Dielectric Constant, Metallization Criterion and Optical Properties of CuO Doped TeO2-B2O3 Glasses

Copper oxide doped TeO2 – B2O3 glass system with empirical formula; [(B2O3)0.3(TeO2)0.7]1-x(CuO)x using the melt quenching method, where x = 0.0, 0.01, 0.015, 0.02, and 0.025 was combined. The glass samples’ density and molar volume were measured, followed by characterizations using the UV-Vis, Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectroscopes. The amorphous or glassy nature of glass samples was proven by the XRD spectra except for the pure borotellurite sample which showed a peak around 2θ = 20o, indicating α-TeO2 crystalline phase presence. The FTIR spectral analysis suggested the presence of BO3, TeO3 and TeO4 as the structural functional units in the glass samples. The UV-Vis spectra showed no presence of any sharply defined edges, affirming the amorphous or glassy nature of the glass materials. Physical parameters e.g. molar volume, density, oxygen packing density (OPD), inter ionic distance of Cu2+ ions, concentration of copper ion per unit volume (N), as well as the polaron radius data were presented and discussed. Also, the direct bandgap (3.8900 to 3.5900 eV) , indirect bandgap (3.3200 to 3.0800 eV), refractive index (2.318 to 2.378), dielectric constant (5.3731 to 5.6549), optical dielectric constant (4.3731 to 4.6549), refractive index based metallization criterion (0.406885 to 0.391916) and the band gap based metallization criterion (0.407431 to 0.392428) were analysed and discussed. Based on the metallization criterion and values of refractive index, the glasses are good candidates for optoelectronic and laser applications. Meanwhile, the dielectric constants’ values of the present glasses indicate their suitability bandpass filters and microelectronic substrates applications.

Optical Characteristics of Vitamin D3 Soft Gel

In this work, the linear properties of Vitamin D3-5000IU soft gel were investigated by measuring its absorption and fluorescence spectra. It was observed that there was a shift towards longer wavelength within limits (75 nm), with quantitative efficiency equal to (33.58%). The values of absorbance were used to calculate the extinction coefficient, optical refractive index, optical conductivity and optical dielectric constant values. The non-linear properties of Vitamin D3-5000IU soft gel was also studied using the Z-Scan technique by using Neodymium-doped Yttrium Garnet (Nd: YAG) continuous laser (CW) emitting in (532 nm) wavelength, by utilize open aperture to measure nonlinear absorption coefficient and close aperture (diameter 1.5mm) to measure nonlinear refractive index. The sample behaves as two-photon absorption, and the nonlinear refractive index was positive.

SYNTHESIS AND CHARACTERIZATION OF (ZNO)–(CO3O4) NANOCOMPOSITE VIA SPRAY PYROLYSIS PROCESS: THE USE OF THE BRUGGEMAN MODEL ON OPTICAL PROPERTIES PREVISION

In the present paper, (ZnO)–(Co3O4) nanocomposite thin films have been prepared by using spray pyrolysis deposition on a glass substrate at 350∘C. After that, the as-obtained films have been characterized and analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and the double beam UV-visible (UV-vis) spectrophotometer. Furthermore, the Bruggeman model is used to predict the evolution of the optical dielectric constant (real and imaginary parts: [Formula: see text] and [Formula: see text] to compare them with those obtained from the experimental results. The XRD pattern reveals that the nanocomposite film has diffraction peaks 2[Formula: see text], 36.95∘ corresponding respectively to the (220), (311) planes of cubic Co3O4 and another about of 2[Formula: see text] corresponding to the (101) plane of Wurtzite ZnO. Using the Debye Scherrer formula, the crystallite size of (ZnO)[Formula: see text]–(Co3O[Formula: see text] nanocomposite is found about 32[Formula: see text]nm, while the obtained thickness of this nanocomposite is about 780[Formula: see text]nm using the DekTak Stylus profilometer. Besides, the morphology analysis shows that the nanocomposite sample is well covered without holes and/or cracks and it has uniform dense grains. The evaluation of the transmittance, reflectance, refraction index, extinction coefficient, real and imaginary parts of dielectric constant as function of wavelength illustrates that the optical response of nanocomposite thin film (ZnO)[Formula: see text]–(Co3O[Formula: see text] depends on the influence of two mediums of pure materials ZnO and Co3O4 and their interaction. In addition, the direct band gap vs incident photon energy obtained from the Tauc plot equation shows that this nanocomposite has three values of band gap energy which are [Formula: see text][Formula: see text]eV, [Formula: see text][Formula: see text]eV (correspond to pure Co3O4 film) and [Formula: see text][Formula: see text]eV (correspond to pure ZnO film). Besides, the application of the Bruggeman equation indicates that the influence of the values of volume concentration and optical dielectric constant of the ingredient nanomaterials (ZnO and Co3O[Formula: see text] is significant on the value of the effective dielectric constant of nanocomposite thin film. The specific result of this study is the similarity between the spectra obtained from the Bruggeman model and the measured one, which proves that the application of this model is useful for the prediction of the optical properties of the composite.

Optical Properties of Lithium Borate Glass Containing Barite

Through this research we have prepared samples of glass, which includes 60 mol%B2O3 – x mol %barite – (40-x) mol %Li2O, where x= 5, 7.5, 10, and 15 mol%. The samples fabricated by the melt quenching technique. The samples are melted in alumina crucible at 1473 K for 1.5 h in an electric muffle furnace (LENTON). The glasses were casted into stainless molds, and then immediately transferred to an annealing furnance at about 400°C. The aim of this work is to determine the extent of the effect of raw barite on the physical and optical properties of this glass. The optical transmittance and reflectance spectrum of the glasses in this work were determined in the wavelength range 300–2500 nm at room temperature. The physical and optical properties of the following prepared glass samples have been determined and calculated (density, volume molar, refraction index, Optical dielectric constant, molar refractivity and electronic polarizability) for glasses prepared.

Steps Toward the Band Gap Identification in Polystyrene Based Solid Polymer Nanocomposites Integrated with Tin Titanate Nanoparticles

In the current study, the film fabrication of polystyrene (PS) based polymer nanocomposites (NCs) with tuned refractive index and absorption edge was carried out using the solution cast method. X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) light characterization techniques were performed. The structural and optical properties of the prepared films were specified. The hump of PS decreased significantly when SnTiO3 nanoparticles (NPs) were introduced. Sharp and high intense peaks of SnTiO3 NPs at a high filler ratio were observed. The crystalline size was determined for SnTiO3 NPs from the sharp crystalline peaks using Debye-Scherrer’s equation and was found to be 25.179 nm, which is close enough to that described by the supplier. Several optical parameters, such as absorption coefficient (α), refractive index (n), and optical dielectric properties, were investigated. The absorption spectra were tuned with increasing SnTiO3NPs. Upon the addition of the NPs to the PS host polymer, the absorption edge undergoes shifting to lesser photon energy sides. The optical dielectric constant (ε′) was correlated to the refractive index. The study of the optical band gap was conducted in detail using both Tauc’s model and the optical dielectric loss (ε″) parameter. The results showed that the ε″ parameter is noteworthy to be measured in the optical band gap study of materials.

A Comprehensive Review on Optical Properties of Polymer Electrolytes and Composites

Polymer electrolytes and composites have prevailed in the high performance and mobile marketplace during recent years. Polymer-based solid electrolytes possess the benefits of low flammability, excellent flexibility, good thermal stability, as well as higher safety. Several researchers have paid attention to the optical properties of polymer electrolytes and their composites. In the present review paper, first, the characteristics, fundamentals, advantages and principles of various types of polymer electrolytes were discussed. Afterward, the characteristics and performance of various polymer hosts on the basis of specific essential and newly published works were described. New developments in various approaches to investigate the optical properties of polymer electrolytes were emphasized. The last part of the review devoted to the optical band gap study using two methods: Tauc’s model and optical dielectric loss parameter. Based on recently published literature sufficient quantum mechanical backgrounds were provided to support the applicability of the optical dielectric loss parameter for the band gap study. In this review paper, it was demonstrated that both Tauc’s model and optical dielectric loss should be studied to specify the type of electron transition and estimate the optical band gap accurately. Other parameters such as absorption coefficient, refractive index and optical dielectric constant were also explored.

Optical and dielectric properties of lead perovskite and iodoplumbate complexes: an ab initio study

Optical and dielectric properties, and energetic stability orders of black phase of perovskites and yellow phase of iodoplumbates have been studied using density functional theory; where the optical dielectric constant varies with the polymorphic phase and nature of cation.

Temperature effect on structural and optical properties of V2O5 thin films prepared by spray pyrolysis technique

In this work, the effect of substrate temperature on structural and optical properties of V2O5 thin films has been characterized by X-ray diffraction (XRD); SEM and transmission. The films mince has been prepared by Reactive Chemical Spraying technology in Liquid Phase (RCSLP) on glass substrates preheated at (350, 400, 450 and 500 °C). The X-ray diffraction analysis confirms that all layers are polycrystalline, and the preferred orientation of V2O5 is the (001) plane. The morphology of V2O5 thin films are porous nature and their particle’s shape is three-dimensional. The transmittance and absorbance of thin film were measured from which the optical constants (Energy gap, Refractive index, Absorption coefficient, Extinction coefficient and Optical dielectric constant) were determined.

Evaluation of the Structural Phase Transition in Multiferroic (Bi1−x Prx)(Fe0.95 Mn0.05)O3 Thin Films by A Multi-Technique Approach Including Picosecond Laser Ultrasonics

Picosecond laser ultrasonics is an experimental technique for the generation and detection of ultrashort acoustic pulses using ultrafast lasers. In transparent media, it is often referred to as time-domain Brillouin scattering (TDBS). It provides the opportunity to monitor the propagation of nanometers-length acoustic pulses and to determine acoustical, optical, and acousto-optical parameters of the materials. We report on the application of TDBS for evaluating the effect of Praseodymium (Pr) substitution on the elasticity of multiferroic (Bi1−xPrx)(Fe0.95Mn0.05)O3 (BPFMO) thin films. The films were deposited on Si and LaAlO3 (LAO) substrates by a sol-gel method. X-ray diffraction and Raman spectra revealed earlier that a phase transition from rhombohedral to tetragonal structure occurs at about 15% Pr substitution and is accompanied by the maxima of remnant magnetization and polarization. Combining TDBS with optical spectral reflectometry, scanning electron microscopy, and topographic measurements by atomic force microscopy, we found that the structural transition is also characterized by the maximum optical dielectric constant and the minimum longitudinal sound velocity. Our results, together with earlier ones, suggest that BiFeO3-based films and ceramics with compositions near phase boundaries might be promising materials for multifunctional applications.