Water contamination by Acid Orange 7 (AO7), a widely used anionic azo dye in the textile industry, represents a major environmental concern due to its persistence and potential to generate toxic aromatic amines. Herein, we report the synthesis of a novel organobentonite (BPA6) via intercalation of phenylphosphonic acid into bentonite, an organoclay previously unexplored for pollutant removal. XRD analysis revealed an expansion of the basal spacing from 10 to 15.4 Å with an intercalation rate of 86%, while FTIR and SEM confirmed structural reorganization and successful incorporation of phenylphosphonic functional groups. The modification increased interlayer accessibility and introduced additional P–OH active sites, enhancing hydrogen-bond donor density. Consequently, BPA6 achieved a maximum adsorption capacity of 123.3 mg.g⁻¹ at 55 °C, significantly exceeding raw bentonite. The kinetics were well described by the pseudo-second-order model, while the equilibrium data fit best with the Langmuir–Freundlich model. Thermodynamic analysis indicated a predominantly physisorption-driven process. BPA6 maintained stable performance over multiple regeneration cycles. Mechanistic insight was obtained by correlating spectroscopic, adsorption, and thermodynamic data, revealing a clear relationship between structure, surface chemistry, interactions, and performance. The adsorption mechanism is primarily governed by hydrogen bonding between Si–OH and intercalated P–OH moieties and the sulfonate and amine moieties of AO7. Phenylphosphonic acid intercalation optimizes clay surface chemistry, enhancing dye adsorption by BPA6 and highlighting its potential as a sustainable, high-performance wastewater adsorbent. Copyright © 2026 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Currently, new technologies are widely used in the context of the development of the information society, secondary and higher education. The use of digital tools, STEM resources, 3D modeling programs and 3D printing equipment, laboratory stands made with their own hands has been widely used in the educational process. All these conditions are aimed at preparing future specialists to meet the requirements of the XXI century. Physics as a fundamental science is one of the fundamental disciplines in the field of STEM. Therefore, the use of STEM elements in teaching physics has a huge impact on the development of the activities of future specialists in the engineering and technical field. Especially STEM products and laboratory stands, developed by students in conjunction with the teacher's guidance, increase the effectiveness of the educational process. This will make it possible to create creative products and thereby develop the scientific and technical industry of the country. The purpose of this study is to implement physics education in universities on the basis of interdisciplinary connections through mini-projects and the development of educational and research stands and to determine the features of their implementation in the educational process. The research used methods of systematic analysis of articles published in highly rated journals, 3D modeling and printing methods, as well as constructive research methods. In addition, qualitative research methods were used in the pedagogical process. The results of the study showed that the development of laboratory stands for the implementation of mini-projects, thereby developing the creativity of students, is of great importance. It became known that students are actively involved in engineering, are interested in this area and increase their knowledge level when performing mini-projects. The results of the study will allow new areas of research to appear in the future, improve the methodology of teaching physics at universities, combine knowledge with science and industry.

In this study, a fully coupled three-dimensional multiphysics CFD model of a photoelectrochemical (PEC) water splitting cell incorporating a ZnO/BiVO₄ photoanode was developed using COMSOL Multiphysics^® 6.1. The model integrates semiconductor charge transport, ionic transport (diffusion, migration, and convection), electrochemical kinetics, and fluid dynamics within a widely adopted experimental configuration. This work focuses on coupling the dominant transport phenomena governing macro-scale PEC behavior under realistic operating conditions, allowing the overall PEC behavior to be captured without resolving microscopic interfacial complexities. The simulation results show good agreement with previously reported experimental data in terms of photocurrent density, demonstrating the capability of the model to reproduce photocurrent behavior. The developed framework provides insight into the interplay between photogenerated charge transport and electrochemical reactions and can serve as a predictive tool for analyzing and optimizing PEC system performance prior to experimental implementation.

Al-Cu-Fe quasicrystalline coatings were deposited on AISI 321 stainless steel substrates by high-velocity oxy-fuel (HVOF) spraying at oxygen pressures of 3.0, 3.5, and 4.0 bar. The influence of oxygen pressure on the phase composition, microstructure, porosity, corrosion behavior, thermal stability, and microhardness of the coatings was investigated using X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM/EDS), ImageJ porosity analysis, electrochemical corrosion testing in 3.5 wt.% NaCl solution, simultaneous thermal analysis (TGA/DSC), and microhardness measurements. XRD analysis revealed the formation of quasicrystalline-related intermetallic phases together with Al, Fe₃Al₁₃, FeAl, Fe₃O₄, CuFe₂O₄, Cu₂O, and CuO phases. The coating deposited at 3.5 bar exhibited the lowest porosity (5.37%), the most homogeneous microstructure, and the largest residual coating thickness after corrosion testing. SEM and EDS analyses indicated that corrosion preferentially initiated at pores, splat boundaries, and phase interfaces, while the coating produced at 3.5 bar demonstrated the most stable surface condition after exposure to a 3.5 wt.% NaCl solution. Thermal analysis showed that all coatings remained stable up to 900 °C. Sample (a) exhibited the lowest mass loss and the highest thermal stability, whereas sample (b) demonstrated the most favorable combination of structural integrity, phase ordering, coating density, corrosion-related performance, and thermal stability. Microhardness values of the coatings ranged from 754 to 778 HV, significantly exceeding that of the AISI 321 substrate. The results demonstrate that oxygen pressure is a critical parameter controlling the microstructure and functional properties of HVOF-sprayed Al-Cu-Fe coatings, with 3.5 bar providing the most balanced set of properties.

With the growth of the global population and expansion of the world economy, the global demand for energy continues to rise steadily. Most of the produced energy still relies on fossil fuels, which leads to the depletion of natural resources and environmental degradation. This situation drives active research and development in renewable energy technologies. One of the most promising directions is the electrocatalytic production of hydrogen from water, considered an efficient solution to the intermittency of renewable energy generation. The process of water electrolysis includes two half-reactions: the anodic oxygen evolution reaction (OER, 4OH− → O2 + 2H2O + 4e−) and the cathodic hydrogen evolution reaction (HER, 2H2O + 2e− → H2 + 2OH−). Under standard conditions, the equilibrium potential of water electrolysis is 1.23 V, but in practice it reaches 1.6–2.0 V due to significant charge transfer losses in the OER process. Therefore, the development of efficient and stable electrocatalysts is key for large-scale hydrogen and oxygen production, reducing energy consumption, and advancing industrial water electrolysis technologies. Among various materials, perovskite-type oxides (ABO3) are of particular interest due to their natural abundance, high chemical stability, and tunable composition. These properties make them promising high-activity catalysts for the oxygen evolution reaction. However, their practical application is limited by relatively low specific surface area, which leads to reduced catalytic activity. Keywords: Perovskite, hydrogen, photocatalysts, water splitting, renewable energy, overpotential, activity, electrochemistry.