The present study was conducted to explore the impact of corn starch nanoparticles (CSNPs) on the morphological, optical, and dielectric behaviors of the PVA/PMMA/PAAm (PPP) hybrid polymer matrix. The resultant PPP-CS nanocomposite films were synthesized employing the solvent casting procedure. Scanning electron microscope(SEM) images of the as-synthesized films revealed the successful embedding, homogeneity, and fine dispersion of CSNPs within the host PPP. No changes in the infrared ray(IR) band positions were seen upon embedding. The absorbance-λ chart illustrated an absorption band at 220 nm with red-shift toward higher wavelengths, which points out the semi crystalline structure of PPP-CS films. The optical coefficients were improved upon inclusion of CSNPs. The optical bandgap energy reduces from 4.50 to 4.12 eV as CSNPs’ weight percentage increases from 0 wt% to 4 wt%. Furthermore, the refractive index values for PPP-CS films are in the range of 0.5 and 2.5. The dielectric constants of the obtained films decreased with the increase in CSNPs, except for the conductivity. The embedding of a small amount of CSNPs into the hydrophilic matrix significantly improved the composite’s bioactivity. The inhibition zone diameters of Staphylococcus aureus bacteria were calculated to be 0, 26, and 32 mm for 0 wt%, 2 wt%, and 4 wt% CSNPs, respectively. The findings of this study are significant for the development of novel nanocomposite materials with antibacterial activity for optoelectronic device applications.

The current study used the spray pyrolysis method to prepare tin oxide, manganese oxide, and SnO₂/Mn₃O₄ hybrid bilayer thin films. The primary solutions for the deposition process were produced utilizing the sol-gel method. X-ray diffraction, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, and photoluminescence spectroscopy were used to analyze the grown films. XRD spectrum of SnO_2, Mn₃O₄, and SnO₂/Mn₃O₄ hybrid bilayer thin film shows that SnO₂ thin film has a polycrystalline structure with a tetragonal cassiterite phase, Mn₃O₄ thin film shows a lower crystallinity degree due to the powdery nature of its surface, and XRD pattern of SnO₂/Mn₃O₄ hybrid thin film has a polycrystalline structure. From the FESEM, the surface morphology of SnO₂ thin film is crack-free and regular with incessant grain distribution. FESEM micrographs of the synthesized Mn₃O₄ thin film and the perfectly spherical grains of Mn₃O₄ are uniform and entirely separate, with an average size of less than 50 nm. FESSEM micrographs of SnO₂/Mn₃O₄ hybrid thin film exhibit an uneven and porous polycrystalline structure with polyhedral granulation. The film's antibacterial properties were evaluated for standard gram-negative bacteria (GNB) and gram-positive bacteria (GPB), namely Staphylococcus aureus and Escherichia coli. According to the results, the hybrid bilayers have demonstrated better antibacterial properties than tin oxide and manganese oxide monolayers. These findings ascertain the role the hybrid thin film nanocomposites play in the biomedical field's potential applications.

In the current research, silver nanoparticles (AgNPs) were mixed with a polymer blend to enhance their optical and electrical properties and antibacterial efficiency. A novel approach via introducing AgNPs into the polymer blend could improve the physical and antibacterial characteristics of the nanocomposites (NCs). In the loading process, two different amounts of AgNPs were respectively encapsulated with polyvinyl alcohol (PVA), polyacrylamide (PAAm) and polyethylene oxide (PEO) polymeric blend via casting method. The prepared films were characterized by X-ray, optical microscope (OM), scanning electron microscopy (SEM), Fourier transformation infrared (FTIR) and UV/Visible. The OM and SEM images showed that the AgNPs were well diffused inside the polymer blend with some weak aggregations. The optical properties were enhanced after doping. The NCs films absorbed UV-ray at (λ=220 nm). The indirect energy gap decreased after loading from 3.80 to 3.10 eV but the direct energy gap decreased from 4.25 to 3.75 eV. The AC electrical properties were studied in the frequency range between 100 Hz to 5 MHz. The dielectric constant and loss of NC films were decreased with the increase of AgNPs, while the electrical conductivity increased. The inhibition zone diameters of Escherichia coli bacteria increased with the increasing of AgNPs contents.

The importance of this research is to study the effect of changing the temperature at the same time on each of the prepared samples and during the gas sensing processes, the effects of substrate temperature T_s were investigated after precipitation by the microstructural and optical characteristics of cadmium sulfide using thermal spraying method with different temperatures of (300, 400, and 500) ℃. The structural investigations of these films were studied, showing that the increases in substrate temperature were shown cubic and hexagonal phases according to ICDD card no. (21-0929) and (43-0989). The dramatic change occurred at 500 ℃ in changing the phase from hexagonal to a cubic structure. XRD exhibits a dominant plane at (200) for different substrate temperatures. Optical transmittance, absorption coefficient, and energy gap values were calculated by UV/VIS spectrophotometer. These results showed that the band gap values decreased with increasing substrate temperature. The gas sensitivity was tested for NO₂ gas at several working temperatures from 175 ℃ to 250 ℃, and various gas concentrations from 150 ppm to 200 ppm and found that the sensitivity increase with increasing both the operating temperature and gas concentration for a T_s at 500 ℃ which offer also the best crystallization the best sensitivity at an operating temperature of 175 ℃ is 75% at a gas concentration of 150 ppm.

The effect of manganese doped cobalt oxide (Co₃O₄:Mn) was investigated by two different ratios (1% and 3%), which were precipitated by spray pyrolysis technique (SPT), and was adopted using a laboratory designed glass atomizer. Glass substrates were used to deposit films on them, heated at a temperature of 420 ℃. The structural properties were studied through X-ray diffraction. The results showed that all deposit nanostructured films were polycrystalline and there was a decrease in the preferred reflection intensity along (311) plane resulting in a decrease in the crystallite size. Surface properties were analyzed through atomic force microscopy (AFM), which showed a decrease in the roughness and the particle size growth was a vertical columnar rod. The optical characterization displayed that the transmittance of pure Co₃O₄ nanostructured films was 48% and decreased to 35% for 1% of the Mn concentration, and continued to decrease to 33% with the increase of manganese concentration up to 3%. Optical energy bandgap of pure Co₃O₄ nanostructured films was 1.435 eV and decreased to 1.419 eV for 1% of Mn concentration, and continued to decrease to 1.367 eV with the increase of Mn concentration up to 3%. The highest percentage sensitivity was for the sample doped with 3% Mn, which was about 65%, for NO₂ gas concentration of 600 ppm, at an operating temperature of 200 ℃.

In this work, zinc oxide (ZnO) and Al-doped ZnO (0.002, 0.004, and 0.006 wt.%) thin films were prepared by thermal evaporation technique with the thickness of about 125 nm. The X-ray diffraction (XRD) results showed that the prepared films were crystalline with a hexagonal wurtzite structure and preferential orientation in the (002) direction. The crystallite size increased with the increasing of Al doping. Atomic force microscopy (AFM) confirmed that the films grown by this technique had a good homogeneous surface. The roughness average, root mean square value, and the average grain diameter increased with the increasing of Al doping. The optical properties results showed that the transmittance increased with the increasing of Al doping, while the absorbance decreased. The pure and Al-doped ZnO thin films allowed direct energy gap (E_g) that was increased from 3.50 to 3.80 eV with the increasing of Al doping. The electrical properties of the films were studied, and it was found that all the prepared thin films were n-type and the mobility (μ) decreased with the increasing of Al doping. Current–voltage (I-V) characteristics showed that the highest efficiency was 3.64% with V_oc as of 2.8 V, I_sc as of 3.5 mA/cm² and F.F of 0.371 at the intensity of P =100 mW/cm²..