Enhanced photoluminescence of SrWO4:Eu3+ red phosphor synthesized by mechanochemically assisted solid state metathesis reaction method at room temperature

2015 ◽  
Author(s):  
Anthuvan John Peter ◽  
I. B. Shameem Banu
2010 ◽  
Vol 160-162 ◽  
pp. 594-598
Author(s):  
Guo Jian Jiang ◽  
Jia Yue Xu ◽  
Hui Shen ◽  
Yan Zhang ◽  
Lin He Xu ◽  
...  

Zinc silicate-based (Zn2SiO4:Eu3+) long afterglow phosphors were produced by solid state reaction method. The effects of borax and Eu2O3 additive on the properties of fabricated products have been studied. The results show that, there is not much difference in phase compositions within the borax additive amount; however, their SEM morphologies are different. Borax additive can increase the grain size of the product. Some sintering phenomena could be observed in the sample with Eu2O3 addition. The fluorescence spectroscopy results indicate that, the emission peak of the sample with Eu3+ additive located at 612nm, which may be a good candidate for red phosphor applications. The luminescent mechanism of Zn2SiO4:Eu3+ is also discussed.


2021 ◽  
Author(s):  
Hang Yu ◽  
Wenwen Bu ◽  
Zijia Wang ◽  
Zhuoyue Zhao ◽  
Mehwish Jadoon ◽  
...  

Polyoxometalate nanoparticles were synthesized via a concise solid-state reaction method by directly grinding silver nitrate and the polyoxometalate (NH4)5H6PMo4V8O40 at room temperature without the assistance of a surfactant.


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.


2011 ◽  
Vol 497 ◽  
pp. 31-37 ◽  
Author(s):  
Toru Kyomen ◽  
Ryuta Motani ◽  
Minoru Hanaya

Powder of Pr-doped CaTiO3 red phosphor was prepared at 1473 K by a conventional solid-state reaction method with addition of B2O3 or SiO2 as a flux. Primary particle sizes of the prepared samples were increased by using B2O3 flux but decreased by using SiO2 flux. Clear planes, edges, or steps were observed on surfaces of the primary particles. The intensity of photoluminescence induced by irradiation of light with a wavelength longer than ∼350 nm was enhanced about three times by using B2O3 flux. The intensity of photoluminescence induced by irradiation of light with a wavelength shorter than ∼350 nm was enhanced about twice by using either B2O3 or SiO2 fluxes. The origin for the flux effects is discussed.


2017 ◽  
Vol 126 (1B) ◽  
pp. 147
Author(s):  
Nguyen Thi Thuy

<p><strong>Abstract: </strong>LaFeO<sub>3</sub> system with doped Ti, Co, Cu was manufactured by solid state reaction method, it was sintered at 1250<sup>0</sup>C and 1290<sup>0</sup>C in 10 hours with a heating rate of 3<sup>0</sup>C/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<sup>+3</sup>. 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(Fe<sub>0,2</sub>Co<sub>0,2</sub>Ti<sub>0,6</sub>)O<sub>3</sub> and La(Fe<sub>0,4</sub>Cu<sub>0,1</sub>Ti<sub>0,5</sub>)O<sub>3 </sub>, 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 900<sup>0</sup>C, Seebeck coefficient S of La(Fe<sub>0.6</sub>Ti<sub>0.4</sub>)O<sub>3</sub> can be change from positive to negative at the temperature of around 700<sup>0</sup>C.</p>


2006 ◽  
Vol 29 (2) ◽  
pp. 115-118 ◽  
Author(s):  
Purnendu Parhi ◽  
Satya Sadhan Singh ◽  
Alok R. Ray ◽  
A. Ramanan

2016 ◽  
Vol 848 ◽  
pp. 222-227 ◽  
Author(s):  
Zi Jun Song ◽  
Lian Jun Wang ◽  
Wan Jiang ◽  
Wei Luo

Oxide ceramic is a kind of environmental friendly materials, which has attracted more and more interests for its bunch of advantages such as sound chemical, thermal stability, simple synthetic process, cheap price, harmless and safety. Therefore, Oxide ceramic will be a promising material in the future. In this work, polycrystalline samples of CuAlO2 were prepared by a solid state reaction method. The mixture of pure CuO and Al2O3 powders was firstly pressed under the pressure of 60 MPa, and then 200 MPa to prepare pellets of 5 mm thick and 10 mm in diameter. The green compacts were sintered at five different temperatures (1273 K, 1323 K, 1373 K, 1423 K, 1473 K) for various holding times (5 h, 10 h and 15 h) in the air and then the furnace cooled. The crystalline and microstructures of the sintered CuAlO2 bodies were detected by XRD and SEM. The properties of density, thermal conductivity were also investigated in detail. The experimental results show that CuAlO2 bodies were rhombohedral, belonging to R3m space group. It is found that the density and the thermal conductivity of CuAlO2 ceramics were significantly dependent on the sintering temperatures. The density and thermal conductivity increased with increasing the sintering temperatures. The thermal conductivity of samples sintered at 1273 and 1473 K with the same holding time (10 h) were 9.70 and 35.53 W/mk at the room temperature, 3.41 and 8.29 W/mk at 1100 K, respectively.


2018 ◽  
Vol 6 (3) ◽  
pp. 491-499 ◽  
Author(s):  
Mengmeng Zhu ◽  
Yuexiao Pan ◽  
Yaqi Huang ◽  
Hongzhou Lian ◽  
Jun Lin

A novel red phosphor Li3Na3Ga2F12:Mn4+was obtained at room temperature and its luminescence efficiency has been improved by optimizing the synthetic process.


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