great importance due to their wide range of applications. In this study, we shed some light on the behaviour of PET and PEN under uniaxial stress using experimental and molecular modelling techniques. Comparing experiment with modelling provides insights into polymer crystallisation with extended chains. Experimental x-ray diffraction patterns are reproduced by means of models of chains sliding along the c-axis leading to some loss of three-dimensional order, i.e. moving away from the condition of perfect register of the fully extended chains in triclinic crystals of both PET and PEN. This will help us understand the mechanism of polymer crystallisation under uniaxial stress and the appearance of mesophases in some cases as discussed herein.

PREPARATION OF SOME NANO SIZE COLOSSAL MAGNETO RESISTANCE MATERIALS BY THE SOL-GEL ROUTE

2003 ◽  
Vol 17 (01) ◽  
pp. 19-24 ◽  
Author(s):  
K. PADMAVATHI ◽  
V. RAJAKUMARI ◽  
M. VITHAL ◽  
V. PRASD ◽  
S. V. SUBRAMANYAM ◽  
...  
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Resistivity Measurements ◽  
Temperature Range ◽  
Ionic Size ◽  
Colossal Magneto Resistance ◽  
Magneto Resistance ◽  
Nano Size

A series of colossal magneto resistance materials having compositional formula Re 0.67 Sr 0.33 MnO 3 (Re = Nd, Gd, … etc.) were prepared by the sol-gel method, using Ethylene glycol as a gelating reagent. The materials were characterized by the powder X-ray diffraction technique and are found to be single phase with orthorhombic structure. The particle size of all the materials were calculated using the well known Shearer formula and are found to be in the range of 20–45 nm. In order to determine the transition temperature (T c ), the DC electrical resistivity measurements were also carried out over a temperature range 80–300 K using the four probe method and it has been observed that the T c values are found to increase with increasing ionic size. Finally the magneto resistance measurements were also undertaken in the temperature range 80–300 K and it has been found that the MR values of these materials are better when compared with those prepared by the solid state reaction method.

Study on optical and magnetic properties of FexNi1-xMn2O4 materials

2021 ◽  
Vol 66 (1) ◽  
pp. 57-64
Author(s):  
Hang Pham Vu Bich ◽  
Yen Nguyen Hai ◽  
Mai Phung Thi Thanh ◽  
Dung Dang Duc ◽  
Hung Nguyen Manh ◽  
...  
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Vibrating Sample Magnetometer ◽  
Raman Scattering Spectrum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scattering Spectrum ◽  
Diffraction Diagram ◽  
Optical And Magnetic Properties ◽  
Scanning Electron

In this study, we present the process of synthesis FexNi1-xMn2O4 (x = 0; 0.1; 0.3; 0.5; 0.7; 0.9; 1) by method sol-gel. Scanning electron microscope results shows that the particle size is about 50 nm. The X-ray diffraction diagram shows that the samples are single phase, changing structure clearly as the x ratio increases from 0 to 1. The lattice constant, the bond length also changes with x-value as shown on the Raman scattering spectrum. The results of the vibrating sample magnetometer show that the magnetism of the material FexNi1-xMn2O4 changes with the value of x and reaches a maximum in the range x from 0.5 to 0.7.

scholarly journals Ferromagnetic Order in the Intermetallic Alloys laNi5-xMgx

2012 ◽  
Vol 29 (1) ◽  
pp. 50
Author(s):  
D.N Ba ◽  
L.T Tai ◽  
N.T Trung ◽  
N.T Huy
Keyword(s):  
Magnetic Properties ◽  
Curie Temperature ◽  
Room Temperature ◽  
Single Phase ◽  
Chemical Doping ◽  
Intermetallic Alloys ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ferromagnetic Order ◽  
Diffraction Patterns

The influences of the substitution of Ni with Mg on crystallographic and magnetic properties of the intermetallic alloys LaNi5-xMgx (x ≤ 0.4) were investigated. The X-ray diffraction patterns showed that all samples were of single phase, and the lattice parameters, a and c, decreased slightly upon chemical doping. LaNi5 is well known as an exchange-enhanced Pauli paramagnet. Interestingly, in LaNi5-xMgx, the ferromagnetic order existed even with a small amount of dopants; the Curie temperature reached the value of room temperature for x = 0.2, and enhanced with increasing x.

Analysis of Selected Area Diffraction Patterns With Winjade

1998 ◽  
Vol 4 (S2) ◽  
pp. 342-343 ◽  
Author(s):  
S. D. Walck ◽  
P. Ruzakowski-Athey
Keyword(s):  
Single Phase ◽  
Xrd Analysis ◽  
Analysis Program ◽  
X Ray Diffraction ◽  
Program Module ◽  
Vast Number ◽  
One Dimensional ◽  
X Ray ◽  
Diffraction Patterns ◽  
Xrd Patterns

The analysis of Selected Area Diffraction (SAD) patterns that are collected from a single phase material having sufficient crystallites to provide continuous rings is relatively straightforward. However, when this condition is not met and there may be several phases present having rings of a spotty nature, the pattern is complex and can be quite difficult to analyze manually because of the vast number of discrete spots. WinJade from MDI is an X-ray diffraction (XRD) analysis program with an Electron Diffraction Program Module (EDPM) that can be used to aid in the analysis of SAD patterns. The EDPM produces Integrated Circular Density Plots (ICDP), which are one-dimensional intensity profiles plotted as a function of equivalent XRD 20 values or crystal d-spacings. These ICDP's can be overlayed with XRD patterns or with reference lines from the NIST and JCPDS crystalline databases for direct comparisons.

Electrochemical Performance of La0.7Sr0.3Cu1-xFexO3-δ as Cathode Material in IT-SOFCs

2010 ◽  
Vol 160-162 ◽  
pp. 666-670
Author(s):  
Min Zhang Zheng ◽  
Xiao Mei Liu
Keyword(s):  
Electrical Conductivity ◽  
High Temperature ◽  
Cathode Material ◽  
Single Phase ◽  
Cathodic Polarization ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cathodic Overpotential ◽  
A Current

To obtain more detail information about the cathode of La0.7Sr0.3Cu1-xFexO3-δ（x= 0.1,0.3,0.5,0.7,0.9）in IT-SOFCs, the cathode material La0.7Sr0.3Cu1-xFexO3-δ（x=0.1, 0.3, 0.5, 0.7, 0.9）was synthesized by a sol-gel method. X-ray diffraction revealed it to be form a single phase of perovskite. The high temperature electrical conductivity was measured by using the four-point dc technique, and cathodic overpotential with SDC（Sm0.15Ce0.85O1.925） electrolyte support was measured by using a current-interruption technique. The investigation of electrocheimical properties suggested that La0.7Sr0.3Cu0.7Fe0.3O3-δ has the highest electrical conductivity and the lowest cathodic polarization. Using La0.7Sr0.3Cu0.7Fe0.3O3-δ as cathode and 65%NiO/SDC as anode based on SDC electrolyte one can obtain higher current density and power density at intermediate temperatures, La0.7Sr0.3Cu0.7Fe0.3O3-δ is considered to be a possible cathode adapted to IT-SOFCs.

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