Synthesis of PVA/CeO2 Based Nanocomposites with Tuned Refractive Index and Reduced Absorption Edge: Structural and Optical Studies

In the current study, polymer nanocomposites (NCPs) based on poly (vinyl alcohol) (PVA) with altered refractive index and absorption edge were synthesized by means of a solution cast technique. The characterization techniques of UV–Vis spectroscopy and XRD were used to inspect the structural and optical properties of the prepared films. The XRD patterns of the doped samples have shown clear amendments in the structural properties of the PVA host polymer. Various optical parameters were studied to get more insights about the influence of CeO2 on optical properties of PVA. On the insertion of CeO2 nanoparticles (NPs) into the PVA matrix, the absorption edge was found to move to reduced photon energy sides. It was concluded that the CeO2 nanoparticles can be used to tune the refractive index (n) of the host polymer, and it reached up to 1.93 for 7 wt.% of CeO2 content. A detailed study of the bandgap (BG) was conducted using two approaches. The outcomes have confirmed the impact of the nanofiller on the BG reduction of the host polymer. The results of the optical BG study highlighted that it is crucial to address the ɛ” parameter during the BG analysis, and it is considered as a useful tool to specify the type of electronic transitions. Finally, the dispersion region of n is conferred in terms of the Wemple–DiDomenico single oscillator model.

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Polymer Composites with 0.98 Transparencies and Small Optical Energy Band Gap Using a Promising Green Methodology: Structural and Optical Properties

Polymers ◽

10.3390/polym13101648 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1648

Author(s):

Muaffaq M. Nofal ◽

Shujahadeen B. Aziz ◽

Jihad M. Hadi ◽

Wrya O. Karim ◽

Elham M. A. Dannoun ◽

...

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Polymer Composites ◽

Amorphous Phase ◽

Absorption Edge ◽

Complex Form ◽

Bandgap Energy ◽

Optical Parameters ◽

Visible Spectroscopy ◽

Uv Visible

In this work, a green approach was implemented to prepare polymer composites using polyvinyl alcohol polymer and the extract of black tea leaves (polyphenols) in a complex form with Co2+ ions. A range of techniques was used to characterize the Co2+ complex and polymer composite, such as Ultraviolet–visible (UV-Visible) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The optical parameters of absorption edge, refractive index (n), dielectric properties including real and imaginary parts (εr, and εi) were also investigated. The FRIR and XRD spectra were used to examine the compatibility between the PVA polymer and Co2+-polyphenol complex. The extent of interaction was evidenced from the shifts and change in the intensity of the peaks. The relatively wide amorphous phase in PVA polymer increased upon insertion of the Co2+-polyphenol complex. The amorphous character of the Co2+ complex was emphasized with the appearance of a hump in the XRD pattern. From UV-Visible spectroscopy, the optical properties, such as absorption edge, refractive index (n), (εr), (εi), and bandgap energy (Eg) of parent PVA and composite films were specified. The Eg of PVA was lowered from 5.8 to 1.82 eV upon addition of 45 mL of Co2+-polyphenol complex. The N/m* was calculated from the optical dielectric function. Ultimately, various types of electronic transitions within the polymer composites were specified using Tauc’s method. The direct bandgap (DBG) treatment of polymer composites with a developed amorphous phase is fundamental for commercialization in optoelectronic devices.

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Modification of optical properties of PC-PBT/Cr2O3 and PC-PBT/CdS nanocomposites by gamma irradiation

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200201 ◽

2020 ◽

Vol 92 (2) ◽

pp. 20402

Author(s):

Kaoutar Benthami ◽

Mai ME. Barakat ◽

Samir A. Nouh

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Band Gap ◽

Color Difference ◽

Band Gap Energy ◽

Polybutylene Terephthalate ◽

Γ Irradiation ◽

Gap Energy ◽

Vis Spectroscopy ◽

Oxygen Atoms

Nanocomposite (NCP) films of polycarbonate-polybutylene terephthalate (PC-PBT) blend as a host material to Cr2O3 and CdS nanoparticles (NPs) were fabricated by both thermolysis and casting techniques. Samples from the PC-PBT/Cr2O3 and PC-PBT/CdS NCPs were irradiated using different doses (20–110 kGy) of γ radiation. The induced modifications in the optical properties of the γ irradiated NCPs have been studied as a function of γ dose using UV Vis spectroscopy and CIE color difference method. Optical dielectric loss and Tauc's model were used to estimate the optical band gaps of the NCP films and to identify the types of electronic transition. The value of optical band gap energy of PC-PBT/Cr2O3 NCP was reduced from 3.23 to 3.06 upon γ irradiation up to 110 kGy, while it decreased from 4.26 to 4.14 eV for PC-PBT/CdS NCP, indicating the growth of disordered phase in both NCPs. This was accompanied by a rise in the refractive index for both the PC-PBT/Cr2O3 and PC-PBT/CdS NCP films, leading to an enhancement in their isotropic nature. The Cr2O3 NPs were found to be more effective in changing the band gap energy and refractive index due to the presence of excess oxygen atoms that help with the oxygen atoms of the carbonyl group in increasing the chance of covalent bonds formation between the NPs and the PC-PBT blend. Moreover, the color intensity, ΔE has been computed; results show that both the two synthesized NCPs have a response to color alteration by γ irradiation, but the PC-PBT/Cr2O3 has a more response since the values of ΔE achieved a significant color difference >5 which is an acceptable match in commercial reproduction on printing presses. According to the resulting enhancement in the optical characteristics of the developed NCPs, they can be a suitable candidate as activate materials in optoelectronic devices, or shielding sheets for solar cells.

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Flexible Methyl Cellulose/Polyaniline/Silver Composite Films with Enhanced Linear and Nonlinear Optical Properties

Polymers ◽

10.3390/polym13081225 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1225

Author(s):

Ali Atta ◽

Mostufa M. Abdelhamied ◽

Ahmed M. Abdelreheem ◽

Mohamed R. Berber

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Band Gap ◽

Nonlinear Optical ◽

Composite Films ◽

Methyl Cellulose ◽

Carbon Cluster ◽

Nonlinear Susceptibility ◽

Optical Parameters ◽

Flexible Polymer

In order to potentiate implementations in optical energy applications, flexible polymer composite films comprising methyl cellulose (MC), polyaniline (PANI) and silver nanoparticles (AgNPs) were successfully fabricated through a cast preparation method. The composite structure of the fabricated film was confirmed by X-ray diffraction and infrared spectroscopy, indicating a successful incorporation of AgNPs into the MC/PANI blend. The scanning electron microscope (SEM) images have indicated a homogenous loading and dispersion of AgNPs into the MC/PANI blend. The optical parameters such as band gap (Eg), absorption edge (Ed), number of carbon cluster (N) and Urbach energy (Eu) of pure MC polymer, MC/PANI blend and MC/PANI/Ag films were determined using the UV optical absorbance. The effects of AgNPs and PANI on MC polymer linear optical (LO) and nonlinear optical (NLO) parameters including reflection extinction coefficient, refractive index, dielectric constant, nonlinear refractive index, and nonlinear susceptibility are studied. The results showed a decrease in the band gap of MC/PANI/AgNPs compared to the pure MC film. Meanwhile, the estimated carbon cluster number enhanced with the incorporation of the AgNPs. The inclusion of AgNPs and PANI has enhanced the optical properties of the MC polymer, providing a new composite suitable for energy conversion systems, solar cells, biosensors, and nonlinear optical applications.

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Characteristics of Poly(vinyl Alcohol) (PVA) Based Composites Integrated with Green Synthesized Al3+-Metal Complex: Structural, Optical, and Localized Density of State Analysis

Polymers ◽

10.3390/polym13081316 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1316

Author(s):

Shujahadeen B. Aziz ◽

Muaffaq M. Nofal ◽

Hewa O. Ghareeb ◽

Elham M. A. Dannoun ◽

Sarkawt A. Hussen ◽

...

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Metal Complex ◽

Band Gap ◽

Optical Band Gap ◽

Complex Dielectric Constant ◽

Poly Vinyl Alcohol ◽

Optical Parameters ◽

Dispersion Energy ◽

Casting Technique

The influence of dispersing Al-metal complex on the optical properties of PVA was investigated using UV–visible spectroscopy. Polymer composite films with various Al3+-complex amounts in the PVA matrix were arranged by solution casting technique by means of distilled water as a widespread solvent. The formation of Al3+-metal complex was verified through Ultraviolet–visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR) examinations. The addition of Al-complex into the polymer matrix led to the recovery of the optical parameters such as dielectric constant (εr and εi) and refractive index (n). The variations of real and imaginary parts of complex dielectric constant as a function of photon wavelength were studied to calculate localized charge density values (N/m*), high-frequency dielectric constant, relaxation time, optical mobility, optical resistivity, and plasma angular frequency (ωp) of electrons. In proportion with Al3+-complex content, the N/m* values were amplified from 3.68 × 1055 kg−1 m−3 to 109 × 1055 kg−1 m−3. The study of optical parameters may find applications within optical instrument manufacturing. The optical band gap was determined from Tauc’s equation, and the type of electronic transition was specified. A remarkable drop in the optical band gap was observed. The dispersion of static refractive index (no) of the prepared composites was analyzed using the theoretical Wemple–DiDomenico single oscillator model. The average oscillator energy (Eo) and oscillator dispersion energy (Ed) parameters were estimated.

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Effect of non-annealed and annealed ZnO on the optical properties of PVC/ZnO nanocomposite films

Journal of Thermoplastic Composite Materials ◽

10.1177/08927057211038631 ◽

2021 ◽

pp. 089270572110386

Author(s):

Ali F Al-Shawabkeh ◽

Ziad M Elimat ◽

Khaleel N Abushgair

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Optical Properties ◽

Zno Nanoparticles ◽

Oscillator Strengths ◽

Nanocomposite Films ◽

Optical Parameters ◽

Zno Nanoparticle ◽

Dispersion Energy ◽

Optical Susceptibility

The goal of this study was to investigate the optical properties of the prepared polyvinyl chloride (PVC)/zinc oxide (ZnO) nanocomposite films. The PVC/ZnO nanocomposite films consist of the addition of different concentrations with both non-annealed ZnO nanoparticles and ZnO nanoparticles annealed at temperature of 700°C. The PVC/ZnO nanocomposite films by weight concentrations of (0 wt.%, 2.5 wt.%, 5 wt.% and 10 wt.%) have been prepared by the casting method. The optical absorbance and transmittance values of the composites films were measured in the wavelength range between (250 to 1100 nm) at room temperature by using the UV-1800 Shimadzu spectrophotometer. The optical properties (absorption coefficient, dielectric constant, refractive index, and optical conductivity) have been investigated by the ultraviolet (UV) spectrophotometer. The optical parameters (direct optical energy gap, excitation energy for electronic transitions, the dispersion energy, static refractive index, static dielectric constant, optical oscillator strengths, the moments of optical spectrum, linear optical susceptibility, third-order nonlinear optical susceptibility, nonlinear refractive index, high-frequency dielectric constant, the carrier concentration to the effective mass ratio, the long wavelength refractive index and the plasma frequency) were calculated. The results showed that the optical properties behavior of the PVC/ZnO nanocomposite films was found to be dependent on the ZnO concentration, and photon wavelength. In addition, the results of the study show that the optical parameters can be influenced by alter the concentration of the nonannealed and annealed a ZnO nanoparticle in the PVC polymer matrix.

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Estimation of optical parameters of silicon single crystals with different orientations

Materials Science-Poland ◽

10.2478/msp-2019-0003 ◽

2019 ◽

Vol 37 (1) ◽

pp. 65-70

Author(s):

M.M. El-Nahass ◽

H.A.M. Ali

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Single Crystals ◽

Energy Gap ◽

Optical Parameters ◽

Dispersion Energy ◽

High Frequency Dielectric Constant ◽

Single Oscillator Model ◽

Indirect Allowed Transition ◽

Single Oscillator

AbstractOptical properties of Si single crystals with different orientations (1 0 0) and (1 1 1) were investigated using spectrophotometric measurements in a spectral range of 200 nm to 2500 nm. The data of optical absorption revealed an indirect allowed transition with energy gap of 1.1 ± 0.025 eV. An anomalous dispersion in refractive index. The normal dispersion of the refractive index was discussed according to Wemple-DiDomenico single oscillator model. The oscillator energy Eo, dispersion energy Ed, high frequency dielectric constant ∈∞, lattice dielectric constant ∈L and electronic polarizability αe were estimated. The real ∈1 and imaginary ∈2 parts of dielectric constant were also determined.

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Influence of Incorporation of Gallium Oxide Nanoparticles on the Structural and Optical Properties of Polyvinyl Alcohol Polymer

10.21203/rs.3.rs-374035/v1 ◽

2021 ◽

Author(s):

Alaa Abd-Elnaiem ◽

Taymour Hamdalla ◽

Seleim Seleim ◽

T. Hanafy ◽

Mushari Aljouhani ◽

...

Keyword(s):

Refractive Index ◽

Polyvinyl Alcohol ◽

Gallium Oxide ◽

Nonlinear Optical ◽

Average Crystallite Size ◽

Combustion Method ◽

Oxide Nanoparticles ◽

Optical Parameters ◽

Casting Technique ◽

Single Oscillator Model

Abstract In the present work, gallium oxide nanoparticles (nGa2O3) are synthesized via the thermal microwave combustion method, while nanocomposites of polyvinyl alcohol (PVA) polymer with various concentrations of nGa2O3 (0, 1, 2, 3, 4, and 5 wt%) are prepared by the casting technique. The structural characterization of nGa2O3, PVA, and films of PVA-Ga2O3 nanocomposites are studied using X-ray diffraction (XRD), High-resolution transmission electron microscopy (HRTEM), and Fourier-transform infrared spectroscopy. The HRTEM and XRD examinations showed that the prepared nGa2O3 has an average crystallite size of ~ 5.6 nm and particle size of ~ 0.9 µm. On another side, the optical transmission spectra were performed in the spectral range 250 to 2500 nm at room temperature. The refractive index, absorption coefficient, and optical bandgap (Eg) were determined using the Wemple-DiDomenico single oscillator model. It was shown that Eg slightly reduced from 3.61 to 3.55 eV with increasing the Ga2O3 content to 3 wt%, while raised again up to 3.58 eV for 5 wt% Ga2O3. Other optical characteristics such as the optical density, extinction coefficient, refractive index, optical susceptibility, thermal emissivity, optical sheet resistance for the PVA-Ga2O3 nanocomposites are investigated. The linear and nonlinear optical parameters together with their dependencies on the doping ratio reveals the qualification of PVA-Ga2O3 nanocomposites for nonlinear optical applications.

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Composition Effect of Poly(3,4-Ethylenedioxythiophene):Poly(Styrene Sulphonic Acid) and Polyaniline to Dispersion and Optical Properties of Polymer Blends

Materials Science Forum ◽

10.4028/www.scientific.net/msf.846.225 ◽

2016 ◽

Vol 846 ◽

pp. 225-229 ◽

Cited By ~ 1

Author(s):

N.F.M. Sahapini ◽

Ahmad Nazib Alias ◽

Z.M. Zabidi ◽

Mohd Ashmir Yahya

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Polymer Blends ◽

Photon Energy ◽

Extinction Coefficient ◽

Sulphonic Acid ◽

Optical Parameters ◽

Normal Dispersion ◽

Casting Technique ◽

Optical Dielectric

A Polymer blends compose of Poly (3,4-ethylenedioxythiophene):Poly (styrene sulphonic acid)(PEDOT:PSS) and Polyaniline (PANi) have been prepared using drop casting technique. Optical parameters such as refractive index (n), extinction coefficient (k), reflectance, and optical dielectric were determined in this study. It is found that reflectance spectra increase as the PANi concentration decreases in the sample of small photon energy. The refractive index of the sample shows significant effect with the PEDOT:PSS concentration. As the concentration of PEDOT:PSS increases, the refractive index shows a normal dispersion behavior. Extinction coefficient decrease as the wavelength increase within the range of 300 nm to 350 nm that may contribute to the loss fraction of light due to scattering and the decreasing of absorbance at this range. However, the extinction coefficient increases from 350 nm to the maximum wavelength of 800 nm since the absorbance is also increasing. Both the real and imaginary part of the dielectric constant decreases when the photon energy increases. This revealed that the compositions of PEDOT:PSS influence the optical properties of hybrid PEDOT-PSS:PANi thin film.

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

Polymers ◽

10.3390/polym12102320 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2320 ◽

Cited By ~ 2

Author(s):

Ahang M. Hussein ◽

Elham M. A. Dannoun ◽

Shujahadeen B. Aziz ◽

Mohamad A. Brza ◽

Rebar T. Abdulwahid ◽

...

Keyword(s):

Refractive Index ◽

Band Gap ◽

Polymer Nanocomposites ◽

Absorption Edge ◽

Optical Band Gap ◽

Solid Polymer ◽

Optical Parameters ◽

Optical Dielectric Constant ◽

Solution Cast ◽

Optical Dielectric

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.

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Effect of gamma irradiation on structural, morphological and optical properties of p-quaterphenyl thin films

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v14i2.7549 ◽

2018 ◽

Vol 14 (2) ◽

pp. 5624-5637

Author(s):

A.A. Attia ◽

M.M. Saadeldin ◽

K. Sawaby

Keyword(s):

Thin Films ◽

Refractive Index ◽

Optical Properties ◽

Surface Morphology ◽

Absorption Coefficient ◽

Gamma Irradiation ◽

Band Gap ◽

Optical Band Gap ◽

Thermal Evaporation Method ◽

Single Oscillator Model

Para-quaterphenyl thin films were deposited onto glass and quartz substrates by thermal evaporation method. p-quaterphenyl thin films wereexposed to gamma radiation of Cobat-60 radioactive source at room temperature with a dose of 50 kGy to study the effect of ?-irradiation onthe structure and the surface morphology as well as the optical properties of the prepared films. The crystalline structure and the surface morphology of the as-deposited and ?-irradiated films were examined using the X-ray diffraction and the field emission scanning electron microscope. The optical constants (n & k) of the as-deposited and ?-irradiated films were obtained using the transmittance and reflectance measurements, in the wavelength range starting from 250 up to 2500 nm. The analysis of the absorption coefficient data revealed an allowed direct transition with optical band gap of 2.2 eV for the as-deposited films, which decreased to 2.06 eV after exposing film to gamma irradiation. It was observed that the Urbach energy values change inversely with the values of the optical band gap. The dispersion of the refractive index was interpreted using the single oscillator model. The nonlinear absorption coefficient spectra for the as-deposited and ?-irradiated p-quaterphenyl thin films were obtained using the linear refractive index.

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