Thin films of zinc oxide (ZnO) doped with transition metals have recently gained significant attention due to their potential applications in a wide range of optoelectronic devices. This study focuses on ZnO thin films doped with the transition metals Co, Fe, and Zr, exploring various aspects of their structural, morphological, optical, electrical, and photoluminescence properties. The thin films were produced using RF and DC co-sputtering techniques. The X-ray diffraction (XRD) analysis revealed that all the doped ZnO thin films exhibited a stable wurtzite crystal structure, showcasing a higher structural stability compared to the undoped ZnO, while the atomic force microscopy (AFM) imaging highlighted a distinctive granular arrangement. Energy-dispersive X-ray spectroscopy was employed to confirm the presence of transition metals in the thin films, and Fourier-transform infrared spectroscopy (FTIR) was utilized to investigate the presence of chemical bonding. The optical characterizations indicated that doping induced changes in the optical properties of the thin films. Specifically, the doped ZnO thin film’s bandgap experienced a significant reduction, decreasing from 3.34 to 3.30 eV. The photoluminescence (PL) analysis revealed distinguishable emission peaks within the optical spectrum, attributed to electronic transitions occurring between different bands or between a band and an impurity. Furthermore, the introduction of these transition metals resulted in decreased resistivity and increased conductivity, indicating their positive influence on the electrical conductivity of the thin films. This suggests potential applications in solar cells and light-emitting devices.

The increasing demand for energy and electricity and the depletion of fossil fuels are global problems. In recent years, dye-sensitized solar cell (DSSC) technologies have gained notoriety for their application in solar energy. DSSCs are considered a promising alternative renewable energy source to both inorganic and organic photovoltaic (PV) cells. Many types of dyes are being investigated to enhance the light-harvesting properties of DSSCs, but the actual realization of these absorbers in cell structure requires optimum parameters. The main aim of this study was to simulate proposed zinc phthalocyanine (ZnPC)-based structures to validate their design, assess their performance for commercial implementation, and optimize the cell parameters for optimum efficiency. To that end, Scaps-1D was employed to evaluate the performance of DSSCs to determine their optimum parameters. We found that ZnPC and isopropoxy ZnPC molecules outperform others molecules because of better optoelectronic properties. Several other parametric effects, such as photoactive layer thicknesses, doping densities, trap densities, and charge carrier mobilities, were also evaluated to observe their impact on device performance. The results show that moderate thickness, low defect density, moderate doping, and charge carrier mobility are favorable for better device performance due to low recombination losses, electrical losses, and better transport of charge carriers. The utmost power conversion efficiency values found for ZnPC- and ZnPC: PC70BM-based DSSCs after optimization were 9.50% and 9.81%. This paper also suggests a practical method for efficiently using DSSC cells by modifying factors that are significantly reliant on DSSC performance and output.

The electrospinning process allows the production of nanofibers from polymer solutions, making them suitable for various applications such as sensors, electronic devices, conductive materials, and advanced composites for high-temperature environments. In this research, polyaniline (PANI) was doped with camphor sulfonic camphor sulfonic acid (HCSA). HCSA dopant is used to modify the electrical and structural properties of polyaniline. To introduce reduced graphene oxide as a nanofiller to enhance the electrical properties of the polymer. Both the HCSA-doped PANI and HCSA-doped PANI with rGO nanofibers were electro-spun separately to create individual nanofibers. Fourier-transform infrared spectroscopy was used to investigate the chemical composition and functional groups present in the nanofibers. Field emission scanning electron microscopy was employed to study the nanofibers’ morphology, structure, and surface characteristics. Thermogravimetric analysis was used to assess the thermal stability of the nanofibers and to approximate the content of rGO. These results indicate that the addition of reduced graphene oxide (rGO) led to improvements in the nanofibers’ electrical conductivity and thermal stability.

The study intended to enhance the visible light activity of titanium dioxide (TiO₂) by doping it with carbon, thereby reducing its effective band gap. Carbon-doped TiO₂ nanofibers were synthesized using a simple electrospinning process. The prepared samples were then characterized to investigate their properties. X-ray diffraction (XRD) analysis confirmed the presence of the rutile phase of TiO₂ in the nanofibers. The XRD pattern exhibited maximum peak intensity at the highest temperature used during synthesis, indicating that the temperature influenced the crystalline structure of the nanofibers. Scanning electron microscopy (SEM) was conducted to examine the morphology of the nanofibers. The results revealed that as temperature increased, the diameter of the nanofibers decreased. The XRF (X-ray Fluorescence) results indicate the atomic composition of carbon-doped TiO₂ nanofibers. UV–vis spectroscopy was performed to evaluate the optical properties of the carbon-doped TiO₂ nanofibers. The results demonstrated a shift of the optical band towards the visible region. Moreover, the carbon doping reduced the effective band gap, resulting in improved visible light activity of the TiO₂ material. These results have significant implications for potential applications of carbon-doped TiO₂ nanofibers in various fields, such as photocatalysis and solar energy conversion.