scholarly journals Structural and spectroscopic analyses of copper doped P2O5-ZnO-K2O-Bi2O3 glasses

2015 ◽  
Vol 9 (3) ◽  
pp. 169-173 ◽  
Author(s):  
Yahia Elbashar

Homogeneous glass samples with different compositions 42(P2O5)?40 (ZnO)?(16?x)(K2O)?2 (Bi2O3)?x(Cu2O) (where x = 1, 2 and 3mol%) were prepared by conventional melt-quenched technique under controlled conditions. The structure of the prepared glass samples was investigated by X-ray diffraction. Optical properties (transmittance and reflectance) of the glasses were measured in the wavelength range 200-900 nm. The optical band gap energy of the investigated glasses with 1, 2 and 3mol% Cu2O was estimated from absorption data using the Mott and Davis relation and found to be 2.33, 2.45 and 2.53 eV, respectively. The mechanism of optical absorption was found to be direct. The band tail width was also estimated and found to lay in the acceptable range. Refractive index, absorption coefficient, extinction coefficient and real/imaginary parts of dielectric constants were calculated. Further to this, some theoretical investigation of the spectral problems was carried out. The investigation was based on finite difference method.

2017 ◽  
Vol 31 (16) ◽  
pp. 1750180 ◽  
Author(s):  
K. Chandra Sekhar ◽  
Abdul Hameed ◽  
G. Ramadevudu ◽  
M. Narasimha Chary ◽  
Md. Shareefuddin

Lead halo borate glass systems containing manganese ions have been investigated to study the role of halide ions on the physical, optical and EPR studies. The amorphous phase of the prepared glass samples [Formula: see text]PbX2–(30[Formula: see text])PbO–69.5B2O3–0.5MnO2 with X = F, Cl and Br and [Formula: see text] mol% was confirmed from their X-ray diffraction spectra. Ionic radii of the halides played an important role in the physical properties. From the optical absorption spectra, optical band gap and Urbach energy values were evaluated. The EPR spectra have shown a six-line hyperfine (HF) structure centered at [Formula: see text] and attributed to Mn[Formula: see text] centers in octahedral symmetry. The other signals at [Formula: see text] and 4.3 were attributed to the rhombic surroundings of Mn[Formula: see text] ions. The negative shift in [Formula: see text]-value revealed highly ionic environment around the Mn[Formula: see text] ion in the glass hosts. The HF splitting constant (A), number of spins (N) and susceptibility [Formula: see text] values of the prepared glasses were also reported.


2021 ◽  
Vol 12 (6) ◽  
pp. 7927-7941

Neodymium-doped Na2O-ZnO-TeO2 (NZT) glasses were prepared by the conventional melt quenching technique. DTA and TG were used to confirm glass preparation through the glass transition temperature at 447°C for the glass system. The analysis of FTIR spectra and X-ray diffraction described the samples' nature as ionic and amorphous, respectively. The optical band gap energy was estimated using absorption spectra and found to be decreased from 2.63eV to 1.32 eV due to the increase of doping concentration. The intensity of the emission spectra was enhanced for the higher concentration of Nd3+ ions. The dielectric constant of the glass samples was found to be constant for the large range of frequency (3 kHz to 1 MHz). The variation of conductivity with the temperature of the samples had shown the Arrhenius mechanism of conduction.


2021 ◽  
Author(s):  
Sabrina Roguai ◽  
Abdelkader Djelloul

Abstract Iron-doped tin dioxide nanoparticles Sn1-xFexO2 (0% ≤ x ≤ 10% ), were prepared by coprecipitation method. X-ray diffraction (XRD) patterns indicate that Sn1-xFexO2 nanoparticles (NPs) crystallize in the tetragonal rutile-like structure. Scanning Electron Microscope (SEM) observations did not show more modification of the SnO2 morphology with Fe addition. All the results are consistent with the fact that Fe is strongly soluble in SnO2 host. The optical band gap energy decreased from 3.65 to 3.30 eV with increasing the iron doping concentration in the solution. Finally, the photocatalytic efficiency of Fe0.05Sn0.95O2 nanoparticles (NPs) was examined for the degradation of MB in aqueous solution under UV irradiation. It was found that smaller bandgap of Fe doped SnO2 photocatalyst resulted in a prominent increase in photocatalytic activity of nanoparticles against Methylene Blue (MB) under UV irradiaion.


2013 ◽  
Vol 832 ◽  
pp. 734-738 ◽  
Author(s):  
S.K.M. Maarof ◽  
M.G.M. Zufrian ◽  
M.F. Achoi ◽  
Mohamad Rusop ◽  
Saifollah Abdullah

This paper will present on preparation and characterizations of hybrid nanoTiO2/ZnO using sol-gel spin coating techniques. The study involved of modification band-gap energy of Titanium Dioxide (TiO2) at different precursor molecular concentration of Zinc oxide (ZnO). The FESEM (Field emission scanning electron microscope) morphological characterize shows TiO2 and ZnO particle produced at nanoscale size. The compositional of both particles confirmed using EDAX (Energy Disperse Analyzer X-ray) analysis. The XRD (X-Ray diffraction) characterize measured the structural properties of anatase and rutile for TiO2 as well as zincite for ZnO. By increasing ZnO molecular concentration, the crystallite size, d were decreased until the optimum sample, ratio of 4 TiO2 : 1 ZnO, with value of 23.71 nm. For UV-VIS (Ultra-Violet/Visible Spectroscopy) measurement, we found the optical band-gap increased with increasing ZnO molecular concentration. The optical band-gap for optimum sample was 3.38 e.V represented this study has successfully improved the optical band-gap of TiO2.


2012 ◽  
Vol 545 ◽  
pp. 161-164
Author(s):  
Rusdi Roshidah ◽  
Abd Rahman Azilah ◽  
Norlida Kamarulzaman

ZnO is known as an inorganic material that has a variety of morphologies. The morphologies of the ZnO are much influenced by the synthesis route. In this work, two ZnO nanomaterials were prepared by the sol-gel route and the effect of detergent on the morphology and optical band gap of ZnO materials were investigated. The synthesized ZnO materials were characterized using Simultaneous Thermogravimetric Analyzer (STA), X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM). The UV-Vis spectrophotometer is used to determine the optical band gap. The results show that the presence of detergent affected the morphology of the ZnO from nanorods to nano-flakes. The band gap energy of the ZnO were also reduced from 3.14 ev to 2.98 eV from the nanorod to the nanoflakes.


2012 ◽  
Vol 584 ◽  
pp. 207-211 ◽  
Author(s):  
Vijaya Chikkaveeraiah Veeranna Gowda ◽  
K.R Sardar Pasha ◽  
M. Sudhakar Reddy ◽  
C. Narayana Reddy

Abstract. Neodymium doped sodium bismuth borate (Na2O-Bi2O3-B2O3) glasses were prepared by melt quenching method. Amorphous nature of the glass is confirmed through the X-ray diffraction study. Density of the investigated glasses increases systematically with Bi2O3 concentration. Glass transition temperature decrease slightly with increase of Bi2O3 content and could be due to increase in the number of weaker Bi-O linkages by stronger Nd-O linkages. Fourier Transform - Infrared (FTIR) spectroscopy has been carried out. The IR spectra of the glasses reveal that the strong network consisting of diborate units and is unaffected by the variation of Nd3+ concentration. UV-Visible absorption studies have been performed on these glasses to examine the optical spectra and the optical band gap energy has been calculated. The intensity of the absorption band increases with the increase of Nd3+ concentration. This is due to the formation of non-bridging oxygens (NBO’s) in the structure.


2019 ◽  
Vol 15 (34) ◽  
pp. 1-14
Author(s):  
Bushra A. Hasan

Lead selenide PbSe thin films of different thicknesses (300, 500, and 700 nm) were deposited under vacuum using thermal evaporation method on glass substrates. X-ray diffraction measurements showed that increasing of thickness lead to well crystallize the prepared samples, such that the crystallite size increases while the dislocation density decreases with thickness increasing. A.C conductivity, dielectric constants, and loss tangent are studied as function to thickness, frequency (10kHz-10MHz) and temperatures (293K-493K). The conductivity measurements confirm confirmed that hopping is the mechanism responsible for the conduction process. Increasing of thickness decreases the thermal activation energy estimated from Arhinus equation is found to decrease with thickness increasing. The increase of thickness lead to reduce the polarizability α while the increasing of temperature lead to increase α.


2011 ◽  
Vol 239-242 ◽  
pp. 2752-2755
Author(s):  
Fan Ye ◽  
Xing Min Cai ◽  
Fu Ping Dai ◽  
Dong Ping Zhang ◽  
Ping Fan ◽  
...  

Transparent conductive Cu-In-O thin films were deposited by reactive DC magnetron sputtering. Two types of targets were used. The first was In target covered with a fan-shaped Cu plate of the same radius and the second was Cu target on which six In grains of 1.5mm was placed with equal distance between each other. The samples were characterized with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV/VIS spectrophotometer, four-probe measurement etc. SEM shows that the surfaces of all the samples are very smooth. EDX shows that the samples contain Cu, In as well as O, and different targets result in different atomic ratios of Cu to In. A diffraction peak related to rhombohedra-centered In2O3(012) is observed in the XRD spectra of all the samples. For both the two targets, the transmittance decreases with the increase of O2flow rates. The direct optical band gap of all the samples is also estimated according to the transmittance curve. For both the two targets, different O2flow rates result in different sheet resistances and conductivities. The target of Cu on In shows more controllability in the composition and properties of Cu-In-O films.


2021 ◽  
Author(s):  
Rahma Rahzelli Zrelli ◽  
Fathia Chehimi-Moumen ◽  
Dalila Ben Hassen-Chehimi ◽  
Malika Trabelsi-Ayadi

Abstract The synthesis of the diphosphate HYP2O7·3H2O was made via soft chemistry route from evaporation of aqueous solution at room temperature. The obtained compound, was characterized by means of X-ray diffraction (XRD) and infrared spectroscopy (IR). The results showed a high purity phase. IR spectrum of this diphosphate revealed usual signals related to P2O7 diphosphate group and water molecules. The thermal decomposition of the synthesized product by DTA / TG proceeded through four stages leading to the formation of the Y2P4O13 as a final product. On the other hand, its decomposition by CRTA took place in three stages leading to the formation of the anhydrous diphosphate HYP2O7 as a final product. X-ray powder diffraction and infrared spectroscopy were used to identify these materials. Furthermore the electrical properties of the HYP2O7 were investigated through impedance complex analysis. Modest conductivity has been observed in this material at relatively medium temperature range. Activation energy of 0.67 and 1.44 eV, was deduced from the corresponding Arrhenius plot.The optical band gap of the title compound is calculated and found to be 2.71 eV.


2021 ◽  
Vol 317 ◽  
pp. 95-99
Author(s):  
Muhammad Noorazlan Abd Azis ◽  
Halimah Mohamed Kamari ◽  
Suriani Abu Bakar ◽  
Azlina Yahya ◽  
Umar Saad Aliyu

Borotellurite glass had been widely applied in the field of optical communications and devices. In this work, holmium oxides doped borotellurite glass had been successfully fabricated via conventional melt-quenched technique. The structural properties of holmium doped tellurite glass were found using x-ray diffraction (XRD) method. The nonexistence of sharp peaks in XRD pattern shows that the inclusion of holmium tellurite glass leads to the formation long range of disorderness. The optical properties of the glass system such as refractive index and optical band gap energy are investigated using UV-Vis spectrophotometer. The value of refractive index is found in nonlinear trend along with holmium oxides concentration. It is found that the refractive index is more than 2 at 0.01, 0.03 and 0.04 of holmium concentrations. The optical band gap energy was found in similar trend with refractive index which is in nonlinear pattern.


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