STUDY OF SELENIUM DOPED Bi-BASED SUPERCONDUCTORS BY AES AND SEM

Compositions in Bi 2 Sr 2 Ca 2 Cu 3 O y: Se x with x = 0, 0.05, 0.1, 0.2, 0.3, 0.4 have been prepared by the solid state reaction method. The samples have initially been studied by the X-ray powder diffraction method for structural characterization. Superconducting transition temperatures (T c ) measured by the four probe technique shows dependence on selenium concentration. A detailed microstructural analysis has been carried out by scanning electron and Auger electron spectroscopies in order to investigate the incorporation of selenium in the grains of the superconductors. It is found that Se concentration affects both the T c values and the morphology of the grains. AES studies clearly show the presence of selenium in the grains of the superconductor.

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Thermoelectric properties of LaFeO3 system with doped Ti, Co, Cu

HUE UNIVERSITY JOURNAL OF SCIENCE NATURAL SCIENCE ◽

10.26459/hueuni-jns.v126i1b.4155 ◽

2017 ◽

Vol 126 (1B) ◽

pp. 147

Author(s):

Nguyen Thi Thuy

Keyword(s):

Electron Microscope ◽

Solid State ◽

Room Temperature ◽

Unit Cell Volume ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Scanning Electron

Abstract: LaFeO3 system with doped Ti, Co, Cu was manufactured by solid state reaction method, it was sintered at 12500C and 12900C in 10 hours with a heating rate of 30C/min. Using X-ray diffraction and Scanning Electron Microscope (SEM) to examine the structure, it reveals that samples are single-phase and orthogonal-perovskite structure describing by the Pnma space group, the unit cell volume of the samples increases when Ti, Co, Cu are doped to replace ion Fe+3. The size of particle increase while raising the temperature of sintering. Measuring the resistance which depends on temperature between the room temperature and 1000K, it can be seen that when doping Co, Cu with the nominal component La(Fe0,2Co0,2Ti0,6)O3 and La(Fe0,4Cu0,1Ti0,5)O3 , the conductivity of samples increases respectively. Especially, the conductivity of Cu doped sample is higher than two other samples, and reach the highest conductivity at about 9000C, Seebeck coefficient S of La(Fe0.6Ti0.4)O3 can be change from positive to negative at the temperature of around 7000C.

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Synthesis of Nb2AlC Material by High Temperature Solid State Reaction Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.655.240 ◽

2015 ◽

Vol 655 ◽

pp. 240-243 ◽

Cited By ~ 2

Author(s):

Yu Chen Wang ◽

Zhen Hua Liang ◽

Gui Hua Peng ◽

Jian Guang Xu

Keyword(s):

High Temperature ◽

Solid State ◽

Solid State Reaction ◽

Raw Materials ◽

Heating Temperature ◽

Solid State Reaction Method ◽

Atomic Ratio ◽

Reaction Method ◽

X Ray ◽

Scanning Electron

The Nb2AlC powders were synthesized by high temperature solid state reaction method ,in which, the mixed powders of niobium (Nb), aluminum (Al) , graphite (C) were used as raw materials in an atomic ratio of 2.0:1.1:1.0, respectively. And the heating temperature was adjusted in a range of 1600–1650°C in order to investigate the effects of different preparing conditions on the synthesis of Nb2AlC .The phase composition and morphology of the products were analyzed by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) respectively. The results indicated that all the XRD peaks can be indexed as Nb2AlC with improved crystallization at 1610°C.And the SEM photographs show that the products are layered morphology.The reaction mechanism of Nb2AlC synthesis was also studied.

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Investigations of M3Al8O15:Eu3+,Dy3+ (M = Ba, Ca, Mg) phosphors

Materials Science-Poland ◽

10.1515/msp-2016-0047 ◽

2016 ◽

Vol 34 (2) ◽

pp. 412-417

Author(s):

Esra Öztürk

Keyword(s):

Electron Microscopy ◽

Solid State Reaction Method ◽

Morphological Characterization ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Three Samples ◽

Scanning Electron ◽

The Eu

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.

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Pengaruh Suhu Sintering Terhadap Sintesis Silicon Carbide (SiC) Berbahan Dasar Abu Sekam Padi dan Grafit Pensil 2B

INDONESIAN JOURNAL OF APPLIED PHYSICS ◽

10.13057/ijap.v5i01.258 ◽

2015 ◽

Vol 5 (01) ◽

pp. 31

Author(s):

Resky Irfanita ◽

Asnaeni Ansar ◽

Ayu Hardianti Pratiwi ◽

Jasruddin J ◽

Subaer S

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Silicon Carbide ◽

Rice Husk Ash ◽

Sintering Temperature ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Scanning Electron

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

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Structure and electric properties of cerium substituted SrBi1.8Ce0.2Nb2O9 and SrBi1.8Ce0.2Ta2O9 ceramics

Processing and Application of Ceramics ◽

10.2298/pac1603183a ◽

2016 ◽

Vol 10 (3) ◽

pp. 183-188 ◽

Cited By ~ 5

Author(s):

Mohamed Afqir ◽

Amina Tachafine ◽

Didier Fasquelle ◽

Mohamed Elaatmani ◽

Jean-Claude Carru ◽

...

Keyword(s):

Dielectric Constant ◽

Solid State ◽

Room Temperature ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Lcr Meter ◽

Curie Temperature Tc

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.

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Thermal enhancement of 2H11/2→4I15/2 up-conversion luminescence of Er3+ doped K2Yb(PO4)(MoO4) phosphors

Journal of Materials Chemistry C ◽

10.1039/d1tc02442f ◽

2021 ◽

Author(s):

Hongqiang Cui ◽

Yongze Cao ◽

Lei Zhang ◽

Yuhang Zhang ◽

Siying Ran ◽

...

Keyword(s):

Crystal Structure ◽

Solid State ◽

Solid State Reaction ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Orthorhombic Crystal ◽

Orthorhombic Crystal Structure ◽

Reaction Method ◽

X Ray ◽

Thermal Enhancement

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...

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Changes in Crystallite Size of Tricalcium Silicate during the Laboratory Grinding

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.321.23 ◽

2021 ◽

Vol 321 ◽

pp. 23-27

Author(s):

Simona Ravaszová ◽

Karel Dvořák

Keyword(s):

Solid State ◽

Crystallite Size ◽

Solid State Reaction ◽

Solid State Reaction Method ◽

Tricalcium Silicate ◽

Planetary Mill ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Grinding Time

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.

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Superconducting Compound Hg0.8Sb0.2Ba2Ca2Cu3O8+δ Compared with Hg0.8Sb0.2Ba2Ca1Cu2O6+δ to Evaluate Transition Temperature

NeuroQuantology ◽

10.14704/nq.2020.18.11.nq20229 ◽

2020 ◽

Vol 18 (11) ◽

pp. 14-18

Author(s):

Abbas K. Saadon ◽

Kareem A. Jasim ◽

Auday H. Shaban

Keyword(s):

High Temperature ◽

Transition Temperature ◽

Solid State ◽

Solid State Reaction ◽

Hot Spot ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Superconducting Compound

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.

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Luminescence Properties of Self-Activated M3(VO4)2 (M = Mg, Ca, Sr, and Ba) Phosphors Synthesized by Solid-State Reaction Method

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11825 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3684-3689 ◽

Cited By ~ 11

Author(s):

Xin Min ◽

Zhaohui Huang ◽

Minghao Fang ◽

Yan’gai Liu ◽

Chao Tang ◽

...

Keyword(s):

Solid State ◽

Solid State Reaction ◽

Single Phase ◽

Uv Light ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Light Emitting ◽

Reaction Method ◽

X Ray ◽

Yield Decrease

In this paper, M3(VO4)2 (M = Mg, Ca, Sr, and Ba) self-activated phosphors were prepared by a solid-state reaction method at 1,000 °C for 5 h. The phase formation and micrographs were analyzed by X-ray diffraction and scanning electron microscopy. The Ca3(VO4)2 phosphor does not show any emission peaks under excitation with ultraviolet (UV) light. However, the M3(VO4)2 (M = Mg, Sr, and Ba) samples are effectively excited by UV light chips ranging from 200 nm to 400 nm and exhibit broad emission bands due to the charge transfer from the oxygen 2p orbital to the vacant 3d orbital of the vanadium in the VO4. The color of these phosphors changes from yellow to light blue via blue-green with increasing ionic radius from Mg to Sr to Ba. The luminescence lifetimes and quantum yield decrease with the increasing unit cell volume and V–V distance, in the order of Mg3(VO4)2 to Sr3(VO4)2 to Ba3(VO4)2. The emission intensity decreases with the increase of temperatures, but presents no color shift. This confirms that these self-activated M3(VO4)2 phosphors can be suggested as candidates of the single-phase phosphors for light using UV light emitting diodes (LEDs).

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Blue Upconversion Luminescence from Phosphor Tm3+/Yb3+ Co-Doped Gd2Mo3O9

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.683.3 ◽

2013 ◽

Vol 683 ◽

pp. 3-6

Author(s):

Jia Yue Sun ◽

Bing Xue ◽

Guang Chao Sun ◽

Dian Peng Cui ◽

Hai Yan Du

Keyword(s):

Solid State ◽

Upconversion Luminescence ◽

Blue Emission ◽

Solid State Reaction Method ◽

Solid State Lighting ◽

Red Emission ◽

Reaction Method ◽

X Ray ◽

Strong Blue Emission ◽

Co Doped

The upconversion (UC) luminescence properties of phosphor Tm3+/Yb3+co-doped Gd2Mo3O9were investigated in detail. Tm3+/Yb3+co-doped Gd2Mo3O9was prepared by solid-state reaction method using Na2CO3as flux and characterized by powder X-ray diffractometry. Under 980nm excitation, Tm3+/Yb3+co-doped Gd2Mo3O9has exhibited a weak red emission near 651nm and strong blue emission at 476nm. Tm3+/Yb3+co-doped Gd2Mo3O9phosphor has been considered as a better candidate in solid-state lighting applications.

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