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Utilizing the solution casting technique, polymer nanocomposites (PNCs) films including polyethylene oxide and chitosan (PEO/CS) doped with titanium dioxide nanoparticles (TiO2 NPs) as nanoceramic were successfully synthesized. The study investigated how varying TiO2 nanoparticle concentrations influenced the structural, optical properties, and antibacterial activity of the polymeric matrix. XRD patterns revealed an increase in the amorphous nature of the polymer blend as the content of TiO2 NPs inside the PEO/CS blend grew. The FT-IR analysis confirmed the interaction between TiO2 NPs and the PEO/CS blend. This confirmation is attributed to the observed vibrational changes upon the incorporation of TiO2 dopant into the polymer matrix. The UV–visible spectrum aided in the determination of optical energy band gaps (both direct and indirect), showing reductions in both Egd and Egin with higher TiO2 concentrations. SEM highlighted the partial compatibility between PEO/CS and TiO2, while transmission electron microscopy depicted spherical TiO2 NPs with diameters ranging from approximately 9 to 25 nm. Antimicrobial assessments indicated heightened efficacy in all nanocomposite samples compared to the pure PEO/CS composite, with a linear correlation to the quantity of TiO2 nanoparticles present. These findings strongly suggest the potential of these nanocomposites for food packaging applications. [ABSTRACT FROM AUTHOR]

This work explores the development and properties of novel nanocomposite materials. The nanocomposites were synthesized using a casting method and comprised blends of polyvinyl alcohol (PVA) and sodium alginate (NaAlg) with varying concentrations of silver nitrate nanoparticles (AgNO3 NPs). XRD analysis revealed an increasing trend in the amorphous character of the PVA/NaAlg blends with the addition of AgNO3 NPs. This suggests improved dispersion of the nanoparticles within the polymer matrix. FTIR results indicated the formation of potential molecular interactions between the polymer chains and the AgNO3 nanofillers, potentially influencing the overall material properties. UV–Vis spectroscopy, along with Tauc’s relation, was used to determine the direct and indirect bandgap energies of the nanocomposites. Notably, the addition of 7 wt% AgNO3 NPs led to a significant decrease in the direct bandgap energy (Eg) of the pristine PVA/NaAlg blend, from 5.03 eV to 4.69 eV. This reduction suggests improved light absorption potential within the nanocomposite. The dielectric behavior and electrical conductivity of the nanocomposite films were also investigated. Interestingly, the dielectric constant and dielectric loss exhibited an opposite trend compared to the AC conductivity. While AC conductivity increased with frequency, the dielectric constant and loss decreased. However, the study revealed a positive correlation between AgNO3 concentration and the dielectric loss and constant values, indicating an influence of AgNO3 content on the dielectric response. The fabricated PVA/NaAlg-AgNO3 nanocomposite films exhibit promising properties, including improved AC conductivity and dielectric characteristics. These findings suggest their potential application in various technological fields, such as optoelectronic devices and electrical applications. [ABSTRACT FROM AUTHOR]

This study investigates the use of organic and inorganic nanostructures to create innovative functional materials with applications in optoelectronics devices. Specifically, nanocomposite films were created by incorporating different concentrations of cesium bromide nanoparticles (5, 10, and 15 wt%) into a polyvinyl alcohol (PVA) and sodium alginate (SA) polymer blend (50/50 wt%) through a solution casting process. The impact of CsBr NPs on the structural, optical, and electrical properties of the virgin PVA/SA matrix was systematically investigated. x‐ray crystallography investigation verified the semicrystalline nature of the PVA/SA. FTIR spectra showed the main vibrational peaks of PVA/SA, with their intensity decreasing after the addition of cesium bromide. Scanning electron microscopy images showed the formation of aggregations and the increase of roughness for the PVA/SA‐CsBr NPs 15 wt% nanocomposite sample. The UV/vis. absorption spectrum showed a decrease in the energy gap values, which decreased from 4.25 to 3.89 eV in the direct transition and decreased from 4.12 to 3.77 eV in the indirect transition. Furthermore, the electrical conductivity and dielectric properties demonstrated improvement with increasing concentration of CsBr NPs. The antibacterial efficacy against Staphylococcus aureus and Escherichia coli exhibited an upward trend with an increase in CsBr nanoparticle concentration. Overall, the results suggest the promising potential of these nanocomposite films for applications in optoelectronics and biological applications. Highlights: XRD shows that the amorphousity is increased after addition CsBr NPs.FT‐IR confirms the interactions/complexation between PVA/SA polymeric matrix filled with CsBr NPs.Optical energy gap is decreased with increasing CsBr concentrations.SEM images show the prepared samples have a smooth surface and only have a few defects.By adding CsBr NPs the electrical conductivity is tremendously improved. [ABSTRACT FROM AUTHOR]

The Polyethylene glycol (PEG) and Chitosan (CS)/silver nitrate (AgNO3) thin films were prepared by utilizing the casting technique to enhance their optical, dielectric, and electrical properties. Their physicochemical characteristics were investigated using a variety of techniques. The FT‐IR study demonstrates that the addition of AgNO3 NPs results in a discernible difference in the intensities and locations of vibrational peaks of all bands, supporting the incorporation of AgNO3NPs inside the PEG/CS. The XRD analysis indicates that the peak at 2θ = 23.1° broadens and strengthens proportionally with the increase of AgNO3 NPs. This observation suggests that the incorporation of AgNO3 NPs into PEG/CS results in a greater degree of amorphous characteristics compared to the PEG/CS blend. Additionally, when the amount of AgNO3 NPs increases in the PEG/CS, the energy band gap decreases, resulting in the creation of localized states between the valence and conduction bands. These polymer nanocomposite films' electrical conductivity, dielectric constant, and dielectric loss all increased with frequency increased and showed variance for various composite concentrations. These AgNO3NPs/PEG/CS films can be promising options for frequency‐tunable nanodielectrics, flexible dielectric substrates, and bandgap‐regulated materials for upcoming microelectronic, capacitive energy storage, and optoelectronic technologies, according to the experimental results. Highlights: AgNO3NPs/PEG/CS nanocomposites films were obtained.The optical properties of the prepared films were calculated.Optical energy‐gap for prepared samples was reduced after adding AgNO3NPs.The dielectric properties of the AgNO3NPs/PEG/CS films are improved.AgNO3NPs/PEG/CS films were suggested to be used in energy storage devices. [ABSTRACT FROM AUTHOR]

Nanocomposite films comprising polyethylene oxide (PEO) and carboxymethylcellulose (CMC) were fabricated via the solution casting process, with the incorporation of copper cobaltite nanoparticles (CuCo2O4 NPs). The study investigated the impact of CuCo2O4 NPs on the structural and optical properties of the PEO/CMC polymer blend, using X-ray diffraction, Fourier transform infrared (FTIR), and ultraviolet–visible spectroscopy (UV–Vis). The Debye–Scherrer equation was utilized to determine the size of the nanoparticles, and the results showed that the nanoparticle size decreased upon dispersion within the host matrix. The FTIR spectra of PEO/CMC blends revealed distinct vibrational spectral bands. These bands exhibited variations in their intensities, signifying interactions attributed to hydrogen bonds in the polymers. Various optical parameters, including energy gap, refractive index, Urbach energy, and extinction coefficient, were examined. The transmittance of the PEO/CMC blend exhibited a decrease from 88.6 to 18.8% following the dispersion of 3 wt% CuCo2O4 NPs. The optical analysis revealed an increase in the refractive index and a reduction in the optical band gap values, which reduced from 4.37 eV in the polymer blend to 3.77 eV in samples containing 3 wt% CuCo2O4. Furthermore, an increase in Urbach energy was observed with the rise in CuCo2O4 NPs content. The study also explored the influence of CuCo2O4 NPs on the fluorescence spectra of the PEO/CMC matrix and observed an increase in both optical dielectric and optical conductivity with increasing CuCo2O4 NPs content. [ABSTRACT FROM AUTHOR]

In this study, novel flexible polymer nanocomposite films formed of polyvinyl alcohol (PVA), sodium alginate (NaAlg), titanium dioxide (TiO2) and graphene oxide (GO) as nanofiller are fabricated by using casting method. The PVA/NaAlg‐GO/TiO2 nanocomposite films are characterized using various techniques. The synergistic effects of GO/TiO2 on the electrical, dielectric properties, and the energy density efficiency of PVA/NaAlg blend have been investigated in the range of frequency from 10 Hz to 7 MHz. The XRD data showed that the intensity of the PVA/NaAlg‐GO/TiO2 nanocomposites films decrease with nanofiller concentration. The FTIR spectroscopy provides proof that the complex formed. The optical studies were carried out using UV–Vis. spectroscopy. The energy bandgap values of PVA/NaAlg‐GO/TiO2 nanocomposite films were calculated using Tauc's plot. It is shown that the host matrix's Eg value decreases from 4.97 to 4.29 eV for direct transitions and from 4.37 to 2.29 eV for indirect transitions. The electrical and dielectric parameters of the nanocomposites showed that the maximum electrical properties were observed for the composite with 8 wt% loading of GO/TiO2. The σdc increased from 2.45 × 10−9 to 5.02 × 10−7 S cm−1. In addition, frequency exponent S decreased from 0.82 to 0.54. These findings demonstrated that there are significant modifications in the fabricated samples, which open the road for utilizing the PVA/NaAlg‐GO/TiO2 nanocomposite as flexible films for solar cells and electrical energy storage applications. [ABSTRACT FROM AUTHOR]

The pure polymer polypyrrole (PPy) was employed as the host material for the solution casting fabrication of nanocomposite films reinforced with different concentrations of tetragonal titanium dioxide nanoparticles (less than 45 nm in particle size). Nanocomposite films were characterized by utilizing FTIR, XRD, SEM, UV–Vis spectroscopy and AC measurements to study their structural, optical, morphological, electrical and dielectric properties. X-ray diffraction and FTIR analysis confirmed the enhanced amorphous regions of the PPy structure and the presence of coordination and hydrogen bonds in the prepared films. SEM was utilized to investigate the surface of the synthesized samples. As evidenced by the UV–visible spectra, optical analysis revealed that the absorbance of the prepared samples had increased substantially due to the addition of titanium dioxide nanoparticles. The energy gap of the prepared samples reduced from 4.71 eV to 3.75 eV for the indirect transition as the concentration of TiO2 NPs increased. At room temperature, the inclusion of TiO2 NPs enhanced the ionic conductivity of PPy/TiO2 nanocomposites to a maximum of 4.12 × 10− 8 S/c. We also evaluated the dielectric properties of nanocomposite films, including dielectric permittivity. The parameters may be modified to produce interesting biodegradable polymer nanodielectrics by incorporating TiO2 to pure polymers. These films possess interfacial polarization, which has a confirmed relaxation process and dominating effect. These results indicate that these nanocomposites are suitable for a variety of applications, such as flexible capacitors, battery separators, and high-density energy storage systems. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites (PNCs) of Carboxymethyl cellulose (CMC)/Polyvinyl alcohol (PVA) incorporated with various quantities of MoO3 nanobelts were prepared via a casting technique. The XRD patterns depicted the orthorhombic structure of MoO3 NBs with an average crystallite size of 75.82 nm, and the crystallinity degree of nanocomposite samples significantly decreased after loading MoO3 nanobelts. The TEM image shows a nanobelt-like morphology of MoO3 powder. The ATR-FTIR spectra of the prepared PNCs established the strong interaction between CMC/PVA polymer blend and MoO3 NBs. From the spectra of the UV–Vis-NIR technique, the optical parameters of the CMC/PVA matrix could be adjusted by the NBs addition, where the optical band gap (direct and indirect) and refractive index were calculated and discussed. The dielectric dispersion and relaxation processes of CMC/PVA/MoO3 were tested over the frequency range from 0.1 Hz to 20 MHz at RT. Improved values of ε′ and ε″ for the films after adding MoO3 NBs are due to the increment in the effective parallel ordering of dipoles, resulting in increased dielectric polarization. The conductivity was enhanced after loading the MoO3 NBs owing to the improvement in the charge carriers. The frequency exponent (s) value was used to identify the conduction model in the prepared samples as a correlated barrier hopping one. These results are predicted to have a significant impact on a wide range of electric and optoelectronic applications including separators in batteries, flexible capacitors, and energy storage devices. [ABSTRACT FROM AUTHOR]

This study investigated the impact of incorporating multi-walled carbon nanotubes/titanium dioxide (MWCNT/TiO₂) nanofillers into a Polyvinyl Alcohol/Polyethylene Oxide (PVA/PEO) polymer blend on its structural, optical, electrical, and antibacterial properties. The nanocomposite films were prepared using the solution casting method, and their characterization was conducted using X-ray diffraction (XRD), Fourier transform infrared (FTIR), Ultraviolet-visible (UV–vis.) spectroscopy, dielectric analysis, and Scanning electron microscopy (SEM). The results revealed that the addition of MWCNT/TiO₂ nanofillers significantly altered the structural and optical properties of the PVA/PEO blend. The degree of crystallinity decreased progressively from 76.21 to 44.56%. The values of Egd decreased from 5.12 to 4.56, while Egi decreased from 4.22 to 3.54. The bandgap of the nanocomposites decreased with increasing nanofiller content, indicating the formation of inter/intramolecular hydrogen bonds between the nanofillers and the polymer matrix. The incorporation of MWCNT/TiO₂ also enhanced the AC conductivity and dielectric properties of the nanocomposites. The DC conductivity (σDC) increased significantly from 2.14 × 10⁻¹⁴ Ω⁻¹ cm⁻¹ to 4.71 × 10⁻⁷ Ω⁻¹ cm⁻¹ across the measured data points. Furthermore, the fabricated samples exhibited superior antibacterial activity against both Gram-positive and Gram-negative bacteria compared to the pure PVA/PEO blend. The enhanced antibacterial properties were attributed to the synergistic effects of MWCNTs and TiO₂, which can disrupt bacterial cell membranes and generate reactive oxygen species. Overall, the findings demonstrate the potential of MWCNT/TiO₂-doped PVA/PEO nanocomposites for various applications, including antimicrobial packaging, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study investigates the properties of novel flexible polymer nanocomposite films made with polyethylene glycol (PEG), sodium alginate (NaAlg), and silver nitrate (AgNO3) nanoparticles. The nanocomposites were fabricated using a casting method and characterized by various techniques to understand the influence of AgNO3 content on their optical, electrical and dielectric properties. The frequency range for characterization was 10 Hz to 7 MHz. XRD analysis revealed a decrease in the intensity of the peaks in the nanocomposite films compared to the pristine blend, suggesting changes in the crystalline structure with increasing AgNO3 concentration. FT-IR spectroscopy confirmed the successful formation of the composite material through interaction between the components. Ultraviolet-visible (UV-Vis) spectroscopy was utilized to examine the optical properties of the films. Tauc’s plot analysis was used to calculate the energy bandgap values for both direct and indirect transitions in the nanocomposites. The results showed a decrease in the bandgap (Eg) with increasing AgNO3 content. This trend was observed for both direct transitions (Eg decreasing from 5.59 eV to 5.16 eV) and indirect transitions (Eg decreasing from 4.93 eV to 3.95 eV). Electrical and dielectric characterization revealed that the nanocomposite with 20 wt% AgNO3 loading exhibited the most favorable electrical properties. The direct current conductivity (σdc) increased significantly from 2.55 × 10− 10 S/cm to 5.65 × 10− 9 S/cm, while the frequency exponent (S) decreased from 0.81 to 0.49. These observations suggest significant modifications in the electrical transport behavior of the films upon AgNO3 incorporation. The improved electrical properties make these PEG/NaAlg-AgNO3 nanocomposites promising candidates for applications in flexible solar cells and electrical energy storage devices. [ABSTRACT FROM AUTHOR]

In this study, nanocomposite films were produced by blending polyvinyl alcohol (PVA) and chitosan (Cs) polymers with 70 % PVA and 30 % Cs, incorporating silver nanoparticles (Ag NPs) via a solution-casting method. The research aims to investigate the impact of the biosynthesized Ag NPs by Chenopodium murale leaf extract on optical, morphological, mechanical, thermal, electrical, and antibacterial properties. XRD analysis showed a decrease in crystallinity degree with Ag NPs addition. TEM revealed Ag NPs in cubic and spherical shapes with an average size of 23.4 nm. SEM and AFM indicated surface morphology changes. FT-IR spectra showed interaction between Ag ions and the blend. The energy gap decreased with increasing Ag NPs concentration. TGA exhibited enhanced thermal stability. Mechanical properties improved significantly. AC electrical conductivity and dielectric parameters were studied. Antibacterial activity against Gram-positive and Gram-negative bacteria was observed. Overall, PVA/Cs-Ag NPs films show promise for food packaging and optoelectronic applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)