Effects of Donor Doping on Microstructure and Electrical Properties of Bismuth Layer-Structured Bi4Ti3O12 Ceramics

2007 ◽  
Vol 280-283 ◽  
pp. 259-262 ◽  
Author(s):  
Lina Zhang ◽  
Su Chuan Zhao ◽  
Liao Ying Zheng ◽  
Guo Rong Li ◽  
Qing Rui Yin
Keyword(s):  
Electrical Conductivity ◽  
High Temperature ◽  
Electrical Properties ◽  
Ferroelectric Properties ◽  
Orthorhombic Phase ◽  
X Ray Diffraction ◽  
Suitable Candidate ◽  
X Ray ◽  
Donor Doping ◽  
Diffraction Patterns

A study was conducted on the effects of donor dopants, Nb2O5 and WO3, on microstructure and electric properties of Bi4Ti3O12 (BIT) ceramics. X-ray diffraction patterns of the materials showed a single orthorhombic phase structure. The microstructure results revealed the appearance of plate-like grain. The donor doping decreased the conductivity of BIT by as much as 3 orders of magnitude. The dielectric and ferroelectric properties of doped-BIT materials were also investigated. The decrease in the electrical conductivity allowed the doped samples to be poled to develop piezoelectricity. Thermal annealing studies of the samples indicated the donor-doped BIT were suitable candidate materials for high-temperature piezoelectric applications.

STRUCTURE-PROPERTIES RELATION OF CO-DOPE BISMUTH LAYER-STRUCTURED Bi3.25La0.75(Ti1-xWx)3O12 CERAMICS

2009 ◽  
Vol 23 (31n32) ◽  
pp. 3793-3799
Author(s):  
PASINEE SIRIPRAPA ◽  
ANUCHA WATCHARAPASORN ◽  
SUKANDA JIANSIRISOMBOON
Keyword(s):  
Electrical Conductivity ◽  
Dielectric Constant ◽  
Lattice Distortion ◽  
Ferroelectric Properties ◽  
Doping Content ◽  
Orthorhombic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Structure Properties

In this work, fabrication and investigation of substituing high-valence W 6+ for Ti 4+ ion on B -site of La 3+-doped Bi 4 Ti 3 O 12 or BLT structure to form Bi 3.25 La 0.75( Ti 1-x W x)3 O 12 or BLTW (when x = 0, 0.01, 0.03, 0.05 0.07, 0.09 and 0.10) ceramics were carried out. X-ray diffraction patterns of BLTW ceramics indicated orthorhombic structure with lattice distortion, especially with higher concentration of WO 3 dopant. An increase in WO 3 doping content reduced not only length and thickness of grain, but also density of the ceramics. Electrical conductivity was found to decrease, while dielectric constant increased with W 6+ doping. Ferroelectric properties were found to be improved with increasing WO 3 content and were optimized at x = 0.05.

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.

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.

Effect of Sintering Temperature on Silver-Copper Nanopaste as High Temperature Die Attach Material

2013 ◽  
Vol 795 ◽  
pp. 47-50 ◽  
Author(s):  
Kim Seah Tan ◽  
Kuan Yew Cheong
Keyword(s):  
Electrical Conductivity ◽  
High Temperature ◽  
Sintering Temperature ◽  
Grain Structure ◽  
Binder System ◽  
X Ray Diffraction ◽  
X Ray ◽  
Silver Copper ◽  
Die Attach ◽  
Scanning Electron

A novel stencil-printable silver-copper (Ag-Cu) nanopaste that serves as an alternative high temperature die attach material was introduced in this study. The nanopaste was made by mixing 50 nm-sized of Ag and Cu particles with an organic binder system. Sintering temperatures, up to 450°C, were used to sinter nanopaste in air and its post sintered properties were investigated. The viscosity of nanopaste was 350,000 cps and it demonstrated a shear thinning behavior. Scanning electron microscope revealed the change of grain structure with the change in the sintering temperature. Formations of Ag97Cu3 and Ag1Cu99 compounds after sintering were confirmed with X-ray diffraction; and the electrical conductivity of the sintered nanopaste was increased with the increase of the sintering temperature. The study concluded 380°C was the optimum sintering temperature to form a well sintered nanopaste.

X-ray Diffraction and Modelling Studies of Multilayer SnO2 Thin Film Gas Sensors

1995 ◽  
Vol 403 ◽  
Author(s):  
L. E. Depero ◽  
C. Perego ◽  
L. Sangaletti ◽  
G. Sberveglieri
Keyword(s):  
Thin Film ◽  
Orthorhombic Phase ◽  
Sno2 Thin Film ◽  
X Ray Diffraction ◽  
X Ray ◽  
Modelling Studies ◽  
Cation Coordination ◽  
Diffraction Patterns ◽  
Two Phases ◽  
The Relationship

AbstractStructural studies have been carried out on SnO2 multilayer thin film grown by the Rheotaxial Growth and Thermal Oxidation method on A120 3 substrates. A preliminary analysis of the X-ray diffraction patterns shows that, in addition to the Sn0 2 cassiterite phase, a strong contribution from an orthorhombic Sn02 phase is present.In the case of the 3-layer film, the orthorhombic phase is structurally and microstructurally stable after an annealing up to 32 h at 400 'C. The cation coordination is similar to that found in cassiterite, but the chains of edge-sharing [SnO6]8- octahedra run in a zig-zag fashion along the [100] direction, each straight unit containing four octahedra. The relationship between the two phases is discussed on the basis of structural simulations including twinning planes in the crystal structure.

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.

Structure, magnetic and electrical properties of Ln2/3Pb1/3MnO3 (Ln = La, Pr, Nd) films

2008 ◽  
Vol 86 (6) ◽  
pp. 829-833
Author(s):  
L A Han ◽  
C L Chen
Keyword(s):  
Electrical Properties ◽  
Double Exchange ◽  
Orthorhombic Phase ◽  
Rf Magnetron Sputtering ◽  
Metallic State ◽  
X Ray Diffraction ◽  
X Ray ◽  
Jahn Teller ◽  
Higher Temperature ◽  
Ion Radius

Ln2/3Pb1/3MnO3 (Ln = La, Pr, Nd) films deposited on single crystal LaAlO3 substrate were fabricated using the RF magnetron sputtering method. The X-ray diffraction results of bulk targets indicate that with the decrease of the average ion radius < rA >, the structure transits from the rhombohedral to the orthorhombic phase. The magnetic properties show that there is a transition from the ferromagnetic to the paramagnetic state with the increase in temperature, the Curie temperature reduces abruptly with the decrease of < rA >. The electrical properties show that films are in the metallic state, which can be fitted to the formula: ρ(T) = ρ0 + ρ1T2 + ρ2T4.5 at low temperatures and the insulator state, which can be fitted to the formula: ρ(T) = ρ0T exp(Ea/KBT) at higher temperature(T > TMI). The temperature range of the ferromagnetic metallic state becomes narrow with the decrease of < rA >. The phenomenon can be qualitatively and reasonably explained by the double-exchange model and Jahn–Teller effects. PACS Nos.: 75.47.Lx, 74.25.Ha, 75.47.–m, 75.30.Et

scholarly journals Electrical Conductivity and Chemical Equilibria of Coordination Biopolymeric Cerium (IV)-Alginate Complex with Correlation between the Structure and Complex Stability

2015 ◽  
Vol 7 (2) ◽  
pp. 57 ◽  
Author(s):  
Ishaq Zaafarany ◽  
Hatem Altass ◽  
Jabir Alfahemi ◽  
Khalid Khairou ◽  
Refat Hassan
Keyword(s):  
Electrical Conductivity ◽  
Conduction Mechanism ◽  
Research Study ◽  
Coordination Geometry ◽  
Complex Stability ◽  
X Ray Diffraction ◽  
Chemical Equilibria ◽  
X Ray ◽  
Infrared Absorption Spectra ◽  
Diffraction Patterns

In this research study, the cross-linked cerium (IV)-alginate complex, as coordination biopolymeric compound in the granules form, was prepared. It has been indicated from the x-ray diffraction patterns that the nature of alginate complex is amorphous. Additionally, it has been revealed from the infrared absorption spectra that cerium (IV) chelates the alginate macromolecular chains in the complex. The study has displayed that the range of us OCO- is 1424 cm-1and the range of uasOCO- is 1605 cm-1. This indicates that a complexation type between the cation Ce4+ and both carboxylate and hydroxyl functional groups of alginate macromolecule is usually takes place. The study has also measured the electrical conductivity (s) of coordination biopolymeric cerium (IV)-alginate complex, as function of temperature. It has been indicated from the measured value of the electrical conductivity, i.e., 1.04 x10-9 Siemens at 20oC that the conductance of the complex lies in the range of semiconductors. The research has profoundly discussed with evaluation of the thermodynamic parameters. Afterwards, appropriate conduction mechanism based on the electrical conductivity and chemical equilibrium has also been suggested and discussed in terms of the complex stability in correlation with its coordination geometry.

Electrical Properties of Modified BNT Based Lead-Free Ceramics

2016 ◽  
Vol 872 ◽  
pp. 87-91
Author(s):  
Supalak Manotham ◽  
Tawee Tunkasiri ◽  
Pharatree Jaita ◽  
Pichitchai Butnoi ◽  
Denis Russell Sweatman ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Solid State ◽  
Electrical Properties ◽  
Sintering Temperature ◽  
Ferroelectric Properties ◽  
Lead Free ◽  
Second Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lead Free Ceramics

The properties of modified Bi0.5Na0.5TiO3 (BNT) based lead-free ceramics were investigated. The BNT-based ceramics were prepared by a solid-state mixed oxide method Phase formation was determined by X-ray diffraction technique (XRD). The X-ray diffraction analysis of the ceramics suggested that all samples exhibited a perovskite structure without second phase. The value of dielectric constant increased with increasing in sintering temperature. Moreover, high sintering temperatures could improve ferroelectric properties of BNT base lead-free ceramics.

Sign in / Sign up

Export Citation Format

Share Document