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We demonstrate how the formation of octahedral microcrystals of arsenic oxide As2O3 in the form of arsenolite with a size of 200 nm to 10 μm can be initiated by the electrochemical etching method with simultaneous deposition on the surface of substrates with n-GaAs (111). Crystallites were formed on a previously synthesized porous layer of GaAs. To explain the behavior of formation on the surface of the monocrystalline GaAs porous layer and As2O3 crystallites in the electrochemical reaction, we propose a qualitative model based on the decomposition of binary semiconductors in contact with electrolytes. Under this model, the crystallization of precipitated oxides occurs as a result of the transfer of ions to the crystal surface as a result of the electrolysis process. The formation of the composite structure takes place on the surface of the semiconductor and is characterized by the minimization of elastic energy. XRD analysis showed the formation of a complex compound of As2O3 and As0.172Sb0.570O1.113. The appearance of antimony is explained in terms of the formation of new centers when the As atom is replaced by an Sb doping atom in the crystal. Directed controlled oxidation technologies make it possible to synthesize a reliable passivating layer consisting of one type of oxide, namely As2O3 in the cubic phase of arsenolite. In addition, such structures can be used in photonics devices and as photocatalysts.

This study presents the experience of managing Berdyansk State Pedagogical University in the first year of a full-scale war. The purpose is to analyze the impact of management decisions on the performance indicators of the university in the conditions of temporary occupation and relocation to a new place. The relocation of Berdyansk State Pedagogical University (BSPU) to a safer territory enabled the resumption of educational activities in May 2022, after 53 days of functioning under occupation by russian troops. University staff decreased by 13%, with 57% moving to Ukraine-controlled territories and 43% remaining in the occupied zone. In addition, the student contingent decreased by 15%. The university’s scientific activity during the war decreased for only 9% in publication activity, and funding for science in 2023 increased by 379% compared to 2021. The university continued its third mission of social cooperation by providing humanitarian and psychological assistance and documenting the testimonies of people affected by the occupation. The university community currently exists in a virtual format, with staff and students in different parts of Ukraine and the world. The university must look to the future and overcome existing problems, such as preserving academic potential and student contingent, restoring electronic systems, and continuing pedagogical education. AcknowledgmentThis study was funded by the Ministry of Education and Science of Ukraine (grants 0121U10942 and 0123U100110).We are grateful to the Armed Forces of Ukraine for providing the security necessary to conduct this analysis. This work would not have been possible without the perseverance and courage of the Ukrainian army.We also thank the entire team of Berdyansk State Pedagogical University. Thanks to your perseverance, resilience, and unity, the university continues to operate for the development of Ukraine.

CdxTeyOz/CdS/ZnO heterostructures were obtained by the SILAR method using ionic electrolytes. A CdS film was formed as a buffer layer for better adhesion of the cadmium-tellurium oxides to the substrate surface. In turn, the ZnO substrate was previously prepared by electrochemical etching to form a rough textured surface. In addition, an annealing mode was used in an oxygen stream to complete the oxidation process of the heterostructure surface. The resulting nanocomposite was investigated using RAMAN, XRD, SEM, and EDX methods. We assume that the oxides CdO and TeO4 initially form on the surface and later evolve into TeO2 and TeO3 when saturated with oxygen. These oxides, in turn, are the components of the ternary oxides CdTeO3 and CdTe3O8. It should be noted that this mechanism has not been fully studied and requires further research. However, the results presented in this article make it possible to systematize the data and experimental observations regarding the formation of cadmium-tellurium films.

We study the directed oxidation processes of the n-GaAs surface as a result of the electrochemical treatment of a semiconductor in an aqueous-alcoholic solution of hydrochloric acid. The analysis of the voltampere characteristics was carried out in order to study the process kinetics, this made it possible to establish the formation stages of the oxide film and islands. The surface morphology was estimated according to the area characteristics, linear sizes, Solidity and Round islands. It was shown that the oxidation occurs by the Stranski-Krastanov mechanism. The formation study of own oxides on the GaAs surface is extremely important, because oxides can significantly impact the material properties. The native oxides of semiconductors are an inactive film that reliably protects the surface from environmental action and when interacting with aggressive substances. In addition, the native oxides of GaAs exhibit semiconductor properties that allow to create oxide/GaAs heterostructures with heterojunctions for optoelectronic applications.