SYNTHESIS OF MONODISPERSE Mn3O4 NANOCRYSTALS

2009 ◽  
Vol 08 (03) ◽  
pp. 281-283 ◽  
Author(s):  
MASOUD SALAVATI-NIASARI ◽  
FATEMEH DAVAR
Keyword(s):  
Photoelectron Spectroscopy ◽  
Average Diameter ◽  
Binding Energies ◽  
X Ray Diffraction ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
20 Nm

Mn3O4 nanocrystals have been prepared using [bis(2-hydroxyacetophenato)manganese(II)] as precursor. Transmission electron microscopy analysis demonstrated nanocrystals Mn3O4 with an average diameter of about 20 nm. The structural study by X-ray diffraction indicates that these nanocrystals have pure tetragonal phase. The phase pure samples were characterized using X-ray Photoelectron Spectroscopy for Mn 2p level. The values of binding energies are consistent with the relative values reported in the literature.

FORMATION OF TWO LAYERS IN Pr1-xCaxBa2Cu3O7-y(0≤x≤0.5) THIN FILMS DEPOSITED AT DIFFERENT TEMPERATURES

2000 ◽  
Vol 14 (16) ◽  
pp. 1651-1657
Author(s):  
J. A. DÍAZ ◽  
O. CONTRERAS ◽  
J. M. SIQUEIROS
Keyword(s):  
Thin Films ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Cell Parameters ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
Different Temperatures ◽  
Microscopy Analysis

We have grown epitaxial Pr 1-x Ca x Ba 2 Cu 3 O 7-y(0≤x≤0.5) thin films on SrTiO 3 and Yttrium stabilized zirconia (YSZ) substrates by pulsed laser deposition at different temperatures. X-ray diffraction and transmission electron microscopy analysis revealed epitaxial growth on YSZ substrates for x=0 along the a and c axis directions for T=570° C , where first the film grows oriented along a-axis and afterward, it undergoes a shift in the orientation, growing in the c-axis direction from then on. The cell parameters were c=1.166 nm and a~b=0.386 nm .

Growth and Characterization of C-Axis Oriented YBa2Cu3O7-x/PrBa2Cu3O7-x Bilayers

1999 ◽  
Vol 13 (09n10) ◽  
pp. 1005-1010 ◽  
Author(s):  
C. Beneduce ◽  
F. Bobba ◽  
M. Boffa ◽  
M. C. Cucolo ◽  
A. M. Cucolo ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
X Ray Diffraction ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Resistivity Measurements ◽  
Transmission Electron ◽  
High Oxygen Pressure ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

We report on the preparation and characterization of YBa 2 Cu 3 O 7-x/ PrBa 2 Cu 3 O 7-x bilayers onto (100) SrTiO 3 substrates. The samples have been prepared by sequential dc sputtering processes in high oxygen pressure from stoichiometric targets. The structural characterization of the YBa 2 Cu 3 O 7-x and PrBa 2 Cu 3 O 7-x films and of the bilayers has been performed by means of X-ray diffraction. The Scanning Electron Microscopy analysis has showed that the film surfaces are flat and free of precipitates. A detailed study of the interfaces has been performed by Transmission Electron Microscopy analysis. The electrical resistivity measurements showed for the YBa 2 Cu 3 O 7-x films sharp superconducting transitions at 91.5 K and critical current density of about 106 A/cm 2 at 77 K, while for the PrBa 2 Cu 3 O 7-x films a semiconductor-like behavior has been observed.

X-ray diffraction and transmission electron microscopy analysis of ordering and structure in Al1−xInxAs thin films

2000 ◽  
Vol 15 (1) ◽  
pp. 45-55 ◽  
Author(s):  
R. L. Forrest ◽  
J. Kulik ◽  
T. D. Golding ◽  
S. C. Moss
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Short Range ◽  
X Ray Diffraction ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Transmission Electron ◽  
Short Range Ordering ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

This paper presents an x-ray diffraction and transmission electron microscopy analysis of Al1−xInxAs grown by molecular beam epitaxy. Two samples grown on (001) InP at temperatures of 370 and 400 °C are characterized. The first, which contains a high density of twin lamellae, exhibits triple-period short-range ordering with a rather short correlation range normal to the (111) planes. Within these (individual) planes, the concentration, however, is uniform over a considerably greater distance, leading to a highly anisotropic scattering. This is the first observation of triple-period short-range ordering in a sample that exhibits 2 × 1 surface reconstruction. The second sample exhibits CuPt-type short-range ordering with scattering that is significantly streaked, suggestive of lamellar-shaped ordered domains. Both samples contain high densities of stacking faults leading to additional sharp streaking along symmetry-allowed 〈111〉 directions.

scholarly journals S tudies on the phase transitions and properties of tungsten (VI) oxide nanoparticles by X - Ray diffraction (XRD) and thermal analysis

2017 ◽  
Vol 26 (1) ◽  
Author(s):  
S.F. Abdullah ◽  
S. Radiman ◽  
M.A. Abdul Hamid ◽  
N.B. Ibrahim
Keyword(s):  
Thermal Analysis ◽  
Phase Transitions ◽  
Photoelectron Spectroscopy ◽  
Average Diameter ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Scherrer Formula

Tungsten (VI) oxide, WO3nanoparticles were synthesized by colloidal gas aphrons(CGAs) technique.The resultant WO3nanoparticleswere characterized by thermogravimetric-differential thermal analysis (TG-DTA) and X-Ray diffraction (XRD) measurements in order to determine the phase transitions, the crystallinity and the size of theWO3nanoparticles. As a comparison, transmission electron microscope (TEM) was used to investigate the size of the WO3nanoparticles. The result from XRD and DTA show that the formation of polymorphsWO3nanoparticles have the following sequence: orthorhombic (b-WO3)®monoclinic (g-WO3) ®triclinic (d-WO3) ®monoclinic (e-WO3) with respect to the calcination temperature of 400, 500, 600 and 700°C. No diffraction peaks were found in the X-Ray diffraction measurements for the sample heat treated at 300°C (as-prepared), suggesting that an amorphous structure was obtained at this temperature whereas the crystallinity had been obtained by the other samples of theWO3nanoparticles at the calcination temperatures of 400, 500, 600 and 700°C. It is also found that the X-Ray diffraction measurements produced an average diameter of (30 ±5), (50 ±5), (150 ±10) and (200 ±10) nm at calcination temperatures of 400, 500, 600 and 700°C respectively by using Debye-Scherrer formula. The TG curve revealed that the WO3nanoparticles is purely anhydrous since the weight loss is insignificant (0.3 –1.4) % from 30 until 600°C for the WO3nanoparticles calcined at 400°C. Finally, the composition and the purity of the WO3nanoparticleshave been examined by X-Ray photoelectron spectroscopy (XPS). Theresults indicate no significant changes to the composition and the purity of the WO3nanoparticle produced due to the temperature variations 

scholarly journals Studies on the phase transitions and properties of tungsten (VI) oxide nanoparticles by X-Ray diffraction (XRD) and thermal analysis

2017 ◽  
Vol 26 (1) ◽  
pp. 13-20 ◽  
Author(s):  
S.F. Abdullah ◽  
S. Radiman ◽  
M.A. Abdul Hamid ◽  
N.B, Ibrahim
Keyword(s):  
Thermal Analysis ◽  
Phase Transitions ◽  
Photoelectron Spectroscopy ◽  
Average Diameter ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Scherrer Formula

Tungsten (VI) oxide, WO3 nanoparticles were synthesized by colloidal gas aphrons (CGAs) technique.  The resultant WO3 nanoparticles were characterized by thermogravimetric-differential thermal analysis (TG-DTA) and X-Ray diffraction (XRD) measurements in order to determine the phase transitions, the crystallinity and the size of the WO3 nanoparticles. As a comparison, transmission electron microscope (TEM) was used to investigate the size of the WO3 nanoparticles.  The result from XRD and DTA show that the formation of  polymorphs WO3 nanoparticles have the following sequence: orthorhombic (bWO3) ® monoclinic (g-WO3) ® triclinic (d-WO3) ® monoclinic (e-WO3) with respect to the calcination temperature of 400, 500, 600 and 700°C.  No diffraction  peaks were found in the X-Ray diffraction measurements for the sample heat treated at 300°C (as-prepared), suggesting that an amorphous structure was  obtained at this temperature whereas the crystallinity had been obtained by the other samples of the WO3 nanoparticles at the calcination temperatures of 400, 500, 600 and 700°C.  It is also found that the X-Ray diffraction measurements produced an average diameter of (30 ± 5), (50 ± 5), (150 ± 10) and (200 ± 10) nm at calcination temperatures of 400, 500, 600 and 700°C respectively by using  Debye-Scherrer formula.  The TG curve revealed that the WO3 nanoparticles is purely anhydrous since the weight loss is insignificant (0.3 – 1.4) % from 30 until  600°C for the WO3 nanoparticles calcined at 400°C.  Finally, the composition and the purity of the WO3 nanoparticles have been examined by X-Ray photoelectron spectroscopy (XPS).  The results indicate no significant changes to the composition and the purity of the WO3 nanoparticles produced due to the  temperature variations.                                             

Electron Microscopy Studies of Potassium Sodium Niobate Ceramics

2005 ◽  
Vol 11 (6) ◽  
pp. 572-580 ◽  
Author(s):  
Darja Jenko ◽  
Andreja Benčan ◽  
Barbara Malič ◽  
Janez Holc ◽  
Marija Kosec
Keyword(s):  
Electron Microscopy ◽  
Secondary Phase ◽  
Nominal Composition ◽  
Potassium Sodium Niobate ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Transmission Electron ◽  
Ferroelectric Domains ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

Using electron microscopy, K0.5Na0.5NbO3 (KNN) ceramics sintered at 1030°C for 8 h and 1100°C for 2 and 24 h was studied. The scanning electron microscopy and X-ray spectrometry revealed that the materials consisted of a matrix phase in which the (Na+K)/Nb ratio corresponded closely to the nominal composition and a small amount of Nb-rich secondary phase. A bimodal microstructure of cube-shaped grains was revealed in the fracture and thermally-etched surfaces of the KNN. In the ceramics sintered at 1100°C, the larger grains (up to 30 μm across), contained angular trapped pores. The transmission electron microscopy analysis revealed that the crystal planes of the grains bordering the intragranular pore faces were of the {100} family with respect to the simple perovskite cell. Ferroelectric domains were observed in the grains of this material.

scholarly journals Physical Characteristics of Titania Nanofibers Synthesized by Sol-Gel and Electrospinning Techniques

2010 ◽  
Vol 5 (1) ◽  
pp. 155892501000500 ◽  
Author(s):  
Soo-Jin Park ◽  
Yong C. Kang ◽  
Ju Y. Park ◽  
Ed A. Evans ◽  
Rex D. Ramsier ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Average Diameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Ceramic Nanofibers ◽  
Titania Nanofibers

Titania nanofibers were successfully synthesized by sol-gel coating of electrospun polymer nanofibers followed by calcining to form either the pure anatase or rutile phases. Characterization of these materials was carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy techniques. The average diameter of these ceramic nanofibers was observed to be around 200 nm for both the rutile and anatase forms. The valence band structure and optical absorption thresholds differ, however, indicating that nanofibrous mats of titania can be selectively developed for different applications in catalysis and photochemistry.

Sign in / Sign up

Export Citation Format

Share Document