In this study, a hybrid organic–inorganic perovskite solar cell (PSC) based on methylammonium germanium triiodide (MAGeI₃), which is composed of methylammonium ($\mathrm{C}{\mathrm{H}}_3\mathrm{N}{\mathrm{H}}_3^{+})$ cations and germanium triiodide ($\mathrm{G}\mathrm{e}{\mathrm{I}}_3^{-}$) anions, has been numerically studied using SCAPS-1d codes. An extensive investigation of various electron transport layers (ETLs) and hole transport layers (HTLs) was conducted to identify the most optimal device configuration. The FTO/ZnOS/MAGeI₃/PEDOT-WO₃ structure performed the highest efficiency of all combinations tested, with an impressive optimized efficiency of 15.84%. This configuration exhibited a V_oc of 1.38 V, J_sc of 13.79 mA/cm², and FF of 82.58%. J-V characteristics and external quantum efficiency (EQE) measurements indicate that this device offers superior performance, as it has reduced current leakage, improved electron and hole extraction characteristics, and reduced trap-assisted interfacial recombination. Optimum device performance was achieved at active layer thickness of 560 nm. These findings may also serve as a basis for developing lightweight and ultra-thin solar cells, in addition to improving overall efficiency. Furthermore, a comprehensive correlation study was conducted to evaluate the optimum thickness and doping level for both ZnOS-ETL and PEDOT-WO₃-HTL. The photovoltaic performance parameters of the FTO/ZnOS/MAGeI₃/PEDOT-WO₃ structure were analyzed over a wide temperature range (275 K to 450 K). The structure exhibited stable performance at elevated operating temperatures up to 385 K, with only minimal degradation in PCE of approximately 0.42%. Our study underscores the promise of utilizing cost-effective and long-term stability materials like ZnOS and PEDOT-WO₃ alongside the toxic-free MAGeI₃ perovskite. This combination exhibits significant potential for eco-friendly PSC, paving the way for the development of highly efficient ultra-thin PSC.

A contrast agent with specific characteristics is essential for high-quality magnetic resonance imaging (MRI). It plays a crucial role in enhancing the visibility of certain tissues and structures, making it imperative for diagnostic procedures. Superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as a promising alternative to traditional contrast agents for MRI due to their non-toxicity and superior magnetic properties. However, a suitable surface coating strategy is needed to produce polymer-coated SPIONs with controllable sizes in order to enhance their stability and biocompatibility. This study presents a novel one-pot synthesis method for the production of highly stable polyvinylpyrrolidone (PVP)-coated SPIONs. By systematically manipulating the physicochemical properties of SPIONs, the effect of different molecular weights of PVP was studied. The results showed that SPIONs coated with PVP with molecular wight 40,000 g/mol (40 K) exhibited a high magnetization (Ms = 48.4 emu/g), an average size distribution (11.61 nm), and excellent stability. The relaxivity of coated and uncoated SPIONs was investigated using MRI images. The results revealed that the (r₂/r₁) ratio of PVP40K-SPIONs was 72.55, compared to 55.72 for the bare SPIONs, making them a highly promising T₂-contrast agent for future development of MRI applications. This study opens new avenues for the development of biocompatible and stable SPIONs for improved medical diagnostic and imaging.

In this study, laser-assisted chemical bath synthesis (LACBS) was used to prepare pure and Ag-doped ZnO submicron structures using a simplified hydrothermal approach that did not require a catalyst. The photocatalytic degradation of Methylene Blue was investigated under blue laser irradiation (λ = 444.5 nm and I = 8000 lx). The doping concentration varied (2%, 4%, 6%, 8%, tando 10%) and was prepared by LACBS using a continuous blue laser (P = 7 W, λ = 444.5 nm) for the first time. XRD, FE-SEM, EDX, and UV-Vis investigated the characteristics of the samples produced by the LACBS. ZnO: Ag_(10%) submicron flowers are essential in rapid photodegradation under blue laser irradiation. The high surface area and catalytic activity of the prepared Ag-decorated ZnO are attributed to this improved photocatalytic activity. Using UV-visible spectroscopy, the photocatalytic efficiency was determined from the absorption spectra. The separation of photo-generated electron-hole pairs was facilitated, and the absorption edge of the hybrid submicron structures shifted into the visible spectrum region due to a combination of the Ag plasmonic effect and surface imperfections in ZnO. Effective visible light absorption was achieved via band-edge tuning, which increased the ZnO:Ag submicron structures’ ability to degrade dyes.

Antimicrobial resistance poses a significant threat to global health, amplified by factors such as water scarcity and suboptimal hygienic practices. Addressing AMR effectively necessitates a comprehensive strategy encompassing enhanced access to potable water, developing innovative antibiotics, and exploring alternative treatment modalities, such as harnessing solar photocatalysis with zinc oxide nanoparticles for water purification and antimicrobial applications. The Laser-Assisted Chemical Bath Synthesis (LACBS) technique facilitates the fabrication of pure ZnO nanostructures, providing a potentially efficacious solution for mitigating pathogen proliferation and managing wastewater. The photocatalytic degradation of MB and MO dyes was investigated using blue laser light at 445 nm, and degradation rates were determined accordingly. Ag-doped ZnO nanostructures were characterized through X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. The antimicrobial efficacy of LACBS-synthesized ZnO nanoparticles was assessed against C. albicans, S. aureus, B. subtilis, E. coli, and K. pneumoniae using the disc diffusion method, revealing 40 mm, 37 mm, 21 mm, 27 mm, and 45 mm inhibition zones at the highest concentration of doped-Ag (4.5%), respectively. These inhibition zones were measured in accordance with the guidelines established by the Clinical and Laboratory Standards Institute. X-ray diffraction patterns for ZnO, ZnOAg_(1.5%), ZnO:Ag_(3%), and ZnO:Ag_(4.5%) samples revealed variations in intensity and crystallinity. Scanning electron microscopy exposed morphological disparities among the nanostructures, while energy-dispersive X-ray spectroscopy verified their elemental compositions. UV-Vis absorption analyses inspected the optical band gaps, and Fourier-transform infrared spectra identified the stretching mode of metal-oxygen bonds. Under blue laser irradiation, Ag-doped ZnO exhibited enhanced photocatalytic activity during the photocatalytic degradation. These nanoparticles, synthesized via the cost-effective and straightforward LACBS method, benefit from silver doping that augments their electron-trapping properties and photocatalytic activity, thereby enabling efficient dye degradation. Consequently, Ag-doped ZnO nanoparticles hold promise as a potent solution for counteracting drug-resistant microorganisms and as an effective disinfectant.

Background: Achieved Silica Nanoparticles (SiNPs) to encapsulate the photosensitizer [Protoporphyrin IX (PpIX)] in photodynamic therapy (PDT) application was reported in this research. Materials and Methods: Cytotoxicity for five different concentrations of encapsulated and naked PpIX was measured. Optimum concentration and optimum exposure time of encapsulated and naked PpIX that needed to destroy the cells (Osteosarcoma cells) was measured. Results: The results showed that the encapsulated PpIX has more efficacy compared to the naked PpIX and the applicability of the encapsulated PpIX-SiNPs was proved on osteosarcoma cells. Conclusion: The results established the important in-vitro photodynamic effectiveness of PpIX-SiNP, which may open a new application for PpIX in its clinical and in-vitro studies.