scholarly journals Synthesis and Characterization of a Novel Sm+3 Activated NaCdVO4 Phosphors for Red Emitting Material

2021 ◽  
Author(s):  
Marwa Enneffati ◽  
Mohammed Rasheed ◽  
Narjes Aouani ◽  
Bassem Louati ◽  
Kamel Guidara ◽  
...  
Keyword(s):  
Solid State Reaction Method ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
White Leds ◽  
Chromaticity Coordinates ◽  
Cie Chromaticity ◽  
Simple Solid State Reaction ◽  
Reflectance Data

Abstract Sm3+ activated NaCdVO4 phosphors were prepared by the simple solid-state reaction method. X-ray diffraction, dispersive energy (EDS), scanning electron microscope (SEM), infrared as well as photoluminescence (PL) techniques were used to characterize obtained samples. Irregular and non-uniform structures were observed by SEM. EDS spectra confirmed the presence of Na, Cd, V, O and Sm elements in each sample. Uuder 405nm excitation, the NaCd1 − xVO4: xSm (x = 0.01, 0.03 and 0.05) exhibits a bright red emission consisting mainly of four wavelength peaks at 556, 593, 650 and 700 nm. The highest emission intensity was found with a composition of x = 0.05. The analysis of PL spectra suggest that studied samples can be used as a red emitting phosphors candidates for fabrication of white LEDs. The CIE chromaticity coordinates of prepared samples were close to the blue-emitting phosphors for NaCdVO4 and red-emitting ones for NaCd0.99Sm0.01VO4, NaCd0.97Sm0.03VO4, and NaCd0.95Sm0.05VO4. The band gap energies of phosphors were calculated from reflectance data using K-M function.

Synthesis and Characterization of Low Density Bi-2223 Cuprates Superconductor Doped Eu2O3 Nanoparticles

2021 ◽  
Vol 317 ◽  
pp. 131-137
Author(s):  
Suhaimi Nurbaisyatul Ermiza ◽  
Azhan Hashim ◽  
Azman Kasim ◽  
Norazila Ibrahim ◽  
Siti Fatimah Saipuddin
Keyword(s):  
Solid State Reaction Method ◽  
Synthesis And Characterization ◽  
Crystallographic Structure ◽  
Low Density ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Resistivity Measurements

Bi1.6Pb0.4Sr2Ca2-xEuxCu3Oδ cuprates superconductor doped with Eu nanoparticles (x = 0.0000, 0.0025, 0.0200 and 0.0500) were synthesized through conventional solid state reaction method. Crystalline sucrose was added during pelletization and burn at 400°C for two hours to create low density sample. The effect of doping Eu2O3 nanoparticles on the structural and superconducting properties by means of critical temperature (Tc), critical current density (Jc), X-ray diffraction (XRD) together with Field Emission Scanning Electron Microscopy (FESEM) and Alternating Current Susceptibility (ACS) were studied. Based on XRD analyses, the crystallographic structure has shown slightly changed from tetragonal to orthorhombic. The amount of 2223 phase gradually decreased with the increment of Eu concentration which indicates that Eu nanoparticles substitution favours the growth of 2212 phases. The resistivity measurements show that the highest Tcvalue for doped samples found at 90 K for x = 0.0025. The FESEM images showed that the plate-like grains become smaller and distributed randomly without specific alignment due to the increment of Eu concentration.

Synthesis and Characterization of YAG:Ce Phosphor by Microwave Induced Combustion Synthesis with Different Fuel Sources

2020 ◽  
Vol 301 ◽  
pp. 69-76
Author(s):  
Khai Shenn Lau ◽  
Zainuriah Hassan ◽  
Way Foong Lim ◽  
Hock Jin Quah ◽  
Naser Mahmoud Ahmed ◽  
...  
Keyword(s):  
Combustion Synthesis ◽  
Luminescent Properties ◽  
Yttrium Aluminium Garnet ◽  
X Ray Diffraction ◽  
Mixed Fuel ◽  
X Ray ◽  
White Leds ◽  
Yttrium Aluminium ◽  
Cie Chromaticity

White LEDs (WLEDs) have been produced from the combination of blue LED chips and phosphor converter. In the present work, considerable amount of yttrium aluminium garnet (YAG) phosphor powders doped with 0.3 mol% of cerium (Ce) have been synthesized via Microwave Induced Combustion Synthesis (MICS) method with different fuel sources such as urea and mixed fuel of urea and glycine. The effects of different fuel sources on the crystallinity, structure, luminescent properties and Commision International de L’Eclairage (CIE) chromaticity was characterized and studied using high resolution X-ray diffraction (HR XRD), field emission-scanning electron microscopy (FE SEM), energy dispersive X-ray spectroscopy (EDX), electroluminescence (EL) and standard CIE 1931 chromaticity diagram, respectively. The highest EL intensity can be observed from the sample prepared by mixed fuel technique. In contrast, the experimental enhancement in the aforementioned properties was demonstrated by the WLED synthesized using mixed fuel technique. Keywords: White LEDs, phosphor converter, microwave induced combustion, mixed fuel technique.

Synthesis and characterization of TiN / Ti / AISI 410 coatings

2018 ◽  
Vol 2 (1) ◽  
pp. 7
Author(s):  
S Chirino ◽  
Jaime Diaz ◽  
N Monteblanco ◽  
E Valderrama
Keyword(s):  
Synthesis And Characterization ◽  
Photoemission Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Columnar Grains ◽  
Tin Thin Films ◽  
Steel Aisi ◽  
Interacting Surfaces ◽  
Stainless Steel Aisi

The synthesis and characterization of Ti and TiN thin films of different thicknesses was carried out on a martensitic stainless steel AISI 410 substrate used for tool manufacturing. The mechanical parameters between the interacting surfaces such as thickness, adhesion and hardness were measured. By means of the scanning electron microscope (SEM) the superficial morphology of the Ti/TiN interface was observed, finding that the growth was of columnar grains and by means of EDAX the existence of titanium was verified.  Using X-ray diffraction (XRD) it was possible to observe the presence of residual stresses (~ -3.1 GPa) due to the different crystalline phases in the coating. Under X-ray photoemission spectroscopy (XPS) it was possible to observe the molecular chemical composition of the coating surface, being Ti-N, Ti-N-O and Ti-O the predominant ones.

scholarly journals Synthesis and Characterization of Clay Polymer Nanocomposites of P(4VP-co-AAm) and Their Application for the Removal of Atrazine

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 721 ◽  
Author(s):  
Jorge A. Ramírez-Gómez ◽  
Javier Illescas ◽  
María del Carmen Díaz-Nava ◽  
Claudia Muro-Urista ◽  
Sonia Martínez-Gallegos ◽  
...  
Keyword(s):  
Polymer Nanocomposites ◽  
Nanocomposite Materials ◽  
Synthesis And Characterization ◽  
Cross Linking ◽  
X Ray Diffraction ◽  
Numerous Species ◽  
X Ray ◽  
Different Types ◽  
Synthesized Materials

Atrazine (ATZ) is an herbicide which is applied to the soil, and its mechanism of action involves the inhibition of photosynthesis. One of its main functions is to control the appearance of weeds in crops, primarily in corn, sorghum, sugar cane, and wheat; however, it is very toxic for numerous species, including humans. Therefore, this work deals with the adsorption of ATZ from aqueous solutions using nanocomposite materials, synthesized with two different types of organo-modified clays. Those were obtained by the free radical polymerization of 4-vinylpyridine (4VP) and acrylamide (AAm) in different stoichiometric ratios, using tetrabutylphosphonium persulfate (TBPPS) as a radical initiator and N,N′-methylenebisacrylamide (BIS) as cross-linking agent. The structural, morphological, and textural characteristics of clays, copolymers, and nanocomposites were determined through different analytical and instrumental techniques, i.e., X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Adsorption kinetics experiments of ATZ were determined with the modified and synthesized materials, and the effect of the ratio between 4VP and AAm moieties on the removal capacities of the obtained nanocomposites was evaluated. Finally, from these sets of experiments, it was demonstrated that the synthesized nanocomposites with higher molar fractions of 4VP obtained the highest removal percentages of ATZ.

scholarly journals High-pressure synthesis and characterization of the non-centrosymmetric scandium borate ScB6O9(OH)3

2020 ◽  
Vol 75 (6-7) ◽  
pp. 597-603
Author(s):  
Birgit Fuchs ◽  
Hubert Huppertz
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Structure Solution ◽  
Temperature Experiment ◽  
Pressure Synthesis

AbstractThe non-centrosymmetric scandium borate ScB6O9(OH)3 was obtained through a high-pressure/high-temperature experiment at 6 GPa and 1473 K. Single-crystal X-ray diffraction revealed that the structure is isotypic to InB6O9(OH)3 containing borate triple layers separated by scandium layers. The compound crystallizes in the space group Fdd2 with the lattice parameters a = 38.935(4), b = 4.4136(4), and c = 7.6342(6) Å. Powder X-ray diffraction and vibrational spectroscopy were used to further characterize the compound and verify the proposed structure solution.

One Step Synthesis and Characterization of Zirconia-Graphene Composites

2012 ◽  
Vol 600 ◽  
pp. 174-177 ◽  
Author(s):  
Jian Fei Xia ◽  
Zong Hua Wang ◽  
Yan Zhi Xia ◽  
Fei Fei Zhang ◽  
Fu Qiang Zhu ◽  
...  
Keyword(s):  
Synthesis And Characterization ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Graphene Composite ◽  
Transmission Electron ◽  
One Step ◽  
Ft Ir ◽  
Xrd Techniques

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.

Synthesis and Characterization of Multiferroic NiFe2O4/BiFeO3 Nanocomposites by Modified Pechini Method

2011 ◽  
Vol 197-198 ◽  
pp. 456-459
Author(s):  
Xian Ming Liu ◽  
Wen Liang Gao
Keyword(s):  
Pechini Method ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Magnetic Bias ◽  
Field Frequency ◽  
Magnetic Field Frequency ◽  
X Ray ◽  
Structure And Morphology ◽  
Modified Pechini Method

Spinel-perovskite multiferroics of NiFe2O4/BiFeO3 nanoparticles were prepared by modified Pechini method. The structure and morphology of the composites were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the composites consisted of spinel NiFe2O4 and perovskite BiFeO3 after annealed at 700°C for 2h, and the particle size ranges from 40 to 100nm. VSM and ME results indicated that the nanocomposites exhibited both tuning magnetic properties and a ME effect. The ME effect of the nanocomposites strongly depended on the magnetic bias and magnetic field frequency.

Hydrothermal Synthesis and Characterization of BiFeO3 Polyhedral Crystallites

2012 ◽  
Vol 174-177 ◽  
pp. 508-511
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang ◽  
Xiao Feng Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.

Synthesis and Characterization of a Fluorescent Dianthraceno­indacene

Synlett ◽  
2018 ◽  
Vol 29 (19) ◽  
pp. 2562-2566 ◽  
Author(s):  
Michael Haley ◽  
Conerd Frederickson ◽  
Joshua Barker ◽  
Justin Dressler ◽  
Zheng Zhou ◽  
...  
Keyword(s):  
Neutral Molecule ◽  
Conical Intersection ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Irreversible Reduction ◽  
Inside Out

A freely soluble dianthracenoindacene derivative has been synthesized using an ‘inside-out’ Friedel–Crafts alkylation method and is the first fluorescent diacenoindacene reported. Linear fusion of the anthracenes is confirmed by X-ray diffraction studies on the neutral molecule as well as its dianion. Based on predictions from our previous studies, this is also the least antiaromatic diacenoindacene derivative yet to be prepared, which is reflected in its highly negative and irreversible reduction. With its paratropicity essentially eliminated, we posit that the molecule is no longer deactivated by a conical intersection, typical of antiaromatic molecules, and therefore fluorescence is restored. This follows the trend shown in the related dianthracenopentalenes, with the reappearance of fluorescence when the outer acene groups are extended to linearly-fused anthracene moieties.

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

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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