Ultrasonically cleaned glass slides are used as substrates for receiving the different thickness of Zinc selenide (ZnSe) films. The deposition processes of our investigated films were done at room temperature using physical thermal evaporation mechanism under vacuum ≈2 × 10⁵ mbar. We investigated the optical and structural parameters of ZnSe thin films in correlation with film thickness (200–650 nm). Various techniques such as UV–vis-NIR spectrophotometer, x-ray diffraction lines and field emission scanning electron microscope were used to investigate aforementioned parameters. Structural analysis indicate that the films exhibited cubic preferred orientation along the plane (111) and the crystallinity and crystallite size of films increases linearly with film thickness. The optical band gap ranges from 2.69 to 2.81 eV and it is founded that it increases with film thickness. According to the applied Swanepoel’s approach, it is possible to estimate the optical parameters and average thickness of the ZnSe thin films of different thicknesses with higher accuracy.

This research focuses on the synthesis of a new composite material, As₂O₃-poly(1H-pyrrole) (P1HP), for the generation of hydrogen gas. The novelty lies in the utilization of eco-friendly and cost-effective seawater as the source of hydrogen gas. The study aims to develop a sustainable and efficient approach for hydrogen production using this novel composite material and seawater as the raw materials. The As₂O₃/P1HP nanocomposite is synthesized through the polymerization of 1H-pyrrole. The crystal structure and size of the nanocomposite are determined using XRD analysis, which indicates a lattice constant of 11.06 Å and a crystallite size of 4.03 nm via the Scherer equation. The surface topography is visualized using SEM and TEM, revealing the presence of both large agglomerate particles and very small particles with a size of approximately 21 nm. The nanocomposite exhibits excellent optical absorption behavior and a small bandgap of 1.73 eV, making it suitable for hydrogen generation using Red Sea water as an electrolyte. The hydrogen production rate is measured to be 21 μmole cm⁻¹.h, while the current density (J_ph) values with and without incidence light are −0.24 and −0.05 mA.cm⁻², respectively. The J_ph values increase from −0.09 to −0.15 mA.cm⁻² as the incidence photon wavelengths increase from 440 to 730 nm, indicating an enhancement in the rate of hydrogen generation. The use of low-cost materials and a natural source of electrolyte make this approach a promising candidate for renewable energy production and hydrogen gas generation.

The doped-CdO nanostructures with transition metals attract considerable interest due to their chemical and physical properties. That differs from those bulk materials, especially the variation of their optical bandgap, which makes them used in various applications. This communication focuses on the synthesis and characteristic properties of un-doped/doped Cd_1-x Cu _x O nanocomposites produced by the co-precipitated technique. XRD patterns indicate the polycrystalline nature of the investigated samples whereas Cu atoms have been effectively diffused into the Cd sites. It is found that at lower concentrations of Cu (111) diffraction planes were mainly the preferential ones while at higher concentrations, the plane (200) appeared as a preferential one. The average particle size increases with the addition of Cu dopant. From TEM it is found that the average particle size ranges from ∼18 to 89 nm. SEM photographs show a formation of distinguished agglomerates. Also, EDX shows that the common elements (Cd, Cu, and O) were obtained without any impurities. The thermal stability increases with increasing Cu concentrations. The optical band gap (E _g) decreases and Urbach energy (E _u) increases, respectively, with increasing the content of Cu. As a result, the CdO doped Cu can be used to develop novel photovoltaic and light-emitting instruments.