Structural and electrical properties of pure and doped lanthanum oxide

2021 ◽  
pp. 2150210
Author(s):  
Nazma D. Dal ◽  
Nisha N. Chavda ◽  
Parul H. Madhad ◽  
Ramesh Kumar ◽  
Neeta A. Bhammar ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Power Law ◽  
Relaxation Mechanism ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Frequency Dependent ◽  
Plot Analysis ◽  
Dielectric Constant And Loss ◽  
Structural And Electrical Properties ◽  
Xrd Patterns

In this communication, structural and electrical properties of rare earth oxides La2O3 (LO) and LaNdO3 (LNO) have been studied. To understand the structural properties of the LO and LNO samples, X-ray diffraction (XRD) measurement was carried out at room temperature. The XRD patterns have been analyzed by Rietveld refinement to confirm the single-phase nature of both the samples. The crystal structures of studied samples were created from the derived parameters of Rietveld parameters. The crystal size and lattice strain have been estimated using Williamson–Hall (W–H) plot analysis. Frequency-dependent dielectric constant and loss tangent have been studied for a frequency range of 20 Hz to 2 MHz. To estimate the relaxation time and contribution of the charge carriers in the studied samples, relaxation mechanism and universal dielectric response (UDR) model have been employed. The ac conductivity measurements were carried out for the same frequency range (i.e., 20 Hz to 2 MHz) which has been understood on the basis of Jonscher’s power law. The barrier height has been calculated by fitting the power law. Frequency-dependent impedance behavior has been discussed in the context of grains and grain boundaries for both the samples under study.

scholarly journals Structural and Electrical Properties of Silicon Nitride Ceramic

1970 ◽  
Vol 7 (1) ◽  
pp. 50-59 ◽  
Author(s):  
M Hosneara ◽  
A Hasnat ◽  
AH Bhuyan
Keyword(s):  
Weight Gain ◽  
Silicon Nitride ◽  
Electrical Properties ◽  
Structural Properties ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
Silicon Nitride Ceramic ◽  
Structural And Electrical Properties ◽  
Xrd Patterns ◽  
Good Agreement

The effects of structural properties on the d.c. and a.c. electrical properties of different weight gain reaction bonded silicon nitride (RBSN) have been studied in this work. The degree of nitridation is assessed by the ‘weight gain’ of the ceramic, the percentage by which the weight is increased in the nitriding reaction. From X-ray diffraction (XRD) patterns, it is observed that a higher degree of nitradation sample has strong α-silicon nitride peaks. Intensity of α-silicon nitride peaks decreases with decreases weight gain. The higher degrees of nitridation, the samples have less significant Si peak. XRD patterns were recorded to calculate the lattice parameters of RBSN. The lattice parameters for three weight gain RBSN samples are found to be a =b = 7.7727 Å, c= 5.6565 Å (26% weight gain), a=b= 7.6272 Å, c= 5.6374 Å (42% weight gain) and a=b=7.6158 Å, c= 5.7732 Å (58.27% weight gain) and are in good agreement with the reported values from XRD patterns. Porosity (%) and surface morphology was observed by SEM. Keywords: Silicon nitride ceramic; electrical properties; structural properties.   DOI: http://dx.doi.org/10.3329/diujst.v7i1.9648   Daffodil International University Journal of Science and Technology Vol.7(1) 2012 50-58

scholarly journals Structural and electrical properties of chromium substituted nickel ferrite by conventional ceramic method

2016 ◽  
Vol 34 (1) ◽  
pp. 185-191 ◽  
Author(s):  
Nusrat Jahan ◽  
Faruque-uz-Zaman Chowdhury ◽  
A.K.M Zakaria
Keyword(s):  
Dc Resistivity ◽  
X Ray Diffraction ◽  
Ceramic Method ◽  
X Ray ◽  
Dielectric Constant And Loss ◽  
Structural And Electrical Properties ◽  
Ray Density ◽  
Cr Concentration ◽  
Xrd Patterns ◽  
Increasing Temperature

AbstractPolycrystalline Cr substituted Ni ferrites [NiCrxFe2−xO4(0.0 ≤ x ≤ 1.0)] were synthesized by conventional ceramic method and sintered at 1350 °C in air. X-ray diffraction (XRD) patterns showing sharp peaks confirmed the formation of single phase cubic spinel structure. The lattice parameters of the samples were determined from the XRD data using Nelson-Riley extrapolation technique. They were found to decrease with increasing Cr concentration obeying Vegard’s law. X-ray density, bulk density and porosity were also calculated from the XRD data. The variation of DC resistivity with temperature was measured by two-probe method. The DC resistivity was found to decrease with increasing temperature indicating the semiconducting nature of the samples. Activation energy was calculated from the Arrhenius plot. AC resistivity, dielectric constant and loss tangent were measured in the frequency range of 1 kHz to 120 MHz at room temperature.

Fabrication and study the effect of the laser on the properties of the compound Tl2-xHgxBa2-ySryCa2Cu3O10+δ superconductor

2018 ◽  
pp. 168
Author(s):  
A. Kareem Dahash Ali ◽  
Nihad Ali Shafeek
Keyword(s):  
Transition Temperature ◽  
Solid State ◽  
Hydrostatic Pressure ◽  
Electrical Properties ◽  
Co2 Laser ◽  
Temperature Shift ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural And Electrical Properties

This study included the fabrication of    compound (Tl2-xHgxBa2-ySryCa2Cu3O10+δ) in a manner solid state and under hydrostatic pressure ( 8 ton/cm2) and temperature annealing(850°C), and determine the effect of the laser on the structural and electrical properties elements in the compound, and various concentrations of x where (x= 0.1,0.2,0.3 ). Observed by testing the XRD The best ratio of compensation for x is 0.2 as the value of a = b = 5.3899 (A °), c = 36.21 (A °) show that the installation of four-wheel-based type and that the best temperature shift is TC= 142 K  .When you shine a CO2 laser on the models in order to recognize the effect of the laser on these models showed the study of X-ray diffraction of these samples when preparing models with different concentrations of the values ​​of x, the best ratio of compensation is 0.2 which showed an increase in the values ​​of the dimensions of the unit cell a=b = 5.3929 (A °), c = 36.238 (A°). And the best transition temperature after shedding laser is TC=144 K. 

Effects of Different Sintering Temperature on the Microstructure and Piezoelectric Properties of Pb(Nb2/3Zn1/3)x(Zr52Ti48)1-XO3 Ceramics

2014 ◽  
Vol 1061-1062 ◽  
pp. 83-86
Author(s):  
Hong Wu ◽  
De Yi Zheng
Keyword(s):  
Electrical Properties ◽  
Electromechanical Coupling ◽  
Piezoelectric Properties ◽  
Sintering Temperature ◽  
Electromechanical Coupling Coefficient ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ceramic Samples ◽  
Xrd Patterns ◽  
The Relationship

In this paper, the effects of different sintering temperature on the microstructure and piezoelectric properties of Pb(Nb2/3Zn1/3)0.03(Zr52Ti48)0.97O3(PNZZT) ceramic samples were investigated. The Pb(Nb2/3Zn1/3)0.03(Zr52Ti48)0.97O3 ceramics materials was prepared by a conventional mixed oxide method. In the period of the experiment, the relationship between crystallographic phase and microstructure were analyzed by X-ray diffraction(XRD) and scanning electron microscopy(SEM) respectively. The XRD patterns shows that all of the ceramic samples are with a tetragonal perovskite structure. Along with sintering temperature increased and the x is 0.03, the grain size gradually become big. Through this experiment, it has been found that when the x is 0.03 and sintered at 1130°C for 2 h, the grains grow well, the grain-boundary intersection of the sample combined well and the porosity of the ceramics decreased, an excellent comprehensive electrical properties of the Pb(Nb2/3Zn1/3)0.03(Zr52Ti48)0.97O3 samples can be obtained. Its best electrical properties are as follows: dielectric constant (ε) is 1105, dielectric loss(tg) is 0.017, electromechanical coupling coefficient (Kp) is 0.287, piezoelectric constant(d33) is 150PC/N

Effect of TiO2 Nanoparticle on the Structural and Electrical Properties of Nd0.67Sr0.33MnO3 /TiO2 Composites

2021 ◽  
Vol 317 ◽  
pp. 60-65
Author(s):  
Kean Pah Lim ◽  
Lik Nguong Lau ◽  
Amirah Natasha Ishak ◽  
Mohd Mustafa Awang Kechik ◽  
Soo Kien Chen ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Grain Boundary ◽  
Double Exchange ◽  
Secondary Phase ◽  
Solid State Reaction Method ◽  
Peak Shift ◽  
Boundary Region ◽  
Structural And Electrical Properties ◽  
Xrd Patterns ◽  
Grain Surface

In this work, (1-x) (Nd0.67Sr0.33MnO3): x (TiO2) composites with x = 0, 0.1, 0.2, 0.3 and 0.4 have been prepared to investigate the structural and electrical properties. Nd0.67Sr0.33MnO3 (NSMO) was synthesised via the solid-state reaction method before incorporated with TiO2. The addition of TiO2 nanoparticle as the secondary phase in manganite composite would favour the spin-polarized tunnelling near to the grain boundary and thus enhance the extrinsic magnetoresistance. Nevertheless, nanoparticle addition might contribute to substitution and diffusion with manganite compound as reported in literature. The effect of the TiO2 nanoparticle addition into NSMO composites has been examined by an X-ray diffractometer (XRD) and a four-point probe (4PP) system. From the thermogravimetric analysis (TGA), NSMO phase formation occurred in between 756.45 - 977.59 °C. XRD patterns showed that there is no peak shift when the TiO2 concentration increases. It can be deduced that TiO2 was segregated at the NSMO grain boundary region and its grain surface. However, a small amount of Ti atoms are expected to replace the Mn atoms in NSMO crystal system and has caused the increase in crystallite size. The electrical study showed that the presence of TiO2 nanoparticle and substitution of Ti in Mn sites have weaken the double exchange (DE) mechanism and suppressed the metal-insulator transition temperature (TMI). In addition, the insulating behaviour of TiO2 has also caused the resistivity of composites to increase drastically.

Structural and Electrical Properties of La0.7Ca0.3MnO3 /α-Fe2O3 Composites

2021 ◽  
Vol 317 ◽  
pp. 66-71
Author(s):  
Lik Nguong Lau ◽  
Kean Pah Lim ◽  
Amirah Natasha Ishak ◽  
Mohd Mustafa Awang Kechik ◽  
Soo Kien Chen ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Sol Gel ◽  
Parent Compound ◽  
Mixed Valence ◽  
Space Group ◽  
Colossal Magnetoresistive ◽  
Structural And Electrical Properties ◽  
Modern Application ◽  
Xrd Patterns ◽  
Insulating Phase

Colossal magnetoresistive (CMR) materials have huge potential in modern application and it has been widely used in magnetic sensing industry. From the literature, an incorporation of secondary insulating phase into mixed-valence manganites could improve its extrinsic effect especially low-field magnetoresistance (LFMR). However, nanoparticle addition could lead to substitution and diffusion with its parent compound. In this work, the structural and electrical properties of La0.7Ca0.3MnO3 (LCMO) were investigated by adding the α-Fe2O3 nanoparticle with ratio of 0.00, 0.05, 0.10, 0.15 and 0.20 as the artificial grain boundaries. The LCMO compound has been synthesised using sol-gel route. The samples were chosen to sinter at 800°C to obtain the pure LCMO phase by referring to the thermogravimetric analysis (TGA). The structural properties were investigated by an X-ray diffractometer (XRD) while electrical properties were measured by a four-point probe (4PP) system. XRD patterns showed the coexistence of two phases (LCMO & α-Fe2O3). LCMO crystallised in orthorhombic structure with space group Pnma while α-Fe2O3 exhibited in hexagonal form with space group R-3c. As the content of α-Fe2O3 increases, the resistivity of the samples increases drastically. Nevertheless, the addition of iron oxide has no significant effect on the metal-insulator transition temperature (T­MI). From the XRD and 4PP analysis, it can be deduced that the α-Fe2O3 nanoparticles do not react with LCMO compound and successfully formed the La0.7Ca0.3MnO3 /α-Fe2O3 composites. The resistivity increases when the nano-sized α-Fe2O3 is added into LCMO nanocomposites due to the insulator nature of α-Fe2O3.

Structural and Electrical Properties of Colossal Magnetoresistive LSMO Thin Films Prepared by KrF Laser Ablation Method

2001 ◽  
Vol 666 ◽  
Author(s):  
Fumiaki Mitsugi ◽  
Tomoaki Ikegami ◽  
Kenji Ebihara ◽  
Jagdish Narayan ◽  
Alexander M. Grishin
Keyword(s):  
Thin Films ◽  
Laser Ablation ◽  
Electrical Properties ◽  
Lattice Mismatch ◽  
X Ray Diffraction ◽  
Axis Orientation ◽  
X Ray ◽  
Colossal Magnetoresistive ◽  
Laser Ablation Method ◽  
Structural And Electrical Properties

ABSTRACTWe prepared colossal magnetoresistive La0.8Sr0.2MnO3 thin films on the MgO, SrTiO3 and LaAlO3 single crystal substrates using KrF excimer pulsed laser ablation technique. The structural and electrical properties of the La0.8Sr0.2MnO3 thin films which were strained by the lattice mismatch are reported. The in-plane lattice mismatch between the La0.8Sr0.2MnO3 and MgO, SrTiO3 and LaAlO3 substrates are -7.8 %, -0.5 % and +2.3 %, respectively. The X-ray diffraction spectra of the films exhibited c-axis orientation. In the case of the La0.8Sr0.2MnO3 / LaAlO3 thin films with thickness over 100 nm, the divided (00l) peaks were observed. The surface morphology and transport property of the strongly stressed La0.8Sr0.2MnO3 / LaAlO3 were different from those of La0.8Sr0.2MnO3 / MgO and La0.8Sr0.2MnO3 / SrTiO3thin films.

Investigations on the Structural, Optical and Dielectric Properties of Ball-Milled ZnO–Fe2O3 Nanocomposites

2020 ◽  
Vol 19 (04) ◽  
pp. 1950034
Author(s):  
V. Balachandar ◽  
J. Brijitta ◽  
K. Viswanathan ◽  
R. Sampathkumar
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Ball Milling ◽  
High Energy ◽  
X Ray Diffraction ◽  
Dielectric Constant And Loss ◽  
Energy Ball ◽  
Uv Visible ◽  
Ball Milling Technique ◽  
Xrd Patterns

In this study, ZnO–Fe2O3 nanocomposites were prepared by high-energy ball milling technique and characterized through X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), UV–visible spectroscopy and dielectric spectroscopy. The amount of Fe2O3 in the ZnO–Fe2O3 nanocomposites was varied at the rates of 1[Formula: see text]wt.%, 3[Formula: see text]wt.% and 5[Formula: see text]wt.% in order to investigate its influence on the structural, optical and dielectric properties of the nanocomposites. XRD patterns of nanocomposites revealed no shift in peak positions and hence confirmed the formation of composites after ball milling. Further, it was observed from FESEM analysis that Fe2O3 particles were distributed randomly on the ZnO matrix of the nanocomposites. ZnO–Fe2O3 nanocomposites reveal extended optical absorption in the range of 400–600[Formula: see text]nm from UV studies. The dielectric constant and loss of the nanocomposites decrease exponentially with increase in frequency. The composition and frequency dependences of the dielectric constant, dielectric loss and AC conductivity are explained based on the Maxwell–Wagner effect and Koop’s theory.

Structural and electrical properties of Cu-doped Ni–Zn nanocrystalline ferrites for MLCI applications

2017 ◽  
Vol 31 (33) ◽  
pp. 1750318 ◽  
Author(s):  
D. Venkatesh ◽  
K. V. Ramesh
Keyword(s):  
Electrical Properties ◽  
Cation Distribution ◽  
Tetrahedral Site ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Structural And Electrical Properties ◽  
Phase Spinel ◽  
Diffraction Patterns

Polycrystalline Cu substituted Ni–Zn ferrites with chemical composition Ni[Formula: see text]Zn[Formula: see text]-Cu[Formula: see text]Fe2O4 (x = 0.00 to 0.25 in steps of 0.05) have been prepared by citrate gel autocombustion method. The samples for electrical properties have been sintered at 900[Formula: see text]C for 4 h. The X-ray diffraction patterns of all samples indicate the formation of single phase spinel cubic structure. The value of lattice parameter is decreases with increasing Cu concentration. The estimated cation distribution can be derived from X-ray diffraction intensity calculations and IR spectra. The tetrahedral and octahedral bond lengths, bond angles, cation–cation and cation–anion distances were calculated by using experimental lattice parameter and oxygen positional parameters. It is observed that Cu ions are distributed in octahedral site and subsequently Ni and Fe ions in tetrahedral site. The grain size of all samples has been calculated by Scanning Electron Microscopy (SEM) images. The variations in DC electrical resistivity and dielectric constant have been explained on the basis of proposed cation distribution.

Non-Stoichiometry and Structure of SrCe1-xYbxO3 Perovskite-Type Oxides

1996 ◽  
Vol 453 ◽  
Author(s):  
Igor Kosacki ◽  
Mark Shumsky ◽  
Harlan U. Anderson
Keyword(s):  
Electrical Conductivity ◽  
Electrical Properties ◽  
Charge Carrier ◽  
Structural Properties ◽  
Electrical Transport ◽  
Structural Disorder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural And Electrical Properties ◽  
Perovskite Type

AbstractThe structural and electrical properties of SrCe1-xYbxO3 ceramics have been studied as a function of temperature and Yb-concentration using x-ray diffraction and impedance techniques. The influence of Yb-dopants on electrical transport and structural disorder has been studied. A correlation between the structural properties, electrical conductivity is observed and discussed. These measurements allow us to determine the mechanism of charge carrier compensation and also the concentration and mobility of the electrical species.

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