scholarly journals Synthesis And Structural Characterization of Samarium Doped Silica Nanopowder

2021 ◽  
Vol 16 (2) ◽  
Author(s):  
Neelam Rani ◽  
Rachna Ahlawat ◽  
Surender Ahlawat
Keyword(s):  
Sol Gel ◽  
Research Work ◽  
Cubic Phase ◽  
Average Crystalline Size ◽  
X Ray Diffraction ◽  
Structural Morphology ◽  
Structure Information ◽  
Sem Study ◽  
Sol Gel Process ◽  
Silica Nanopowder

In the current research work, we demonstrate the synthesis of Samarium doped silica nanopowder through wetchemical technique. The phenomenon correlated to structural morphology is proposed and conferred. Nanocrystalline form of Sm-SiO2 powder has been formulated via sol-gel process. Performance of this method is absolutely correct for massive production and it is also a profitable in the sense of money. The ready sample are treated thermally at temperature 900ºC which are characterized through different supportive instrumental techniques as like ‘X-Ray Diffraction’ (XRD), ‘Fourier Transform Infrared Spectroscopy’ (FTIR) and ‘Scanning Electron Microscope’ (SEM) with EDX etc. The cubic phase of prepared sample is confirmed by XRD with average crystalline size ~18 nm using well known Debye-Scherer's formula and lattice constant is calculated as 10.8 Å. The surface morphology and microparticles structure information are collected from the SEM study. Investigation proposed that different nanoscopic collaborations play a key role in defining the morphology and crystal phase of ready materials. Presently, activity in this area is concentrated on the synthesis of glowing material via advanced methods and inspecting standard utilization in the area of microchips, photonics, flashes, sensors, optical intensification and fluorescent detecting appliances.

Luminescence properties of R2MoO6:Eu3+ (R = Gd, Y, La) phosphors prepared by Pechini sol-gel process

2005 ◽  
Vol 20 (10) ◽  
pp. 2676-2681 ◽  
Author(s):  
Maolin Pang ◽  
Xiaoming Liu ◽  
Jun Lin
Keyword(s):  
Grain Size ◽  
Sol Gel ◽  
Luminescent Properties ◽  
Luminescence Properties ◽  
X Ray Diffraction ◽  
Powder Morphology ◽  
X Ray ◽  
Average Grain Size ◽  
Sem Study ◽  
Sol Gel Process

R2MoO6:Eu3+ (R = Gd, Y, La) phosphors were prepared by the Pechini sol-gel process. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), reflectance spectra, photoluminescence (PL) spectra, and lifetimes were used to characterize the resulting phosphors. The results of XRD indicate that all of the R1.96Eu0.04MoO6 (R = Gd, Y, La) phosphors crystallized completely at 800 °C. Y1.96Eu0.04MoO6 and Gd1.96Eu0.04MoO6 are of isomorphous monoclinic (α) structure, while La1.96Eu0.04MoO6 preferentially adopts the tetragonal (γ) form. FE-SEM study reveals that the samples mainly consist of aggregated particles with an average grain size ranging from 100 to 250 nm. The luminescent properties of R2MoO6:Eu3+ (R = Gd, Y, La) phosphors are largely dependent on their structure, grain size, and powder morphology. The isomorphous Y2MoO6:Eu3+ and Gd2MoO6:Eu3+ phosphors show very similar luminescence properties, which differ greatly from that of the La2MoO6:Eu3+ phosphor.

scholarly journals Effect of Na Content on the Physical Properties ofBa0.5Sr0.5TiO3Powders

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Tassanee Tubchareon ◽  
Soipatta Soisuwan ◽  
Somchai Ratanathammaphan ◽  
Piyasan Praserthdam
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxygen Deficiency ◽  
Sol Gel ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Paramagnetic Resonance ◽  
Vacancy Defects ◽  
X Ray ◽  
Sol Gel Process ◽  
A Site

The different Na contents (0 ≤ Na ≤ 0.35, based on mole of NaOH) of doped Ba0.5Sr0.5TiO3(BST) powders synthesized via sol-gel process were studied. The substitution of Na+ions into a partial A-site of BST powders provided the reduction in vacancy defects as confirmed by electron paramagnetic resonance (EPR) and UV-visible spectroscopy. Photoluminescence (PL) spectra appeared in violet, blue, and green emissions. The phase structure, oxygen deficiency, and titanium deficiency of BST powders were further investigated as a function of Na content. X-ray diffraction (XRD) result was found that low Na content (0 ≤ Na ≤ 0.15) exhibited the tetragonal structure, while it was transformed to the cubic phase when high Na content. Moreover, X-ray photoelectron spectroscopy (XPS) result revealed that the partial oxidation of Ti3+ions to Ti4+ions was observed at Na content lower than 0.05 mole, while more addition of Na content resulted in the increasing of the oxygen and the titanium deficiency. Furthermore, the result indicated the oxygen deficiency significantly formed at the A-site of Sr atoms more than that of Ba atoms.

scholarly journals Synthesis and characterization of nanocrystalline barium strontium titanate powder by a modified sol-gel processing

2016 ◽  
Vol 34 (1) ◽  
pp. 63-68 ◽  
Author(s):  
M.E. Azim Araghi ◽  
N. Shaban ◽  
M. Bahar
Keyword(s):  
Sol Gel ◽  
Research Work ◽  
Titanium Isopropoxide ◽  
Barium Acetate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Process ◽  
Crystallite Sizes ◽  
Ft Ir ◽  
Strontium Acetate

AbstractIn this research work, nanocrystalline BST (Ba0.6Sr0.4TiO3) powders were synthesized through a modified sol-gel process, using barium acetate, strontium acetate and titanium isopropoxide as the precursors. In this process, stoichiometric proportions of barium acetate and strontium acetate were dissolved in acetic acid and titanium (IV) isopropoxide was added to form BST gel. The as-formed gel was dried at 200 °C and then calcined in the temperature range of 600 to 850 °C for crystallization. The samples were characterized by infrared spectroscopy method (FT-IR), X-ray diffraction technique (XRD) and field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectroscopy. EDS analysis of these samples confirmed the formation of the final phase with the special stoichiometry. The formation of a cubic perovskite crystalline phase with nanoscale dimension was detected using the mentioned techniques. The results showed that the obtained crystallite sizes were 33 and 37 nm for BST powder calcined at 750 and 850 °C, respectively.

Luminescent Properties of Zn2SiO4:Eu3+,Dy3+ Phosphors via Sol-Gel Process

2012 ◽  
Vol 217-219 ◽  
pp. 733-736
Author(s):  
Xiu Mei Han ◽  
Shu Ai Hao ◽  
Ying Ling Wang ◽  
Gui Fang Sun ◽  
Xi Wei Qi
Keyword(s):  
Thermal Analysis ◽  
Ir Spectra ◽  
Sol Gel ◽  
Luminescent Properties ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Process ◽  
Ft Ir

Zn2SiO4:Eu3+, Dy3+ phosphors have been prepared through the sol-gel process. X-ray diffraction (XRD), thermogravimetric and ddifferential thermal analysis (TG-DTA), FT-IR spectra and photoluminescence spectra were used to characterize the resulting phosphors. The results of XRD indicated that the phosphors crystallized completely at 1000oC. In Zn2SiO4:Eu3+,Dy3+ phosphors, the Eu3+ and Dy3+ show their characteristic red(613nm, 5D0-7F2), blue (481nm, 4F9/2–6H15/2) and yellow (577nm, 4F9/2–6H13/2) emissions.

The Preparation and Photocatalytic Activity of SWNTs Doped ZnO/TiO2 Compound Films

2010 ◽  
Vol 97-101 ◽  
pp. 1611-1615 ◽  
Author(s):  
Qing Wang ◽  
Xin Li Li ◽  
Wei Nie ◽  
Yong Mei Xia ◽  
Jian Feng Dai
Keyword(s):  
Photocatalytic Activity ◽  
Absorption Spectra ◽  
Sol Gel ◽  
Composite Films ◽  
Wavelength Region ◽  
Tio2 Films ◽  
X Ray Diffraction ◽  
Sol Gel Process ◽  
Doped Zno ◽  
Walled Carbon Nanotubes

The ZnO/TiO2 composite films were deposited over glass using spin coating technique by sol-gel process. Single-walled carbon nanotubes (SWNTs) were used to modify the ZnO/TiO2 films successfully in this paper. The structure and composition of the ZnO/TiO2 composite and SWNTs doped ZnO/TiO2 composite were characterized by X-ray diffraction (XRD). The morphology of samples was characterized by scanning electron microscopy (SEM). The photocatalytic activity was investigated by photocatalytic degradation of aqueous methyl orange under ultraviolet (UV) radiation. The UV-vis absorption spectra of the ZnO/TiO2 films and SWNTs doped ZnO/TiO2 films in the wavelength region 200~800 nm were obtained. The results indicate that the SWNTs addition can decrease the grain size of ZnO/TiO2, which can enhance the photocatalytic activity. UV-vis absorption spectra of SWNTs-ZnO/TiO2 showed obvious blue shifts compared with ZnO/TiO2. The optimal amount of doping SWNTs is 1% according to this research. The enhanced mechanism of the SWNTs for the photocatalytic activity in ZnO/TiO2 films was analyzed in this article.

Sol-Gel derived Bi4-xNdxTi3O12 Thin Films and Their Characterization

2002 ◽  
Vol 737 ◽  
Author(s):  
R.E. Melgarejo ◽  
M.S. Tomar ◽  
A. Hidalgo ◽  
R.S. Katiyar
Keyword(s):  
Thin Films ◽  
Spin Coating ◽  
Bismuth Titanate ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Complete Solid Solution ◽  
Sol Gel Process ◽  
Ferroelectric Memory ◽  
Initial Results

ABSTRACTNd substituted bismuth titanate Bi4-xNdxTi3O12 were synthesized by sol-gel process and thin films were deposited on Pt substrate (Pt/TiO2/SiO2/Si) by spin coating. Thin films, characterized by X-ray diffraction and Raman spectroscopy, shows complete solid solution up to the composition x < 1. Initial results indicate that the ferroelectric polarization increases with increasing Nd content in the film with 2Pr = 50μC/cm2 for x = 0.46, which may have application in non-volatile ferroelectric memory devices.

Expansion of Nanosized MgSiO3/Chitosan Nanocomposite Structural and Spectroscopic for Loading Velosef by Nanomaterial Intervention

2021 ◽  
Author(s):  
amal aboelnaga ◽  
talaat Meaz ◽  
amany M elnahrawy
Keyword(s):  
Antimicrobial Activity ◽  
High Performance ◽  
Sol Gel ◽  
Polymerization Process ◽  
Absorption Bands ◽  
Structural Morphology ◽  
Crystallinity Degree ◽  
Chitosan Matrix ◽  
Antimicrobial Studies ◽  
Sol Gel Process

Abstract The aim of this study is to investigate the effect of different doses of Velosef in magnesium silica/chitosan nanocomposite in terms of structural, morphology, optical properties, and bioactivity. Loading Velosef in fine-sized magnesium silica/chitosan is an efficient engineering approach for drug delivery. The sol-gel process was used to prepare magnesium silica fine-sized before being blended into chitosan matrix, which acts as a potential morphogenetic biomaterial. The Velosef/magnesium silica/chitosan nanocomposites were characterized by XRD, TEM, SEM, FTIR, UV-absorption, and antimicrobial studies. The XRD was characteristic of the crystallinity degree of the MgO-SiO2/chitosan/Velosef nanocomposites with three maximum peaks at 26.37°, 33.34o, 36.9°. FTIR results indicated the structural change occurred with the Velosef sol-gel polymerization process. UV-absorbance reveals that the MgO-SiO2/chitosan nanocomposite appeared a high performance for loading Velosef at two absorption bands at 253 and 347 nm. The MgO-SiO2/Chitosan/Velosef nanocomposites showed considerable antimicrobial activity in opposition to the tested representative microorganisms. The maximum antimicrobial activity was obtained with MgO-SiO2/Chitosan against both Escherichia coli and Candida albicans (37 mm), while the minimum antimicrobial activity (30 mm) was recorded against B. mycoides and E. coli with control.

scholarly journals Structural and Magnetic Property of Cr3+ Substituted Cobalt Ferrite Nanomaterials Prepared by the Sol-Gel Method

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2095 ◽  
Author(s):  
Jinpei Lin ◽  
Jiaqi Zhang ◽  
Hao Sun ◽  
Qing Lin ◽  
Zeping Guo ◽  
...  
Keyword(s):  
Saturation Magnetization ◽  
Sol Gel ◽  
Combustion Method ◽  
Lattice Parameter ◽  
Cubic Phase ◽  
Cobalt Chromium ◽  
X Ray Diffraction ◽  
Chromium Doping ◽  
Auto Combustion ◽  
Cr Concentration

Cobalt-chromium ferrite, CoCrxFe2−xO4 (x = 0–1.2), has been synthesized by the sol-gel auto-combustion method. X-ray diffraction (XRD) indicates that samples calcined at 800 °C for 3 h were a single-cubic phase. The lattice parameter decreased with increasing Cr concentration. Scanning electron microscopy (SEM) confirmed that the sample powders were nanoparticles. It was confirmed from the room temperature Mössbauer spectra that transition from the ferrimagnetic state to the superparamagnetic state occurred with the doping of chromium. Both the saturation magnetization and the coercivity decreased with the chromium doping. With a higher annealing temperature, the saturation magnetization increased and the coercivity increased initially and then decreased for CoCr0.2Fe1.8O4.

Synthesis and Characterizations of Strontium Substituted Hydroxyapatite Thin Films

2010 ◽  
Vol 93-94 ◽  
pp. 231-234
Author(s):  
B. Hongthong ◽  
Satreerat K. Hodak ◽  
Sukkaneste Tungasmita
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Chemical Composition ◽  
Spin Coating ◽  
Phase Structure ◽  
Sol Gel ◽  
Cross Linking ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Process

Strontium substituted hydroxyapatite(SrHAp) were fabricated both in the form of powder as reference and thin film by using inorganic precursor reaction. The sol-gel process has been used for the deposition of SrHAp layer on stainless steal 316L substrate by spin coating technique, after that the films were annealed in air at various temperatures. The chemical composition of SrHAp is represented (SrxCa1-x)5(PO4)3OH, where x is equal to 0, 0.5 and 1.0. Investigations of the phase structure of SrHAp were carried out by using X-ray diffraction technique (XRD). The results showed that strontium is incorporated into hydroxyapatite where its substitution for calcium increases in the lattice parameters, and Sr3(PO4)2 can be detected at 900°C. The SEM micrographs showed that SrHAp films exhibited porous structure before develop to a cross-linking structure.

Low-Temperature Synthesis of Nano-Crystalline ZnTiO3 Powders by Aqueous Sol-Gel Process

2014 ◽  
Vol 543-547 ◽  
pp. 3741-3744
Author(s):  
Quan Jing Mei ◽  
Cong Ying Li ◽  
Jing Dong Guo ◽  
Gui Wang ◽  
Hai Tao Wu
Keyword(s):  
Sol Gel ◽  
Zinc Nitrate ◽  
X Ray Diffraction ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
Calcination Process ◽  
X Ray ◽  
Nano Crystalline ◽  
Transmission Electron ◽  
Sol Gel Process

The ecandrewsite-type ZnTiO3was successfully synthesized by the aqueous sol-gel method using TiO2dioxide and zinc nitrate as starting materials instead of expensive organic solvent and metal alkoxides. The as-prepared nanopowders were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA) and transmission electron microscopy (TEM), respectively. The results showed that the calcination process of gel consisted of a series of oxidation and combustion reactions, accompanied by significantly exothermal effects. Highly reactive nanosized ZnTiO3powders were successfully obtained at 850 °C with particle size ~50 nm. By comparison, the aqueous sol-gel process was the most effective and least expensive technique used for the preparation of ZnTiO3nanopowders.

Sign in / Sign up

Export Citation Format

Share Document