scholarly journals Synthesis and Downconversion Emission Property ofYb2O3:Eu3+Nanosheets and Nanotubes

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Chao Qian ◽  
Tianmei Zeng ◽  
Hongrong Liu
Keyword(s):  
Electron Microscopy ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Facile Hydrothermal Method ◽  
X Ray ◽  
Transmission Electron ◽  
Phase Size ◽  
Size And Morphology ◽  
Down Conversion ◽  
The Eu

Ytterbium oxide (Yb2O3) nanocrystals with different Eu3+(1%, 2%, 5%, and 10%) doped concentrations were synthesized by a facile hydrothermal method, subsequently by calcination at 700°C. The crystal phase, size, and morphology of prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the as-prepared Yb2O3nanocrystals with sheet- and tube-like shape have cubic phase structure. The Eu3+doped Yb2O3nanocrystals were revealed to have good down conversion (DC) property and intensity of the DC luminescence can be modified by Eu3+contents. In our experiment the 1% Eu3+doped Yb2O3nanocrystals showed the strongest DC luminescence among the obtained Yb2O3nanocrystals.

Synthesis and Characterization of Lead Sulfide Nanostructures with Different Morphologies via Simple Hydrothermal Method

2016 ◽  
Vol 35 (6) ◽  
pp. 559-566 ◽  
Author(s):  
Elaheh Esmaeili ◽  
Mohammad Sabet ◽  
Masoud Salavati-Niasari ◽  
Kamal Saberyan
Keyword(s):  
Electron Microscopy ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Product Size ◽  
X Ray ◽  
Transmission Electron ◽  
Hydrothermal Approach ◽  
Size And Morphology

AbstractPbS nanostructures were synthesized successfully via hydrothermal approach with a new precursor. The products were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–Vis diffuse reflectance spectroscopy (DRS). The effect of different sulfur sources were investigated on product size and morphology.

Synthesis and upconversion luminescence properties of CaF2:Yb3+,Er3+ nanoparticles obtained from SBA-15 template

2010 ◽  
Vol 25 (10) ◽  
pp. 2035-2041 ◽  
Author(s):  
Zhiguo Xia ◽  
Peng Du
Keyword(s):  
Electron Microscopy ◽  
Upconversion Luminescence ◽  
Emission Spectra ◽  
Average Diameter ◽  
Cubic Phase ◽  
Pumping Power ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Transmission Electron

CaF2:Yb3+,Er3+ upconversion (UC) luminescence nanoparticles have been synthesized using mesoporous silica (SBA-15) as a hard template. The samples were characterized by x-ray diffraction, Fourier transform infrared spectra, field-emission scanning electron microscopy, transmission electron microscopy, and UC emission spectra, respectively. Highly crystalline cubic phase CaF2:Yb3+,Er3+ nanoparticles are uniformly distributed with an average diameter of about 40–50 nm, and the formation process is also demonstrated. The UC fluorescence has been realized in the as-prepared CaF2:Yb3+,Er3+ nanoparticles on 980-nm excitation. The UC emission transitions for 4F9/2–4I15/2 (red), 2H11/2–4I15/2 (green), 4S3/2–4I15/2 (green), and 2H9/2–4I15/2 (violet) in the Yb3+/Er3+ codoped CaF2 nanoparticles depending on pumping power and temperature have been discussed. The UC mechanism, especially the origin on the temperature-dependent UC emission intensities ratio between 2H11/2 and 4S3/2 levels, have been proposed.

Solvothermal Synthesis of CeO2 Nanoparticles

2011 ◽  
Vol 236-238 ◽  
pp. 2000-2003
Author(s):  
Yong Cai Zhang ◽  
En Ren Zhang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Absorption Spectrum ◽  
Photoelectron Spectroscopy ◽  
Solvothermal Synthesis ◽  
Oxygen Vacancies ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Ultrafine CeO2 nanoparticles were synthesized directly via solvothermal treatment of Ce(NO3)3·6H2O powder in toluene at 180 °C for 48 h, and characterized by X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and UV-vis absorption spectrum. The results from XRD, Raman and XPS revealed the formation of pure cubic phase CeO2 with some oxygen vacancies. The TEM image disclosed that the as-synthesized CeO2 comprised nanoparticles of about 5–8 nm. The UV-vis absorption spectrum showed that the as-synthesized CeO2 nanoparticles had a wide UV absorption band centered at around 326 nm (3.8 eV).

Solvothermal Synthesis and Characterization of Lithium Tantalate Nanoparticles

2014 ◽  
Vol 602-603 ◽  
pp. 19-22 ◽  
Author(s):  
Lin Qiang Gao ◽  
Hai Yan Chen ◽  
Zhen Wang ◽  
Xin Zou
Keyword(s):  
Electron Microscopy ◽  
Solvothermal Synthesis ◽  
Room Temperature ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Particle Size And Morphology ◽  
Size And Morphology

Nanoscale LiTaO3 powders with perovskite structure were synthesized using the solvothermal technique with glycol as solvent at 240°C for 12h. The powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). XRD was used to elucidate room temperature structures using Rietveld refinement. The powders were pure single pervoskite phase with high crystallinity. FESEM and TEM were used to determine particle size and morphology. The average LiTaO3 grain size was estimated to be < 200nm, and TEM images indicated that LiTaO3 particles had a brick-like morphology. In addition, the effect of the temperature on the LiTaO3 power characterisitics was also detailed studied.

Hydrothermal Synthesis and Photocatalytic Properties of Flower-Like CdS Nanostructures

2011 ◽  
Vol 335-336 ◽  
pp. 460-463 ◽  
Author(s):  
Hong Mei Wang ◽  
Da Peng Zhou ◽  
Yuan Lian ◽  
Ming Pang ◽  
Dan Liu
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Uv Light ◽  
Sulfur Source ◽  
X Ray Diffraction ◽  
Facile Hydrothermal Method ◽  
X Ray ◽  
Transmission Electron ◽  
Cds Nanostructures

Hexagonal flower-like CdS nanostructures were successfully synthesized through a facile hydrothermal method with thiourea as sulfur source. By combining the results of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), the structural and morphological characterizations of the products were performed. The photocatalytic activity of CdS nanostructures had been tested by degradation of Rhodamine B (RB) under UV light compared to commercial CdS powders, which indicated that the as-syntherized CdS nanostructures exhibited enhanced photocatalytic activity for degradation of RB. The possible growth mechanism of CdS nanostructures was proposed in the end.

scholarly journals Antimicrobial Activity of Silver Nanoparticles Synthesized Using Goat Milk against Pathogens of Selected Vegetables

2019 ◽  
pp. 1-10 ◽  
Author(s):  
T. A. Ihum ◽  
C. C. Iheukwumere ◽  
I. O. Ogbonna ◽  
G. M. Gberikon
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Goat Milk ◽  
Cubic Phase ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

This study was carried out to determine the antimicrobial activity of silver nanoparticles synthesized using goat milk against pathogens of selected vegetables. Synthesis of Silver nanoparticles was done using Goat milk, and characterized using Ultra Violet-Visible absorption spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X- ray diffraction (XRD) and Transmission Electron Microscopy (TEM). Maximum absorbance of Goat milk synthesized AgNPs was observed at 417 nm, with FTIR peaks at 3455 cm−1, 1628 cm−1, 1402 cm−1, 1081 cm−1 and 517 cm−1, indicating that proteins in Goat milk (GM) were the capping and stabilization molecules involved the synthesis of AgNPs. Transmission electron microscopy analysis showed that the biosynthesized particles were spherical in shape having a size of 10-100 nm, X- ray diffraction (XRD) pattern agreed with the crystalline nature and face-centered cubic phase of AgNPs. Evaluation of the antimicrobial activity of AgNPs synthesized using GM against the indicator strains (Staphylococcus aureus CIP 9973, Pectobacterium carotovorum Pec1, Enterobacter cloacae AS10, Klebsiella aerogenes OFM28, Proteus mirabilis UPMSD3 and Escherichia coli 2013C-3342) isolated from selected vegetables, was carried out using the Agar diffusion assay at different concentrations of 25, 75 and 100 µl/ml. The present study demonstrated that the AgNPs synthesized using Goat milk have potent biological activities, which can find applications in diverse areas.

Hydrothermal Synthesis and Photoluminescence of Eu2−xSmxSn2O7 (x = 0–2.0) Nanophosphors

2008 ◽  
Vol 8 (3) ◽  
pp. 1427-1431
Author(s):  
Hongliang Zhu ◽  
Enze Zhu ◽  
Hong Yang ◽  
Dalai Jin ◽  
Deren Yang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Solid Solutions ◽  
Hydrothermal Process ◽  
X Ray Diffraction ◽  
Efficient Energy Transfer ◽  
X Ray ◽  
Transmission Electron ◽  
Pyrochlore Type ◽  
The Eu

Eu2–xSmxSn2O7 (x = 0, 0.1, 0.5, 1.0, 1.5, and 2.0) solid solutions were successfully synthesized by a simple, mild hydrothermal process. The crystal structure, particle size, and chemical composition of the solid solutions were characterized by X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy. X-ray diffraction patterns and transmission electron microscopy images reveal that all the products were cubic pyrochlore-type Eu2–xSmxSn2O7 nano-crystals with the diameter of ∼20 nm. Due to efficient energy transfer from Sm3+ to Eu3+, the Eu2–xSmxSn2O7 (x = 0.1, 0.5, 1.0, and 1.5) nanocrystals exhibited strong 5D0 → 7F1 photoluminescence emission of Eu3+. The dominant 5D0 → 7F1 transition revealed good monochromaticity and low distortion of the Eu2–xSmxSn2O7 nanophosphors.

Synthesis of Macroporous FeS2 Nanotubes and their Electrochemical Properties

2013 ◽  
Vol 774-776 ◽  
pp. 677-681
Author(s):  
Han Tao Liao ◽  
You Rong Wang ◽  
Jia Wang ◽  
Xiao Fang Qian ◽  
Si Qing Cheng
Keyword(s):  
Electron Microscopy ◽  
Electrochemical Properties ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Particle Size And Morphology ◽  
Size And Morphology ◽  
First Time

The particle size and morphology have a strong influence on the electrochemical performance of FeS2electrodes. In this paper, a simple one-pot solvothermal method is reported for the synthesis of macroporous pyrite nanotubes for the first time. The phase composition, morphology and structure of the as-obtained products were studied by the energy dispersive spectroscopy (EDS), scanning electron microscopy, (high-resolution) transmission electron microscopy, X-ray diffraction. The electrochemical properties of the FeS2samples were also investigated. The results demonstrated that the macroporous pyrite nanotubes delivered a higher initial discharge capacity of 925.2 mAh g-1and had good capacity retention.

Hydrothermal Preparation of Ag/TiO2/GO Nanocomposites with Ammonia-Treated Graphene Oxide for Enhanced Conductivity

2020 ◽  
Vol 20 (11) ◽  
pp. 6698-6702
Author(s):  
Bo-Kyung Choi ◽  
Woong-Ki Choi ◽  
Jong-Hyun Park ◽  
Soo-Jin Park ◽  
Min-Kang Seo
Keyword(s):  
Electron Microscopy ◽  
Nitrogen Doping ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Hydrothermal Preparation ◽  
Facile Hydrothermal Method ◽  
X Ray ◽  
Transmission Electron ◽  
Enhanced Conductivity

In this study, Ag/TiO2/GO nanocomposites were successfully fabricated by a facile hydrothermal method. Nitrogen-doped GO was prepared using ammonia treatment to improve its conductivity. The Ag/TiO2/GO nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS), zeta potential, and photoluminescence spectroscopy (PL). A homogeneous dispersion of Ag/TiO2 nanoparticles was shown on the surface of GO. Increasing the nitrogen doping concentration increased hydrophilicity, thereby improving the conductivity of Ag/TiO2/GO nanocomposites.

Preparation of ITO Nano-Powder by the Method of Ammonia Complexation and Calcination

2014 ◽  
Vol 968 ◽  
pp. 76-79 ◽  
Author(s):  
Li Da Sun ◽  
Yan Jiang ◽  
Zi Jing Li ◽  
Rui Min Xiao ◽  
Shun Li Lu
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Nucleation And Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nano Powder ◽  
Transmission Electron ◽  
Tin Oxides ◽  
Size And Morphology ◽  
Nucleation And Growth Mechanism

ITO (Indium Tin Oxides) nanopowder was prepared by ammonium-calcining method. The chemical composition, morphology and crystal structure were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Base on the nucleation and growth mechanism of the powder, the temperature of heat treatment impacting on size and morphology was discussed briefly. The results showed that the nanoITO powder of particle size 20nm-40nm with well-pleasing particle shape and dispersion can be prepared at 800°C.

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