Structure‐Optical Studies I. X‐Ray Diffraction by Addition Compounds of Halogens with Hydrophilic Organic Polymers

1947 ◽  
Vol 15 (9) ◽  
pp. 689-689 ◽  
Author(s):  
C. D. West
2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
H. Letifi ◽  
Y. Litaiem ◽  
D. Dridi ◽  
S. Ammar ◽  
R. Chtourou

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.


2013 ◽  
Vol 6 (1) ◽  
pp. 1-9 ◽  
Author(s):  
P. R. Deepti ◽  
J. Shanti

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)


1992 ◽  
Vol 40 (1-4) ◽  
pp. 73-83 ◽  
Author(s):  
S. Gupta ◽  
B. Majumdar ◽  
P. Mandal ◽  
R. Paul ◽  
S. Paul

1998 ◽  
Vol 92 (1) ◽  
pp. 7-12 ◽  
Author(s):  
T. Kaniowski ◽  
W. Łużny ◽  
S. Nizioł ◽  
J. Sanetra ◽  
M. Trznadel

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.


2007 ◽  
Vol 31 ◽  
pp. 39-41 ◽  
Author(s):  
Lee Siang Chuah ◽  
Hassan Zainuriah ◽  
Abu Hassan Haslan

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.


1994 ◽  
Vol 04 (C9) ◽  
pp. C9-195-C9-198
Author(s):  
W. Fuller ◽  
A. Mahendrasingam ◽  
A. Jaber ◽  
C. Martin ◽  
D. Hughes ◽  
...  

Author(s):  
A. Legrouri

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.


2011 ◽  
Vol 15 (1) ◽  
pp. 37-42
Author(s):  
T. Mahalingam ◽  
V. Dhanasekaran ◽  
S. Rajendran ◽  
R. Chandramohan ◽  
Luis Ixtlilco ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document