scholarly journals The Tungsten Oxide Within Phosphate Glasses to Investigate the Structural, Optical and Shielding Properties Variations

2021 ◽  
Author(s):  
mohammed sadeq ◽  
B.O. El-bashir ◽  
Aljawhara H. Almuqrin ◽  
M.I. Sayyed
Keyword(s):  
Band Gap ◽  
Optical Band Gap ◽  
Visible Region ◽  
Average Density ◽  
Radiation Shielding ◽  
Phosphate Glasses ◽  
Blue Color ◽  
Color Transformation ◽  
Dark Blue ◽  
Average Molar Volume

Abstract We prepared a series of sodium phosphate glasses by changing WO3/P2O5 content and investigated structure optical and radiation shielding features as a function of glass composition. The average density (ρexp) and was found to increase gradually from 2.49 to 3.07 g/cm3 while the average molar volume values reduced from 47.37 to 44.28 cm3/mol with WO3 addition. Also, the average field strength was also computed and found to increase with increasing WO3. The study of optical absorption spectra reveals that, the absorption peaks in the visible region become higher compared to the peaks In the UV region. This observation is accompanied with a color transformation of glasses from light to dark blue color, with more WO3 adding. The existence of pentavalent tungsten state (W5+) is identified by this blue color. with WO3 addition an absorption band at around at 350–390 nm is appeared. Moreover, this band is overlapped with Urbach edge, which regularly produces an artificial edge-like feature at ~400 nm. A detailed deconvolution protocol is required for an appropriate understanding of these spectra and unravelling the hidden Urbach edge. Our analysis shows that, with increasing WO3/P2O5 content, the optical band gap decreases. This behavior can be elucidated in terms of lower band gap of W (2.7 eV) than that of P2O5 (8.5 eV) and the high polarizing power W. Further, the radiation shielding parameters were investigated for the prepared glasses. WO3 addition improves these shielding parameters against radiation. Where, upon the increase of WO3 concentration, the LAC of glass material increases which leads to a decrease in HVL value. Then it is deducible that the amount of WO3 in this glass sample has an important impact on the shielding capability at lower energy values and has a slight impact at higher energy values.

scholarly journals Optical Characteristics of Some Binary and Ternary Phosphate Glasses

1995 ◽  
Vol 48 (5) ◽  
pp. 887 ◽  
Author(s):  
M Ashraf Chaudhry ◽  
Anwar Manzoor Rana ◽  
M Altaf ◽  
M Shakeel Bilal
Keyword(s):  
Band Gap ◽  
Optical Band Gap ◽  
Glass Composition ◽  
Visible Region ◽  
Band Gap Energy ◽  
Phosphate Glasses ◽  
Optical Absorption Spectra ◽  
Gap Energy ◽  
Sharp Edges ◽  
Uv Visible

The optical absorption spectra of some binary and ternary phosphate glasses are studied in the UV-visible region by using a spectrophotometer. The observed absorbance versus wavelength curves do not show any sharp edges in these glasses. The optical band gap energies are found to depend significantly on glass composition. The optical band gap energy is found to increase with increasing ZnO content in binary and ternary glass systems.

Optical band gap studies on xPb3O4–(1−x)P2O5 lead[(II,IV)] phosphate glasses

2002 ◽  
Vol 18 (4) ◽  
pp. 367-372 ◽  
Author(s):  
M Salagram ◽  
V Krishna Prasad ◽  
K Subrahmanyam
Keyword(s):  
Band Gap ◽  
Optical Band Gap ◽  
Phosphate Glasses

scholarly journals Effect of thickness on the optical properties of Gaas thin films

2013 ◽  
Vol 37 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Chitra Das ◽  
Jahanara Begum ◽  
Tahmina Begum ◽  
Shamima Choudhury
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Band Gap ◽  
Optical Band Gap ◽  
Visible Region ◽  
Solar Spectrum ◽  
Band Gap Energy ◽  
Optical Parameters ◽  
Gap Energy

Effect of thickness on the optical and electrical properties of gallium arsenide (GaAs) thin films were studied. The films of different thicknesses were prepared by vacuum evaporation method (~10-4 Pa) on glass substrates at a substrate temperature of 323 K. The film thickness was measured in situ by a frequency shift of quartz crystal. The thicknesses were 250, 300 and 500 nm. Absorption spectrum of this thin film had been recorded using UV-VIS-NIR spectrophotometer in the photon wavelength range of 300 - 2500 nm. The values of some important optical parameters of the studied films (absorption coefficient, optical band gap energy and refractive index; extinction co-efficient and real and imaginary parts of dielectric constant) were determined using these spectra. Transmittance peak was observed in the visible region of the solar spectrum. Here transmittance showed better result when thicknesses were being increased. The optical band gap energy was decreased by the increase of thickness. The refractive index increased by increasing thickness while extinction co-efficient and real and imaginary part of dielectric constant decreased. DOI: http://dx.doi.org/10.3329/jbas.v37i1.15684 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 1, 83-91, 2013

Optical and structural characterization of quadruplet and quintuplet molybdenum-containing phosphate glasses

2016 ◽  
Vol 30 (18) ◽  
pp. 1650270 ◽  
Author(s):  
Ehsan Soheyli ◽  
Mohammad Hossein Hekmatshoar ◽  
Farshad Parcham
Keyword(s):  
Transition Metal ◽  
Band Gap ◽  
Absorption Edge ◽  
Transition Metal Oxides ◽  
Optical Band Gap ◽  
Glass Network ◽  
Direct Consequence ◽  
Transition Metal Ions ◽  
Phosphate Glasses ◽  
Absorption Bands

In this work, vitreous samples were prepared in two series by normal melt-quenching technique and under controlled conditions. The amorphous nature of specimens was confirmed using XRD spectra. To perform FT-IR and UV-vis studies, the thin blown films were also prepared. Different ratios of transition metals are assumed to cause depolymerization of the phosphate glass network. Infrared spectra showed absorption bands related to characteristic bonds of phosphate. The P=O bond at about 1200 cm[Formula: see text] was observed, as a direct consequence of meta-phosphate bond group. The almost unchanged peak position and intensity of P=O bond (in the presence of two transition metal ions) indicated the glass modifying nature of transition metal oxides (TMOs). The spectra of two series are almost identical, except for 890–1100 cm[Formula: see text] range, which can be attributed to presence of second TMO in the first glass series. UV-vis spectra also showed that the absorption edge, optical band gap and Urbach energy of the prepared samples are highly dependent on the kind and percentage of their reagents. The most striking result of UV-vis measurements was increasing and decreasing of optical band gap in the first and the second series with MoO3 content, respectively. The shape of the absorption edge (a plot of [Formula: see text] versus [Formula: see text]) demonstrated the indirect nature of the band gap in the prepared specimens.

scholarly journals Characterization and Optical Properties of MnO Doped CuO-Containing Phosphate Glass as Absorption Filters

2018 ◽  
Vol 15 ◽  
pp. 5983-5996
Author(s):  
Hytham Ahmed Abd El-Ghany
Keyword(s):  
Band Gap ◽  
Phosphate Glass ◽  
Optical Band Gap ◽  
Visible Region ◽  
Glass Network ◽  
Spectroscopic Studies ◽  
Progressive Increase ◽  
Cutoff Wavelength ◽  
Xrd Patterns

In order to demonstrate the intrinsic and extrinsic changes induced by MnO in the phosphate glass network, a glass system of composition 44P2O5-38ZnO-2CuO-(16-x)Na2O-xMnO (where, x = 1, 2, 3, 4, and 5 mol%) was prepared using the conventional melt quenching technique. XRD patterns confirmed the non-crystalline nature of the prepared samples. The density and molar volume as a function of MnO content were determined to characterize structure of the obtained glasses. The optical spectroscopic studies of the prepared samples were carried out over (190-1000 nm) spectral range. The prepared samples were found to behave as bandpass filters in the visible region of spectrum. The UV cutoff wavelength was shifted from 308 nm to 352 nm by increasing content of MnO which is very useful in the optical technology requirements such as ultraviolet preventing applications and the protection from UV-LASER. The optical band gap was decreased by increasing content of MnO whilst, the Urbach energy was increased. The decrease in optical band gap was attributed to the progressive increase in non-bridging oxygens (NBOs) concentration with the addition of MnO. The refractive index was found to be enhanced with the addition of MnO by the effect of increase in overall polarizability. However, the optical polarizability was found to be correlated to the chemical composition of the glass. The results reveal the role of MnO as a network modifier in the phosphate glass matrix.

scholarly journals Structural, Magnetic and Photocatalytic Properties of BiFeO3 Nanoparticles

2017 ◽  
Vol 7 (3) ◽  
Author(s):  
Seyyed Morteza Masoudpanah
Keyword(s):  
Thermal Decomposition ◽  
Band Gap ◽  
Optical Band Gap ◽  
Visible Region ◽  
Spherical Shape ◽  
Phase Evolution ◽  
Weak Ferromagnetism ◽  
Visible Light Photocatalyst ◽  
Bifeo3 Nanoparticles ◽  
Vis Spectroscopy

Single phase BiFeO3 nanoparticles as a visible light photocatalyst were successfully synthesized by thermal decomposition of the glyoxylate precursor. The glyoxylate precursors were formed by the redox reaction between ethylene glycol and nitrate ions. The phase evolution, structure and optical properties of BiFeO3 nanoparticles were characterized by X-ray diffraction, electron microscopy and UV–Vis spectroscopy methods. The BiFeO3 nanoparticles showed the quasi spherical shape. The BiFeO3 nanoparticles synthesized at 500 °C showed the weak ferromagnetism behavior, due to the size confinement effect, in spite of the antiferromagnetic behavior of the BiFeO3 nanoparticles synthesized at 600 °C. The BiFeO3 nanoparticles exhibited strong absorption in the visible region with the optical band gap calculated from Tauc’s plot. The optical band gap decreased from 2.10 to 2.08 eV by the increasing of thermal decomposition temperature. Moreover, the BiFeO3 nanoparticles were used for the degradation of methylene blue as a typical dye pollutant under direct sunlight irradiation.

scholarly journals Optical Properties of Silver-Vanadium-Phosphate Glasses

2017 ◽  
Vol 16 (1) ◽  
pp. 1-7
Author(s):  
B Eraiah
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Band Gap ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Phosphate Glasses ◽  
Vanadium Phosphate ◽  
Tauc Plot ◽  
Uv Visible ◽  
Oxide Ions

The glasses with the composition of xAg2O-50V2O5-(50-x)P2O5 (where x = 5,10,15,20,30 and 40 mol%) were synthesized using melt quenching technique and their optical properties were carried out through UV-Visible spectrophotometer. The absorption spectra of these glasses were recorded at room temperature in the wavelength range 200-1100nm. The optical band gap energies were calculated using Tauc plot. The calculatedenergy band gap values are ranging from 2.075 to 2.834 eV. The refractive index and polarizabilities of oxide ions have been calculated using Lorentz-Lorentz relation. The calculated refractive index and polarizabilities of these glasses in the range of 2.443 to 2.703 and 9.8877×10-24 to 13.590×10-24cm3.

Transparent Conductive In-doped Cd3TeO6 Thin Films with Perovskite Structure Deposited by Radio Frequency Magnetron Sputtering

2005 ◽  
Vol 20 (9) ◽  
pp. 2256-2260 ◽  
Author(s):  
Hiroyuki Tetsuka ◽  
Yue Jin Shan ◽  
Keitaro Tezuka ◽  
Hideo Imoto ◽  
Kiyotaka Wasa
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Radio Frequency ◽  
Band Gap ◽  
Indium Tin Oxide ◽  
Optical Band Gap ◽  
Visible Region ◽  
Radio Frequency Magnetron ◽  
Radio Frequency Magnetron Sputtering ◽  
Average Transmittance

Transparent conductive In-doped Cd3TeO6 thin films were deposited on silica glass substrate by radio frequency magnetron sputtering using targets composed of CdO, TeO2, and In2O3 powders, and their electrical and optical properties were examined. The electrical resistivity of 3.2 × 10−3 Ωcm and an average transmittance above 80% in the visible region (400–800 nm) were obtained for the films deposited at the substrate temperature above 300 °C. The maximum optical band gap was 3.92 eV for the film deposited at 700 °C, demonstrating a large optical band gap comparable to indium tin oxide.

EFFECT OF B2O3 ON PHYSICAL AND OPTICAL PROPERTIES OF ZINC PHOSPHATE GLASSES

2006 ◽  
Vol 20 (26) ◽  
pp. 1637-1643
Author(s):  
M. ALTAF ◽  
M. A. CHAUDHRY ◽  
M. TARIQ BHATTI
Keyword(s):  
Band Gap ◽  
Optical Band Gap ◽  
Zinc Phosphate ◽  
Mass Density ◽  
Band Gap Energy ◽  
Phosphate Glasses ◽  
Exponential Dependence ◽  
Amorphous Nature ◽  
Sharp Edges ◽  
Band Tailing

Zinc-phosphate glasses with the addition of B 2 O 3 were prepared by using the melt quench technique. These glasses had a mol% composition of 30 ZnO -x B 2 O 3 - (70-x) P 2 O 5. The quantity x had values of 10–40 mol%. The mass density of these glasses was found to be in the range of 2.4912–3.0142 g/cm3. The oxygen packing density and molar volume were estimated to lie in the range 192.385–286.026 g-atom/liter and 46.78–31.46 cm3 respectively. The absorption spectra of these glasses were recorded in the range of 190 to 1100 nm. No sharp edges were found in the optical spectra, which confirms the amorphous nature of these glasses. The optical band gap energies were determined to be in the range of 2.40–3.00 eV. A decreasing behavior in optical band gap energy was seen due to the increasing concentration of B 2 O 3. The extent of band tailing was worked out from the Urbach plots, which showed an exponential dependence of absorption coefficients on photon energies.

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