X-Ray Diffraction and Electron Optical Studies on Smectite and α-Cristobalite Associations

1972 ◽  
Vol 20 (2) ◽  
pp. 89-92 ◽  
Author(s):  
Necip Güven
Keyword(s):  
X Ray Diffraction ◽  
Optical Studies ◽  
X Ray

scholarly journals Enhanced Photocatalytic Activity of Vanadium-Doped SnO2 Nanoparticles in Rhodamine B Degradation

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
H. Letifi ◽  
Y. Litaiem ◽  
D. Dridi ◽  
S. Ammar ◽  
R. Chtourou
Keyword(s):  
Photocatalytic Activity ◽  
Rhodamine B ◽  
Crystal Size ◽  
Sno2 Nanoparticles ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
Vanadium Concentration ◽  
X Ray ◽  
Transmission Electron ◽  
20 Nm

In this paper, we have reported a novel photocatalytic study of vanadium-doped SnO2 nanoparticles (SnO2: V NPs) in rhodamine B degradation. These NPs have been prepared with vanadium concentrations varying from 0% to 4% via the coprecipitation method. Structural, morphological, and optical properties of the prepared nanoparticles have been investigated by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscope (TEM), and UV-Vis and photoluminescence (PL) spectroscopy. Structural properties showed that both undoped and SnO2: V NPs exhibited the tetragonal structure, and the average crystal size has been decreased from 20 nm to 10 nm with the increasing doping level of vanadium. Optical studies showed that the absorption edge of SnO2: V NPs showed a redshift with the increasing vanadium concentration. This redshift leads to the decrease in the optical band gap from 3.25 eV to 2.55 eV. A quenching in luminescence intensity has been observed in SnO2: V NPs, as compared to the undoped sample. Rhodamine B dye (RhB) has been used to study the photocatalytic degradation of all synthesized NPs. As compared to undoped SnO2 NPs, the photocatalytic activity of SnO2: V NPs has been improved. RhB dye was considerably degraded by 95% within 150 min over on the SnO2: V NPs.

scholarly journals Structural and Optical Studies of Potential Ferroelectric Crystal: KDP Doped TGS

2013 ◽  
Vol 6 (1) ◽  
pp. 1-9 ◽  
Author(s):  
P. R. Deepti ◽  
J. Shanti
Keyword(s):  
Infrared Detectors ◽  
Room Temperature ◽  
Grown Crystal ◽  
High Sensitivity ◽  
Ferroelectric Material ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
Ferroelectric Crystal ◽  
X Ray ◽  
Vis Spectroscopy

Triglycine sulphate (TGS), an important ferroelectric material has been widely used in the fabrication of high sensitivity infrared detectors at room temperature. Single crystals of KDP doped TGS was grown by slow evaporation method at room temperature in this study. The grown crystal was characterized by UV-Vis spectroscopy, FTIR spectroscopy, powder X-ray diffraction studies, and ferroelectric studies. KDP doped TGS crystals were found to be highly transparent and full faced. The experimental results evidence the suitability of the grown crystal for optoelectronic applications.  Keywords: Crystal growth; KDP-doped TGS; Ferroelectric studies  © 2014 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.  doi: http://dx.doi.org/10.3329/jsr.v6i1.16584 J. Sci. Res. 6 (1), 1-9 (2014)

X-ray diffraction and optical studies of three mesogens of a homologous series of alkyl cyclohexyl cyanophenyl pyrimidine

1992 ◽  
Vol 40 (1-4) ◽  
pp. 73-83 ◽  
Author(s):  
S. Gupta ◽  
B. Majumdar ◽  
P. Mandal ◽  
R. Paul ◽  
S. Paul
Keyword(s):  
Homologous Series ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
X Ray

X-ray diffraction and optical studies of fractionalized regioregular poly(3-hexylthiophene)

1998 ◽  
Vol 92 (1) ◽  
pp. 7-12 ◽  
Author(s):  
T. Kaniowski ◽  
W. Łużny ◽  
S. Nizioł ◽  
J. Sanetra ◽  
M. Trznadel
Keyword(s):  
X Ray Diffraction ◽  
Optical Studies ◽  
X Ray ◽  
Regioregular Poly

Hybrid crystal formation in thermal transformations of potassium nitrite

1965 ◽  
Vol 285 (1402) ◽  
pp. 360-369 ◽  
Keyword(s):  
Control System ◽  
Single Crystal ◽  
Thermal Transformation ◽  
Crystal Formation ◽  
Monoclinic Structure ◽  
Thermal Transformations ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
X Ray ◽  
Potassium Nitrite

A microthermostat design for single crystal studies is described which gives control of specimen temperature in the range 30 to 100°C to an accuracy of ± 0.1 degC. For X-ray diffraction experiments the furnace comprises a beryllium tube chamber. For optical studies, the control system is combined with a chamber suitable for mounting on the stage of a polarizing microscope. Temperature cycles with single crystals of potassium nitrite indicate that the thermal transformation around 40°C from a monoclinic structure to one which is probably cubic, is continuous and reversible. Hysteresis is found in the transformation; high- and low-temperature structures co-exist in a hybrid single crystal over a temperature range.

Enhanced UV Photodetector Responsivity in Porous GaN/Si(111) by Metal-Assisted Electroless Etching

2007 ◽  
Vol 31 ◽  
pp. 39-41 ◽  
Author(s):  
Lee Siang Chuah ◽  
Hassan Zainuriah ◽  
Abu Hassan Haslan
Keyword(s):  
Pore Diameter ◽  
Near Band Edge ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
Uv Photodetector ◽  
X Ray ◽  
Grown Sample ◽  
Metal Semiconductor Metal ◽  
Porous Area ◽  
Near Band Edge Peak

This paper presents the structural and optical studies of porous GaN sample compared to the corresponding as grown GaN. The samples were investigated by scanning electron microscopy (SEM), high resolution x-ray diffraction (HRXRD), and photoluminescence (PL). The porous area is very uniform, with pore diameter in the range of 80-110 nm. XRD measurements showed that the (0002) diffraction plane peak width of porous samples was slightly broader than the as-grown sample. PL measurements revealed that the near band edge peak of the porous samples were redshifted. Metal-semiconductor-metal (MSM) photodiode was fabricated on the samples. For as grown GaN sample, this detector shows a sharp cut-off wavelength at 362 nm. A maximum responsivity of 0.258 A/W was achieved at 360 nm. For the porous GaN sample, this detector shows a sharp cut-off wavelength at 364 nm. A maximum responsivity of 0.771 A/W was achieved at 363 nm.

Electron optical studies of the formation of vanadium pentoxide catalyst

1987 ◽  
Vol 45 ◽  
pp. 354-355
Author(s):  
A. Legrouri
Keyword(s):  
Electron Microscopy ◽  
Vanadium Pentoxide ◽  
High Resolution Electron Microscopy ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
X Ray ◽  
Physicochemical Changes ◽  
Structural Correlation ◽  
Resolution Electron ◽  
Xrd Techniques

The oxides of vanadium, especially vanadium pentoxide, have been extensively studied because of their interesting physical properties particularly in catalysis. Vanadium pentoxide is generally used in the oxidation and ammoxidation of hydrocarbons.This catalyst has been prepared via the thermal decomposition of ammonium metavanadate (AMV) in air. Thermogravimetric analysis (TGA), infrared spectroscopy (IRS) and x-ray diffraction (XRD) techniques together with high resolution electron microscopy (HREM) and scanning electron microscopy (SEM) have enabled us to elucidate the physicochemical changes occurring during the decomposition process.According to TGA results, the decomposition of AMV commences at 150°C and is complete by 320°C leading to vanadium pentoxide by loss of ammonia and water with the formation of two intermediate compounds, namely at 190°C, ammonium bivanadate: (NH4)2V4 O11, and at 230°C, ammonium hexavanadate AHV: (NH4)2V6O16 . Samples for structural correlation studies were prepared by heating AMV in a stream of air for 2 hours at selected temperatures of 140, 190, 230, 320 and 400°C.

Electrosynthesis and Studies on CdZnSe Thin Films

2011 ◽  
Vol 15 (1) ◽  
pp. 37-42
Author(s):  
T. Mahalingam ◽  
V. Dhanasekaran ◽  
S. Rajendran ◽  
R. Chandramohan ◽  
Luis Ixtlilco ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Band Gap ◽  
Ph Value ◽  
Bath Temperature ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
Sem Images ◽  
X Ray ◽  
Predominant Orientation ◽  
Diffraction Patterns

Electrodeposited CdZnSe thin films have been prepared at various bath temperatures. The thickness of the films was estimated between 850 nm and 1500 nm by stylus method. The X-ray diffraction patterns revealed that the polycrystalline nature with cubic structure of CdZnSe alloy thin films. Microstructural properties such as, crystallite size, dislocation density, microstrain and number of crystallites per unit area were calculated using predominant orientation of the films. SEM images revealed that the surface morphology could be tailored suitably by adjusting the pH value during deposition. The surface roughness of the film was estimated using topographical studies. Optical properties of the film were analyzed from absorption and transmittance studies. Optical band gap of the films increased from 1.67 to 1.72 eV with the increase of bath temperature from 30 to 90℃. The optical constants (refractive index (n) and extinction coefficient (k)) of CdZnSe thin films were evaluated using optical studies.

Liquid Crystalline Behavior of Mixture of Two Non-Mesogenic Compounds

2010 ◽  
Vol 428-429 ◽  
pp. 292-296
Author(s):  
J. Mahadeva ◽  
Nagappa
Keyword(s):  
Liquid Crystalline ◽  
Interfacial Area ◽  
Ammonium Bromide ◽  
Polar Group ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
X Ray ◽  
Molecular Length ◽  
Different Temperatures ◽  
The Stability

The lyotropic liquid crystalline behavior of N-Cetyl-N, N, N, Trimethyl Ammonium Bromide (CTAB) with ethylene glycol (EG) has been investigated. These compounds are non-mesogenic in nature and exhibits Sm A, Sm B and Sm G phases. The stability of the phases is investigated using X-ray diffraction and optical studies. The layer thickness and molecular length are calculated using Bragg’s equation. The interfacial area per polar group and average thickness of hydrocarbon layers are estimated for different concentrations of the mixtures at different temperatures.

Sign in / Sign up

Export Citation Format

Share Document