In this article, the synthesis, optical, and electrical properties of composites consisting of polyethylene oxide (PEO), carboxymethyl cellulose (CMC), and titanium dioxide nanoparticles are examined. Flexible nanocomposite samples comprising PEO, CMC, and TiO₂ nanoparticles were produced swiftly via using the cast synthesis method. In addition, XRD and FT-IR analysis were performed in order to analyze the structures of the prepared samples. Our results demonstrate the PEO/CMC blend’s effectiveness in interacting with TiO₂ nanoparticles. The optical properties of the PEO/CMC and nanocomposite samples, such as the energy band gap, were studied using the UV/Vis optical absorbance. It was found that as TiO₂ NP weight fraction increases, the energy gap narrows. Moreover, TiO₂ nanoparticles with an average size of 16 nm were formed in spherical and rod shapes, according to a TEM image. The SEM images demonstrate how the distribution of TiO₂ NPs increased upon the surfaces of the prepared films. The antibacterial activity in the nanocomposites was shown to be enhanced by the TiO₂ NP concentrations. Finally, we proposed that PEO/CMC-0.8 wt. % TiO₂ nanocomposites with enhanced optical, electrical, and dielectric properties should be used in electrochemical devices.

This research examined the production of a V₂O₅-g-C₃N₄ nanocomposite to remove organic dyes from wastewater. To generate the V₂O₅-g-C₃N₄ nanocomposite, the sonication method was applied. The testing of V₂O₅-g-C₃N₄ with various dyes (basic fuchsin (BF), malachite green (MG), crystal violet (CV), Congo red (CR), and methyl orange (MO)) revealed that the nanocomposite has a high adsorption ability towards BF, MG, CV, and CR dyes in comparison with MO dye. It was established that the modification of pH influenced the removal of CV by the V₂O₅-g-C₃N₄ nanocomposite and that under optimal operating conditions, efficiency of 664.65 mg g⁻¹ could be attained. The best models for CV adsorption onto the V₂O₅-g-C₃N₄ nanocomposite were found to be those based on pseudo-second-order adsorption kinetics and the Langmuir isotherm. According to the FTIR analysis results, the CV adsorption mechanism was connected to π–π interactions and the hydrogen bond.

Throughout this research, a unique optical sensor for detecting one of the most dangerous heavy metal ions, Cu(II), was designed and developed. The (4-mercaptophenyl) iminomethylphenyl naphthalenyl carbamate (MNC) sensor probe was effectively prepared. The Schiff base of the sensor shows a “turn-off” state with excellent sensitivity to Cu(II) ions. This innovative fluorescent chemosensor possesses distinctive optical features with a substantial Stocks shift (about 114 nm). In addition, MNC has remarkable selectivity for Cu(II) relative to other cations. Density functional theory (DFT) and the time-dependent DFT (TDDFT) theoretical calculations were performed to examine Cu(II) chelation structures and associated electronic properties in solution, and the results indicate that the luminescence quenching in this complex is due to ICT. Chelation-quenched fluorescence is responsible for the internal charge transfer (ICT)-based selectivity of the MNC sensing molecule for Cu(II) ions. In a 1:9 (v/v) DMSO-HEPES buffer (20 mM, pH = 7.4) solution, Fluorescence and UV-Vis absorption of the MNC probe and Cu(II) ions were investigated. By utilizing a solution containing several metal ions, the interference of other metal ions was studied. This MNC molecule has outstanding selectivity and sensitivity, as well as a low LOD (1.45 nM). Consequently, these distinctive properties enable it to find the copper metal ions across an actual narrow dynamic range (0–1.2 M Cu(II)). The reversibility of the sensor was obtained by employing an EDTA as a powerful chelating agent.

This study investigated the photocatalytic degradation of RB dye by V₂O₅@g-C₃N₄ nano-catalysts. The sonication method was utilized to create V₂O₅@g-C₃N₄ nano-catalysts. V₂O₅@g-C₃N₄ nano-catalysts were characterized using X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), high-resolution electron microscopy (TEM), BET-surface area analyzer, X-ray photoelectron spectroscopy (XPS), and ultraviolet spectroscopy. In the meantime, the photocatalytic activity, pH, and photocatalyst dosage are investigated in depth to account for RB dye decolorization. The rate constant for RB dye photodegradation was 0.0517 (min⁻¹) and the decolorization rate was 93.4%. The degrading efficiency of RB dye by V₂O₅@g-C₃N₄ nanocatalysts is consistent with pseudo-first-order kinetics. The results of this study demonstrated that V₂O₅@g-C₃N₄ nanocatalysts are particularly effective at destroying dyes in water.

Cleaning contaminated water under light with a novel type of heterogeneous photocatalysts is regarded as a critical method for wastewater resolution. Thus, a unique mesoporous Ru-ZnO@g-C₃N₄ nanocomposite with an increased surface area was synthesized through the ultrasonic technique in the presence of methanol. The X-ray diffraction pattern efficiently validated the crystal structure of the Ru-ZnO hybrid and allowed it to be integrated into the g-C₃N₄ structure. TEM imaging revealed the Ru-ZnO nanocomposite as spherical particles spread uniformly throughout the g-C₃N₄ nanosheet. X-ray photoelectron spectroscopy (XPS) was applied to determine the bonding properties of the samples. Under visible illumination, the synthesized nanocomposites of Ru-ZnO@g-C₃N₄ were evaluated as a new effective photocatalyst for degrading organic pigments in aquatic conditions.