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

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...

Changes in Crystallite Size of Tricalcium Silicate during the Laboratory Grinding

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.

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

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.

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

2016 ◽  
Vol 16 (4) ◽  
pp. 3684-3689 ◽  
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).

scholarly journals Synthesis of Vanadium (III) Doped Anatase TiO2 by Solid State Reaction Method

ALCHEMY ◽  
2018 ◽  
Vol 5 (1) ◽  
pp. 26
Author(s):  
Nur Aini ◽  
Rachamawati Ningsih
Keyword(s):  
Solid State ◽  
Visible Light ◽  
Solid State Reaction ◽  
Single Phase ◽  
Diffuse Reflectance Spectroscopy ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Vanadium Doping

Anatase of Titanium dioxide (TiO<sub>2</sub>)  was doped with vanadium ions (V<sup>3+</sup>), at doping levels ranging from 0.3, 0.5 to 0.7 atomic percentage in order to increase its photocatalytic activity under visible light irradiation. Vanadium doped TiO<sub>2</sub> was synthesized by solid state reaction method. Its physicochemical properties characterized by powder X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectroscopy (DRS). Doping with V(III) resulted in a single phase structure of anatase TiO<sub>2</sub> with nanosize crystal ranging from 53.06 to 59.59 nm. Vanadium doping also resulted in a red-shift of the photophysical response of TiO<sub>2</sub> that was reflected in an extended absorption in the visible light between 400 and 700 nm.

scholarly journals Study of the Structural, Magnetic and Transport properties of La3+ Doped Cu-Zn Ferrite

2020 ◽  
Vol 12 (3) ◽  
pp. 259-267
Author(s):  
K. Nahar ◽  
M. A. Hossain ◽  
P. Roy ◽  
M. N. I. Khan ◽  
S. S. Sikder
Keyword(s):  
Solid State ◽  
Diffraction Pattern ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
Reaction Method ◽  
X Ray ◽  
Zn Ferrite ◽  
La Doped

Crystalline La doped Cu-Zn ferrite with compositions Cu0.15Zn0.85LaxFe2-xO4 [ x = 0.00, 0.02, 0.04, 0.06 and 0.08] were synthesized by using conventional solid state reaction method technique. X-ray diffraction pattern (XRD), Crystalline La doped Cu-Zn ferrite with compositions Cu0.15Zn0.85LaxFe2-xO4 [x = 0.00, 0.02, 0.04, 0.06 and 0.08] were synthesized by using conventional solid state reaction method technique. X-ray diffraction pattern (XRD), scanning electron micrographs (SEM), hysteresis loop (M-H) curves and frequency dependent resistivity were employed to inspect the effect of La3+ doping on the structure, microstructure, magnetic and transport properties of the specimens. All the specimens exhibited fcc type cubic spinel structure where the particle size were within 500-1600 nm range. Magnetically ferromagnetic phenomenon was found for all the samples where the effect of La3+ doping consequence on the variation of various parameters like saturation magnetization (Ms), coercivity (Hc) and remanent magnetization (Mr). The resistivity tuned by frequency for all the samples presented the decreasing phenomenon with the increase of applied frequency.

scholarly journals Ferroelectric Transition in Sr- and W-Doped BaTiO3 Solid Solutions

2021 ◽  
Vol 11 (15) ◽  
pp. 6760
Author(s):  
Heeju Ahn ◽  
Eunjeong Lee ◽  
Yujin Cho ◽  
Dongyeon Bae ◽  
Hee Jung Park ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Curie Temperature ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Lattice Constants ◽  
A Value ◽  
Curie Temperature Tc

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.

Phase relations in the Ba–Sr–Co–Fe–O system at 1273 K in air

2009 ◽  
Vol 42 (2) ◽  
pp. 153-160 ◽  
Author(s):  
Zhèn Yáng ◽  
Ashley S. Harvey ◽  
Anna Infortuna ◽  
Ludwig J. Gauckler
Keyword(s):  
High Temperature ◽  
Solid State ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Solid State Reaction Method ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray

Selected compositions of the Ba–Sr–Co–Fe–O system were synthesized from powders by the solid-state reaction method. Samples were equilibrated at 1273 K for 36 000 s in air. The resulting powders were characterized by X-ray diffraction (XRD) at room temperature and by high-temperaturein situXRD. The phases present in the BaxSr1−xCoyFe1−yO3−δsystem are outlined for 1273 K in air. For most of the quaternary compositions, the cubic perovskite is formed, except for the compositions withx= 1 (excludingy= 0.4),y= 1 andx,y= 0.8, where the phases mainly show hexagonal distortions, andx, y= 0, for which a predominant cubic phase is mixed with other phases.

scholarly journals Effect of Zr addition on structure and electrical properties of SmFeO3 prepared by solid state reaction method

2017 ◽  
Vol 11 (4) ◽  
pp. 275-281 ◽  
Author(s):  
Abdalla Abdalla ◽  
Shahzad Hossain ◽  
Pg. Petra ◽  
Abul Azad
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Single Phase ◽  
Solid State Reaction Method ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Zr Addition ◽  
Pbnm Space Group

Series of Sm1-xFe1-3xZr3xO3 (SFZO, where x = 0.0, 0.01, 0.02, 0.033, 0.05, 0.1 and 0.15), was synthesised by the solid state reaction method and sintered at 1500?C in air. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate the structure of the materials. The XRD results indicated that the pure SmFeO3 and Sm0.99Fe0.97Zr0.03O3 samples are single phase materials with an orthorhombic symmetry and Pbnm space group. The increase of Zr content (x ? 0.02) causes a phase change from single to twophase system with orthorhombic (Pbnm) and fluorite symmetry (Fm?3m). The microstructural analyses showed that the Zr4+ doping resulted in an increase of porosity in the sintered SFZO compared to SmFeO3 sample. The direct current (DC) electrical conductivity at 850?C in air was found to be 0.045 S/cm and 0.007 S/cm for Sm0.99Fe0.97Zr0.03O3 and SmFeO3, respectively, showing a significant enhancement compared to the pure SmFeO3.

Structural and Luminescence Properties of Eu3+ and Dy3+-Doped Magnesium Boro-Tellurite Ceramics

2014 ◽  
Vol 895 ◽  
pp. 269-273
Author(s):  
Nur Zu Ira Bohari ◽  
Rosli Hussin ◽  
Zuhairi Ibrahim ◽  
M.H. Haji Jumali ◽  
Royston Uning ◽  
...  
Keyword(s):  
Solid State ◽  
Ftir Spectroscopy ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Luminescence Properties ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Xrd Studies ◽  
The Eu

Boro-tellurite ceramics with the composition of 60B2O3-10TeO2-30MgO-1Eu2O3-1Dy2O3 in mol % were prepared by solid-state reaction method. The samples were characterized by x-ray diffraction (XRD), photoluminescence (PL) and FTIR spectroscopy. The XRD studies have revealed the presence of MgTe2O5 and MgB6O10.7H2O crystalline as the major and minor phases in these samples. The FTIR spectra reveal the presence of B-O vibrations of B-O-B, BO3 and BO4 bridging oxygen and Te-O stretching modes of Te2O, TeO3 and TeO4 units in the prepared ceramics. The PL peaks were assigned to the Eu3+ transitions 5D07F0 at 580 nm, 5D07F1 at 591 nm and 596 nm, 5D07F2 at 612, 618 and 621 nm, 5D07F3 at 651 nm, and 5D07F4 at 692 nm and 702 nm when excited at 394 nm.

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