In this work, magnetic nanoparticles based on magnetite were successfully prepared via rapid microwave-assisted synthesis. In order to obtain the ternary core–shell Fe₃O₄/SiO₂/TiO₂ nanocomposite, first magnetite (Fe₃O₄) nanoparticles were coated with a protective layer of silica (SiO₂) and finally with titania (TiO₂). The composite configuration comprising porous and photoactive shells should facilitate the removal of organic micropollutants (OMPs) from water. Furthermore, the magnetic core is critical for processing the management of the photocatalytic powder suspension. The magnetization of the prepared magnetic nanoparticles was confirmed by vibrating-sample magnetometry (VSM), while the structure and morphology of the core–shell nanocomposite were investigated by means of XRD, FTIR, and SEM. Adsorption and photocatalysis were evaluated by investigating the removal efficiency of ciprofloxacin (CIP) as a model OMP using the prepared magnetic core–shell nanocomposite under UV-A light irradiation. It was found that the Fe₃O₄/SiO₂/TiO₂ nanocomposite showed good synergistic adsorption and photocatalytic properties. The measurement of iron in eluate confirmed that no leaching occurred during the photocatalytic examination. The recovery of magnetic nanocomposite by an external magnetic field confirmed that the magnetically separated catalyst is highly suitable for recycling and reuse.

Nitrogen-doped TiO₂ (N/TiO₂) photocatalyst nanoparticles were derived by the environmentally friendly and cost-effective microwave-assisted synthesis method. The samples were prepared at different reaction parameters (temperature and time) and precursor ratio (amount of nitrogen source; urea). The obtained materials were characterized by X-ray diffraction (XRD), photoelectron spectroscopy (XPS), Raman spectroscopy (RS), infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), electron microscopy (SEM-EDS), and nitrogen adsorption/desorption isotherms. Two cycles of optimizations were conducted to determine the best reaction temperature and time, as well as N content. The phase composition for all N/TiO₂ nanomaterials was identified as photoactive anatase. The reaction temperature was found to be the most relevant parameter for the course of the structural evolution of the samples. The nitrogen content was the least relevant for the development of the particle morphology, but it was important for photocatalytic performance. The photocatalytic activity of N/TiO₂ nanoparticle aqueous suspensions was evaluated by the degradation of antibiotic ciprofloxacin (CIP) under different irradiation spectra: ultraviolet A light (UVA), simulated solar light, and visible light. As expected, all prepared samples demonstrated efficient CIP degradation. For all irradiation sources, increasing synthesis temperature and increasing nitrogen content further improved the degradation efficiencies.

The unique properties of nanostructures, such as their high surface-to-volume ratio, tunable physical and chemical characteristics, and enhanced sensitivity, are critical for advancing gas detection technologies. Therefore, this comprehensive review explores the recent advancements in nanostructured materials, emphasizing their pivotal role in enhancing gas sensing performance. A key focus of this review is metal oxide-based gas sensors, and the impact of synthesis methods and (micro)structural properties on sensor performance is thoroughly examined. By segmenting the discussion into 1D nanostructured materials, including different metal oxides, the review provides a broad yet detailed perspective on how different functional materials contribute to gas sensing efficiency. From a performance standpoint, this review highlights critical sensing parameters, including gas detection mechanisms, response times, selectivity, stability, and operating conditions. High-end detection values may reach around a few ppb for most gases. Beyond evaluating current advancements, this review also addresses existing challenges and future research directions, particularly in scalability, long-term sensor stability, low-temperature operation, and integration into real-world applications. By providing a comprehensive and up-to-date analysis, this review serves as a valuable resource for researchers and engineers, offering insights that can drive the next generation of high-performance, reliable, and selective gas sensors.

Nanocomposites comprising nitrogen-doped TiO₂ and reduced graphene oxide (N/TiO₂/rGO), with different rGO loading qualities, were prepared by a cost-effective microwave-assisted synthesis method. The synthesized materials were broadly characterized by Raman spectroscopy, X-ray diffraction (XRD), infrared spectroscopy (FTIR), photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), electron microscopy (SEM-EDS), and nitrogen adsorption/desorption isotherms. Anatase was the only crystalline phase observed for all synthesized materials. The rGO loading did not affect the morphological properties, but it positively influenced the photocatalytic activity of the nanocomposite materials, especially at low rGO loading. Photocatalysts were evaluated via the degradation of specific organic micropollutant (OMP) pharmaceuticals: ciprofloxacin (CIP), diclofenac (DCF), and salicylic acid (SA), under different radiation sources: ultraviolet A (UVA), solar light simulator (SLS), blue visible light (BVL) and cold visible light (CVL). CIP and SA were removed effectively via the synergy of adsorption and photocatalysis, while DCF degradation was achieved solely by photocatalysis. After implementing scavenger agents, photocatalytic degradation processes mainly depended on the specific pollutant type, while irradiation sources barely defined the photocatalytic mechanism. On the other hand, changes in irradiation intensity significantly influenced the photolysis process, while photocatalysis was slightly affected, indicating that irradiation spectra are more relevant than intensity.

Zirconia ceramics are used in a wide range of applications, including dental restorations, bioimplants, and fuel cells, due to their accessibility, biocompatibility, chemical resistance, and favorable mechanical properties. Following the development of 3D printing technologies, it is possible to rapidly print zirconia-based objects with high precision using stereolithography (SLA) and digital light processing (DLP) techniques. The advantages of these techniques include the ability to print multiple objects simultaneously on the printing platform. To align with the quality standards, it is necessary to focus on optimizing processing factors such as the viscosity of the suspension and particle size, as well as the prevention of particle agglomeration and sedimentation during printing, comprising the choice of a suitable debinding and sintering mode. The presented review provides a detailed overview of the recent trends in preparing routes for zirconium oxide bodies; from preparing the suspension through printing and sintering to characterizing mechanical properties. Additionally, the review offers insight into applications of zirconium-based ceramics.