Investigate Oxygen Content in YBa2Cu3O7-δ Superconductors

2014 ◽  
Vol 979 ◽  
pp. 124-127 ◽  
Author(s):  
Thitipong Kruaehong

The YBa2Cu3O7-δ(Y123) compounds were synthesized by solid state reaction method. The home-made four-probes apparatus was used for the resistivity measurement. The highest Tc is 91.95 K in sample C and sample A has lowest Tc onset at 89.85 K. The crystal structure properties and oxygen content were characterized by powder X-ray diffraction using CuKα radiation (λ=1.5406 Å). The Pmmm and Pnma space group corresponding on the superconducting phase and the non-superconducting phase. The atomic position of samples were consisted of various element atom. The longer time of oxygen-doping, the increase the critical temperature , superconducting phase and c lattice parameters.

Author(s):  
Hongqiang Cui ◽  
Yongze Cao ◽  
Lei Zhang ◽  
Yuhang Zhang ◽  
Siying Ran ◽  
...  

Er3+ with different concentrations doped K2Yb(PO4)(MoO4) phosphors were prepared by a solid-state reaction method, and the layered orthorhombic crystal structure of the samples was confirmed by X-ray diffraction (XRD). Under...


2021 ◽  
Vol 11 (15) ◽  
pp. 6760
Author(s):  
Heeju Ahn ◽  
Eunjeong Lee ◽  
Yujin Cho ◽  
Dongyeon Bae ◽  
Hee Jung Park ◽  
...  

We synthesized Sr- and W-doped BaTiO3 (BTO) polycrystals by using a solid-state reaction method. The X-ray diffraction results showed that Sr and W atoms occupied the Ba and Ti sites in tetragonal BTO, respectively, and there were changes in the lattice constants and the volumes in the Sr- and W-doped BTO. We found a change in the latent heat and the Curie temperature (TC) during the transition between the ferroelectric and paraelectric phases while increasing the contents of Sr and W in the Sr- and W-doped BTO. This can be explained by the fact that the doping of Sr and W atoms in BTO prevented a distinct transition between the ferroelectric tetragonal and paraelectric cubic structures by decreasing the c/a ratio to a value close to unity. This study shows a way toward a strategy for modulating a crystal structure by using proper dopants for future applications in ferroelectricity-based devices.


2016 ◽  
Vol 840 ◽  
pp. 48-51
Author(s):  
Muhammad Nor Azri Aziz ◽  
Johar Banjuraizah ◽  
Shing Fhan Khor ◽  
Zainal Arifin Ahmad

La0.8Sr0.2MO3+δ, (M=Mn, Fe, Cr, Co) ceramics were prepared by using solid state reaction method. All raw materials were mixed and ground using mortar. Homogenized powders were calcined at 900°C for three hour followed by grounding and uniaxial pressed at 100MPa. Compacted pellets were further pressed using cold isostatic pressing machine at 2600kg/m.s and sintered at 1300°C with heating rate 5°C/min for 4 hour. Crystal structure and phase transformation of sintered samples were obtained using X-ray diffraction. Density and porosity are measured by using Archimedes principle. The morphology of sintered samples is observed using scanning electron microscopy, while elemental analysis using the EDX.


2016 ◽  
Vol 34 (2) ◽  
pp. 412-417
Author(s):  
Esra Öztürk

AbstractIn this work, aluminate type phosphorescence materials were synthesized via the solid state reaction method and the photoluminescence (PL) properties, including excitation and emission bands, were investigated considering the effect of trace amounts of activator (Eu3+) and co-activator (Dy3+). The estimated thermal behavior of the samples at certain temperatures (> 1000 °C) during heat treatment was characterized by differential thermal analysis (DTA) and thermogravimetry (TG). The possible phase formation was characterized by X-ray diffraction (XRD). The morphological characterization of the samples was performed by scanning electron microscopy (SEM). The PL analysis of three samples showed maximum emission bands at around 610 nm, and additionally near 589 nm, 648 nm and 695 nm. The bands were attributed to typical transitions of the Eu3+ ions.


2015 ◽  
Vol 5 (01) ◽  
pp. 31
Author(s):  
Resky Irfanita ◽  
Asnaeni Ansar ◽  
Ayu Hardianti Pratiwi ◽  
Jasruddin J ◽  
Subaer S

The objective of this study is to investigate the effect of sintering temperature on the synthesis of SiC produced from rice husk ash (RHA) and 2B graphite pencils. The SiC was synthesized by using solid state reaction method sintered at temperatures of 750°C, 1000°C and 1200°C for 26 hours, 11.5 hours and 11.5 hours, respectively. The quantity and crystallinity level of SiC phase were measured by means of Rigaku MiniFlexII X-Ray Diffraction (XRD). The microstructure of SiC was examined by using Tescan Vega3SB Scanning Electron Microscopy (SEM). The XRD results showed that the concentration (wt%) of SiC phase increases with the increasing of sintering temperature. SEM results showed that the crystallinity level of SiC crystal is improving as the sintering temperature increases


2016 ◽  
Vol 10 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Mohamed Afqir ◽  
Amina Tachafine ◽  
Didier Fasquelle ◽  
Mohamed Elaatmani ◽  
Jean-Claude Carru ◽  
...  

SrBi1.8Ce0.2Nb2O9 (SBCN) and SrBi1.8Ce0.2Ta2O9 (SBCT) powders were prepared via solid-state reaction method. X-ray diffraction analysis reveals that the SBCN and SBCT powders have the single phase orthorhom-bic Aurivillius structure at room temperature. The contribution of Raman scattering and FTIR spectroscopy of these samples were relatively smooth and resemble each other. The calcined powders were uniaxially pressed and sintered at 1250?C for 8 h to obtaine dense ceramics. Dielectric constant, loss tangent and AC conductivity of the sintered Ce-doped SrBi2Nb2O9 and SrBi2Ta2O9 ceramics were measured by LCR meter. The Ce-doped SBN (SBCN) ceramics have a higher Curie temperature (TC) and dielectric constant at TC (380?C and ?? ~3510) compared to the Ce-doped SBT (SBCT) ceramics (330?C and ?? ~115) when measured at 100Hz. However, the Ce-doped SBT (SBCT) ceramics have lower conductivity and dielectric loss.


2021 ◽  
Vol 321 ◽  
pp. 23-27
Author(s):  
Simona Ravaszová ◽  
Karel Dvořák

The paper is focused on one of the most important component of Portland clinker-on the tricalcium silicate. The study reported in this article is focuses on the changes in crystallite size of synthetic tricalcium silicate obtained using solid state reaction method. Crystallite size changes are monitored during the grinding in three types of laboratory mills in two different conditions. Changing in crystallite size at various grinding time up to 120 minutes are studied with the aid of X-ray diffraction and using the Scherrer equation. It has been found that the most efficient laboratory mill in terms of speed and fineness of the material was the planetary mill.


2016 ◽  
Vol 34 (2) ◽  
pp. 437-445 ◽  
Author(s):  
Sumit K. Roy ◽  
S. Chaudhuri ◽  
R.K. Kotnala ◽  
D.K. Singh ◽  
B.P. Singh ◽  
...  

AbstractIn this work the X-ray diffraction, scanning electron microscopy, Raman and dielectric studies of lead free perovskite (1 – x)Ba0.06(Na1/2Bi1/2)0.94TiO3–xNaNbO3 (0 ⩽ x ⩽ 1.0) ceramics, prepared using a standard solid state reaction method, were investigated. X-ray diffraction studies of all the ceramics suggested the formation of single phase with crystal structure transforming from rhombohedral-tetragonal to orthorhombic symmetry with the increase in NaNbO3 content. Raman spectra also confirmed the formation of solid solution without any new phase. Dielectric studies showed that the phase transition is of diffusive character and diffusivity parameter decreases with increasing NaNbO3 content. The compositional fluctuation was considered to be the main cause of diffusivity.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Liu Zhirong ◽  
Zhang Huan ◽  
Wang Yun ◽  
Zhan Xinxing

Na-doped lithium metatitanate (Na-doped Li2TiO3) absorbent was doped with Na2CO3and lithium metatitanate (Li2TiO3) was prepared by a solid-state reaction method from mixture of TiO2and Li2CO3. The Na-doped lithium metatitanate was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) and surface area. Carbon dioxide absorption on Na-doped lithium metatitanate was investigated using TG-DTA. The results reveal an increase of the CO2absorption capacity of the Na-doped materials with respect to pure Li2TiO3. XRD patterns of the doped samples suggest a limited substitution of Li by Na atoms within the Li2TiO3structure. The results of experimental and modeling work were summarized to better understand the relationship between the sorbent microstructure and carbon dioxide absorption kinetics.


2020 ◽  
Vol 18 (11) ◽  
pp. 14-18
Author(s):  
Abbas K. Saadon ◽  
Kareem A. Jasim ◽  
Auday H. Shaban

The high temperature superconductor’s compounds are one of the hot spot field of science, due to their applications in industries. Hg0.8Sb0.2Ba2Ca2Cu3O8+δ and Hg0.8Sb0.2Ba2Ca1Cu2O6+δ, were manufactured using a doable-step of solid state reaction method. The samples were sintered at 800 ° C. The transition temperatures Tc are found from electrically resistively by using four probe techniques. The resistivity become zero when the transition temperature Tc(offset) have 131 and 119 K, and the onset temperature Tc(onset) have 139 K for Hg0.8Sb0.2Ba2Ca2Cu3O8+δ and 132 K for Hg0.8Sb0.2Ba2Ca1Cu2O6+δ. Analysis of X-ray diffraction showed a tetragonal structure with lattice parameters changes for all samples.


Sign in / Sign up

Export Citation Format

Share Document