scholarly journals Effect of Sb2O3 and/or CdO nanoparticle substitution on the properties of high-TC superconducting Bi1.6-x SbxPb0.4Sr2Ca2-yCdyCu3OZ material

2018 ◽  
Vol 16 (36) ◽  
pp. 73-84
Author(s):  
Sihama I. Salih
Keyword(s):  
High Temperature Superconductors ◽  
Partial Substitution ◽  
Partial Replacement ◽  
Flux Agent ◽  
High Tc ◽  
High Tc Phase ◽  
The Matrix ◽  
Zero Resistance ◽  
Xrd Patterns ◽  
Temperature Scanning

High temperature superconductors materials with composition Bi1.6-xSbxPb0.4Sr2Ca2-yCdyCu3OZ (x = 0, 0.1, 0.2 and 0.3) and (y = 0.01 and 0.02), were prepared by using the chemical reaction in solid-state ways, and test influence of partial replacement of Bi and Ca with Sb and Cd respectively on the superconducting properties, all samples were sintered at the same temperature (850 oC) and for the same time (195 h). The structural analysis of the prepared samples was carried out using X-ray diffraction (XRD) measurements performed at room temperature, scanning electron microscope (SEM) and dc electrical resistivity was measured as a function of temperature. It was found that the sample prepared by partial substitution of Sb at ratio (x= 0.2) and Cd with ratio (y=0.01), has the maximum value of zero resistance temperature, where was the TC(onset) and TC(0) values for this sample are (140 K) and (123 K) respectively, and XRD results reveal that this sample has the highest percentage of Bi- 2223 phase, as well as the analysis of XRD patterns of the prepared materials showed polycrystalline structure and signalize that all samples had an orthorhombic crystalline structure. It was concluded that Sb2O3 nanoparticles it may be acts as a flux agent in the matrix to lower the partial melting temperature of the samples and that leads to the promotion of the high-TC phase.

Preparation of Fibrous Bi(Pb)-Sr-Ca-Cu-O Crystals Containing the High-Tc Phase

1989 ◽  
Vol 169 ◽  
Author(s):  
I. Matsubara ◽  
H. Tanigawa ◽  
T. Ogura ◽  
H. Yamashita ◽  
M. Kinoshita ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Volume Fraction ◽  
Zero Magnetic Field ◽  
High Tc ◽  
X Ray ◽  
High Tc Phase ◽  
Zero Resistance ◽  
Resistance State ◽  
Oxygen Gas ◽  
T Phase

AbstractFibrous crystals containing the high-Tc phase (2223 phase) of the Bi(Pb)-Sr-Ca-Cu-O superconductor have been prepared by heating a glassy melt-quenched plate in a stream of oxygen gas. Each fiber is composed of several platelike single crystals which are stacked in a layered structure. The fibers show two stepdrops in resistance at 105K and 73K, and a zero-resistance state around 70K. From the results of SQUID measurements, the volume fraction of the high-T phase is found to be about 0.6%. The high-Tc phase is also detected with a microarea X-ray diffractometer, and it is stacked in the interlayer between the low-Tc platelike crystals. For the fibrous Bi-Sr-Ca-Cu-Li-O crystals, the volume fraction of the high-Tc phase increases to 1.5% and a zero resistance state is achieved at 81K. The Jc value of the Li doped fiber is 30,000A/cm2 at 77K and 300,000A/cm2 at 66K in a zero magnetic field.

Electron Microscopic study of modulated structure in a Bi-Pb-Sr-Ca-Cu-O system

1990 ◽  
Vol 48 (4) ◽  
pp. 86-87
Author(s):  
Akihiro Kumao ◽  
Shin’ichiro Uyeda ◽  
Hisamitsu Endoh
Keyword(s):  
Heat Treatment ◽  
Preparation Condition ◽  
Partial Substitution ◽  
Heating Process ◽  
Electron Microscopic ◽  
Modulated Structure ◽  
High Tc ◽  
High Tc Superconductor ◽  
Long Period ◽  
High Tc Phase

The preparation of high-Tc superconductor Bi-Sr-Ca-Cu-O is difficult because the strict heat treatment is requested. Takano et al. reported that the partial substitution of Pb for Bi in the system increases the volume of the high-Tc phase, namely it relieves the preparation condition of a superconductor both in the composition of starting materials and heating process. In this paper long-period structure and modulated structure in the Bi-Pb-Sr-Ca-Cu-O system is described.Powders of Bi2O3, PbO, SrCO3, CaCO3 and CuO, which were weighed such that the ratio of Bi:Pb:Sr: Ca:Cu = 0.96:0.15:1:1.1:1.6 (Sample 1), were dissolved in nitric acid. The compound produced by heating and evaporating solvent was ground in an agate mortar and heated in air at 800°C for 12h. After the reaction the mixture was ground again and made as a pellet, which was heated at 850°C for 48h. Other compositions, Bi:Pb:Sr:Ca:Cu = 0.96:0.24:1:1.1:1.6(Sample 2) and =0.7:0.3:1:1:1.8 (Sample 3), were also prepared with the same manner.

scholarly journals Superconductivity of BSCCO Compound Substituted Partially by Zr Nanoparticles at Bi Site

2021 ◽  
Vol 2114 (1) ◽  
pp. 012065
Author(s):  
A K Jassim ◽  
M M Abbas
Keyword(s):  
High Temperature Superconductors ◽  
Solid State Reaction Method ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
High Tc ◽  
Resistivity Measurements ◽  
High Tc Phase ◽  
Semiconductor Behavior ◽  
Method Effects ◽  
Two Phases

Abstract High-temperature superconductors with a nominal composition Bi2- xZrxPb0.4Sr2Ca2Cu3Oy for (0≤x≤0.3) were prepared by solid-state reaction method. Effects of the Zr nanoparticles substitution at Bi sites have been studied to obtain the optimum concentration for the formation and stabilization of the superconducting samples. Electrical resistivity measurements of the samples showed that the higher critical temperature TC was found at 118 K, which is for the composition Bi1.95Zr0.05Pb0.4Sr2Ca2Cu3Oy. Semiconductor behavior noticed for samples with concentration higher than 0.2. The X-ray diffraction results for all superconducting samples showed an orthorhombic structure with two phases, 2223 high-TC phase and 2212 low-TC phase. The scanning electron microscope has been used to identify the morphology of the superconducting phase. The plate-like grains of the high Bi-2223 phase appeared in most samples besides changes in morphology of the samples with increasing dopant concentration

scholarly journals Superconductivity Measurements of (Hg,Tl)-1223 Compound Prepared in Capsule

2021 ◽  
pp. 2934-2939
Author(s):  
B. A. Aljurani ◽  
G.Y. Hermiz ◽  
M.F. Alias
Keyword(s):  
Oxygen Content ◽  
Structural Investigation ◽  
Solid State Reaction Method ◽  
Lattice Parameter ◽  
Partial Substitution ◽  
Hole Doping ◽  
High Tc ◽  
High Tc Phase ◽  
Two Phases ◽  
Parameter Density

       In this paper, investigations were carried out on the effects of simultaneous partial substitution of Tl at the Hg site on the physical properties of an Hg1-xTlxBa2Ca2Cu3O8+δ cuprate superconductor with x= 0, 0.1, 0.2, 0.3 and 0.4. Two steps of the solid state reaction method were used to prepare samples in capsule. The results showed that the optimum sintering temperature was equal to 850 ᵒC and the sintering time was equal to 20 h for the prepared samples.       The best conditions for constitution and stabilization of the high Tc phase-1223 were obtained by investigating the effects of Tl substitution on Hg site and oxygen content (δ) on the superconducting properties.          Structural investigation revealed that all the samples have a tetragonal structure with two phases, namely an Hg-1223 high Tc phase as a main phase and an Hg-1212 low Tc phase. Besides, some impurity phases like CuO and CaHgO2 were found. The increase of Tl content in Hg1-xTlxBa2Ca2Cu3O8+δ compound from 0 to 0.4 caused a change in the lattice parameter, density of the unit cell (ρm), and c/a values.         HgBa2Ca2Cu3O8+δ compound exhibited a critical transition temperature that is equal to 115 K. On the other side, the results showed that the highest Tc was 119 K for Hg0.8Tl0.2 Ba2Ca2Cu3O8+δ. The oxygen content (δ= 0.46) was expected to be the optimum hole doping for Hg0.8Tl0.2 Ba2Ca2Cu3O8+δ compound, which  means in our opinion that  δ plays a remarkable role in the assessment of Tc.

Modulated structures in (Bi,Pb)-Sr-Ca-Cu-O films

1990 ◽  
Vol 48 (4) ◽  
pp. 62-63
Author(s):  
Shozo Ikeda ◽  
Hirotoshi Hayakawa ◽  
Daniel R. Dietderich
Keyword(s):  
Rf Magnetron Sputtering ◽  
Potential Method ◽  
High Tc ◽  
Bscco System ◽  
Heat Treated ◽  
Modulated Structures ◽  
High Tc Phase ◽  
Deposited Films ◽  
Sputtering System

Pb addition makes easier to form the high Tc phase in the BSCCO system. However, Pb easily vaporized at high temperature. A controlled Pb potential method has been applied to grow the high Tc phase in films. Initially, films are deposited on cleaved MgO substrates using an rf magnetron sputtering system. These amorphous as-deposited films are heat treated in a sealed gold capsule along with a large pellet of Pb-added BSCCO. Details of the process and characterization of the films have been reported elsewhere (1). Films trated for 0.5h at 850° C contain mainly the low Tc phase with a small amount of the high Tc phase. Hawever, films treated for 3h at 850°C consist mainly of the high Tc phase. This film is superconductive with a Tc(zero) of 106K. The Pb/Bi ratio of the films, analysed by SEM- EDS, are 0.12 and 0.18 for heat tratment times of 0.5 and 3h, respectively. The present study investigates the modulated structures of these films using HREM.

Synthesis and study the Structural and electrical and mechanical properties of High Temperature Superconductor Tl0.5Pb0.5Ba2Can-1Cun-xNixO2n+3-δ Substituted with nickel oxide for n=3

2018 ◽  
Vol 31 (3) ◽  
pp. 26 ◽  
Author(s):  
Laheeb. A. Mohammed ◽  
Kareem. A. Jasim
Keyword(s):  
Nickel Oxide ◽  
High Temperature Superconductor ◽  
Sintering Temperature ◽  
Concentration Effects ◽  
High Tc ◽  
Xrd Diffraction ◽  
Ni Content ◽  
High Tc Phase ◽  
Pure Phases ◽  
Critical Temperature Tc

   on this research is to study the effect of nickel oxide substitution on the pure phases superconductor Tl0.5Pb0.5Ba2Can-1Cun-xNixO2n+3-δ (n=3) where x=(0,0.2,0.4,0.6,0.8.and 1.0). The specimens in this work were prepared with used  procedure of solid state reaction with sintering temperature 8500C for 24 h .we used technical (4-prob)to calculated and the critical temperature Tc . The results of the XRD diffraction analysis showed that the structure for pure and doped phases was tetragonal with phases high-Tc phase (1223),(1212) and low-Tc phase (1202)  and add to the presence of some impure phase. It was noted the value a=b,c  the parameter of  the lattice increment  with the increment of Ni content. The increment of (NiO) concentration effects electrical resistivity, dielectric constant and the hardness.

STUDY OF THE DEPENDENCE OF HIGH Tc ON VARIOUS SINTERING TEMPERATURES FOR Bi-Pb-Sr-Ca-Cu-O SUPERCONDUCTORS

1991 ◽  
Vol 05 (24n25) ◽  
pp. 1635-1638
Author(s):  
S.M. M.R. NAQVI ◽  
A.A. QIDWAI ◽  
S.M. ZIA-UL-HAQUE ◽  
FIROZ AHMAD ◽  
S.D.H. RIZVI ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Liquid Nitrogen ◽  
X Ray Diffraction ◽  
High Tc ◽  
X Ray ◽  
Resistivity Measurements ◽  
Zero Resistance

Bi1.7-Pb0.3-Sr2-Ca2-Cu3-Ox superconducting samples were prepared at 855°C, 862 C, 870 C, and 882 C sintering temperatures respectively. All samples were sintered for 120 hours. The samples were then quenched in liquid nitrogen. The electrical resistivity measurements showed that the samples sintered at 870° C had the best Tc. For these samples the Tc onset was around 120 K and the zero resistance was obtained at 108 K. X-ray diffraction studies showed that the samples were multiphased.

Characterization of Epitaxial Superconducting YBacuO Thin Films with Three Different Orientations

1989 ◽  
Vol 169 ◽  
Author(s):  
X.K. Wang ◽  
D.X. Li ◽  
S.N. Song ◽  
J.Q. Zheng ◽  
R.P.H. Chang ◽  
...  
Keyword(s):  
Thin Films ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Orientation Dependence ◽  
Zero Field ◽  
Epitaxial Thin Films ◽  
Oriented Film ◽  
Zero Resistance ◽  
Xrd Patterns

AbstractEpitaxial thin films of YBaCuO were prepared by multilayer deposition from Y, Cu, and BaF2 sources with: (1) the a‐axis perpendicular to (100)SrTiO3; (2) the c‐axis perpendicular to (100)SrTiO3; and (3) the [110] axis perpendicular to (110)SrTiO3. XRD patterns as well as SEM and HREM images confirm that the films are highly oriented, essentially epitaxial. Both the a‐axis oriented and the c‐axis oriented films exhibit zero resistance at 91K. The [110] oriented film shows the sharpest transiton with a transition width of IK and zero resistance at 85K. The zero field critical current density, Jc, determined magnetically, is in excess of 107A/cm2 at 4.4K and 1.04 x 106A/cm2 at 77K for the c‐axis oriented film; for the a‐axis oriented film we obtained 6.7 x 106A/cm2 at 4.4K and 1.2 x 105A/cm2 at 77K. The orientation dependence of the critical current density in the basal plane of the a‐axis oriented film was studied. The largest Jc's occur along the in‐plane <100> axes of the substrate.

OBSERVATION OF THE ESR FOR HIGH-Tc SUPERCONDUCTORS Bi-Sr-Ca-Cu-O

1989 ◽  
Vol 03 (04) ◽  
pp. 355-359 ◽  
Author(s):  
S.L. YUAN ◽  
B.H. HOU ◽  
S.Z. JIN ◽  
W. WANG ◽  
G.G. ZHENG ◽  
...  
Keyword(s):  
Superconducting Transition ◽  
Teller Distortion ◽  
High Tc ◽  
Spin Resonance ◽  
Jahn Teller ◽  
Zero Resistance ◽  
Magnetic Ions ◽  
Preliminary Study ◽  
Perpendicular Component ◽  
Jahn Teller Distortion

The preliminary study on the electron spin resonance (ESR) for the Bi-Sr-Ca-Cu-O system with different superconducting transition temperatures has been made at room temperature. It is found that the Lande factor g-values are increased with increasing zero resistance temperature T c0 but width between peaks ΔH pp of the ESR spectrum decreased with increasing T c0 . These might be attributed to the spin-orbit coupling of the magnetic ions and the Jahn-Teller distortion in the perpendicular component.

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