Subject of study. Solar cells based on CsPbI3 and CsPbBr3 photosensitive inorganic perovskites are investigated. Aim of study. The study aimed to simulate and fabricate inorganic perovskite solar cells based on CsPbI3 and CsPbBr3. Method. A theoretical study was conducted using the open-source AFORS-HET program, which is designed for one-dimensional modeling of solar cells and other optoelectronic devices. During the fabrication of the structures, various equipment, including an EZ4 spin coater for thin film and photoresist deposition, ULAB US-1500D heated laboratory magnetic stirrers, and a vacuum thermal deposition station, was employed. Main results. Solar cells based on CsPbI3 and CsPbBr3 photosensitive inorganic perovskites were simulated using the AFORS-HET software. The primary photovoltaic cell parameters, including the fill factor, short-circuit current, open-circuit voltage, and efficiency, were estimated. A theoretical analysis was performed to identify the factors and defects in the perovskite films affecting the solar cells' performance. Based on the simulation results, photosensitive structures using CsPbI3 were fabricated and characterized. Practical significance. The studied solar cells based on CsPbI3 and CsPbBr3 exhibit potential as efficient solar-to-electrical energy converters. (c) 2025 Optica Publishing Group

The present paper is devoted to the investigation of the formation process and growth of Gd2Ti2O7 nanocrystals with a pyrochlore structure doped with Sm3+ and Nd3+ ions. During the Gd2Ti2O7:Sm3+/Nd3+ nanoparticles synthesis, aqueous solutions of gadolinium, samarium and neodymium nitrates were added to a mixture of titanium isopropoxide, and polyethylene glycol was diluted with isopropyl alcohol, after which the resulting substance was evaporated to a gel state and heat-treated according to a two-stage scheme. As a result of the study, it has been shown that the forming material had a trabecular structure with a developed network of macro- and micropores. The use of a two-stage heat treatment promotes uniform distribution of different nature atoms in resulting samples. In addition it has been concluded that gadolinium titanate crystalls with a pyrochlore structure is formed by an aggregation mechanism at 700 °C from an X-ray amorphous precursor. From the point of view of obtaining a single-phase material, a possibility of varying nanocrystals dimensions and the pyrochlore structure defectiveness, annealing of the precursor in the temperature range of 750–900 °C is most promising. In this case, the most significant percentage of Sm3+ and Nd3+ ions, which change their localization with increasing synthesis temperature, are incorporated into the crystal structure of Gd2Ti2O7. Doping of Gd2Ti2O7 nanocrystals not only leads to appearance of expected photoluminescence, but also contributes to manifestation of extraordinary effects in dielectric characteristics of such a material.

Currently, colloidal quantum dots (CQDs) have received considerable attention due to their unique properties, such as the ability to control the band gap in a wide range, the tuning of absorption spectra, the possibility of precipitation from solutions, etc. These properties are especially important for research in the field of detection of electromagnetic radiation in the visible and infrared ranges. The paper presents an overview of photodetectors based on colloidal quantum dots lists the most commonly used materials for creating these devices. Technologies for creating efficient and high-speed photodetectors are described. Particular attention is paid to photodetectors based on metal chalcogenides, which are sensitive in the near infrared range. Advantages and disadvantages of photodetectors based on colloidal quantum dots are described. As well as the results of the introduction of CdSe-based CQDs into organic photosensitive structures of the CuPc/PTCDA type are presented.

The effect of colloidal quantum dots on the optical characteristics of photosensitive layers of the perovskite crystal structure has been investigated. The study used a comparative analysis of photosensitive layers with and without quantum dots. As a result, absorption, transmission and photoluminescence spectra were obtained. It can be concluded that the inclusion of CQD in the composition of perovskite leads to an increase of absorption and a decrease of transmission in the short-wavelength region from the peak of photoluminescence of quantum dots. It can also contribute to the shift of perovskite photoluminescence peak to the long-wavelength region.

The optical properties of bromine-doped organic-inorganic perovskite thin layers were investigated. Replacing iodine, which is component of perovskites, with bromine improves film properties due to the formation of a more stable crystal structure. In this study, perovskite films MAPbI2Br, MAPbBr3, FAPbI 3-x Br x , FA 0,85 Cs 0,15 Pb(I 0,85 Br 0,15 ) 3 and Cs0,05(FA x MA 1-x ) 0,95 PbI y Br 3-y , were obtained by spin-coating method. To determine the optimal technological parameters, such as the spin-coating speed, annealing time and temperature, we studied the photoluminescence and absorbance spectra of the created films. It was found that the use of an antisolvent leads to an increase in the photoluminescence intensity, which can be attributed to the formation of a better-quality film with fewer defects.

The simulation of a greenhouse for the Arctic regions was carried out, which operates autonomously using solar and wind energy, as well as adapted to low temperatures and capable of producing plant products directly on the territory of the Russia Federation Arctic zone. To develop the project, a comprehensive work was carried out to study all aspects of the greenhouse installation and all the systems necessary for its successful operation, namely: the design of the greenhouse container, the design of the growing rack, the heating system, the irrigation system, the lighting system, the humidification system, the cooling systems, power supply.

Introduction . The problem of increasing the efficiency of existing photodetectors and creating their new types attracts much research attention. Among new photodetector types are photosensitive structures based on cascade concentrators, whose operational principle involves the absorption of optical radiation followed by its reemission at a longer wavelength and radiation concentration onto a highly efficient small-area photodetector. The absorption and re-emission spectra of each cascade layer depend on the characteristics of the material used. Сolloidal quantum dots are among the most promising materials for cascade layers due to their manufacturing technology, which provides for accurate control over the photoluminescence maximum position. It seems highly relevant to develop and to study photosensitive structures with cascade concentrators of various shapes based on CdS, CdSe/ZnS, and PbS colloidal quantum dots. Aim . To develop photosensitive structures with a wide-range sensitivity spectrum based on concentrators containing arrays of metal chalcogenide CQDs and to study their characteristics. Materials and methods . Cascade photosensitive structures were manufactured based on layers made of polymethyl methacrylate and layers of colloidal quantum dots embedded in a polystyrene matrix. Results . Three-layer concentrators were manufactured with different colloidal quantum dots in each concentrator layers. A 22 % increase in the output power was observed for a three-layer cascade structure based on different cascade layer materials compared to a similar structure using a single layer concentrator. Conclusion . The conducted studies showed an increase in the efficiency of photosensitive structures with a cascade concentrator based on colloidal quantum dots of various types (CdS, CdSe/ZnS, and PbS) in the cascade layers.

Introduction. In view of growing environmental concerns, innovative solutions to ensure electrical energy supply to various devices and systems are required. As a result, renewable energy sources, including those based on solar energy, are attracting much attention. In this context, the development of a Wi-Fi router powered by modern photovoltaic converters seems to be a relevant research task.Aim. Development of a Wi-Fi router powered by modern photovoltaic converters.Materials and methods. The proposed system was developed on the basis of a Wi-Fi router YF360-H and a photovoltaic cell HVL-105/O.Results. Calculations of the developed photovoltaic system were performed; volt-ampere and watt-ampere characteristics of the solar panel were investigated. The solar panel power supply circuit was developed, with the conversion efficiency in the working area achieving 90 %. The capacity of the external battery ensuring the system's autonomous operation for 7 days was determined. A modeling experiment in the MATLAB environment demonstrated the high efficiency of the developed system.Conclusion. According to the conducted calculations, a HVL-105/O photovoltaic cell can be used to power a Wi-Fi router YF360-H under the weather conditions considered most unfavorable for solar cells.

The issues of the perovskite degradation and the stability of perovskite solar cells are studied in this article. The method of vacuum thermal deposition, spray pyrolysis, and spin-coating methods are adopted for the fabrication of different constituents of solar cells to achieve good reproducibility and long lifetime for samples with high efficiency. The applied one-step coating method for creation of perovskite layer is described in detail. It is investigated what exactly leads to the degradation of perovskite solar cells under constant sunlight illumination, because this seems to be one of the biggest obstacles to their commercialization.

В работе изучены эффекты, происходящие при формировании фрактальных микроструктур в проводящих слоях оксидных композиций. Показано, что при протекании токов высокой плотности в слоях оксидов индия-олова, расположенных на стеклянной подложке, возникает динамическая система, сопровождающаяся формированием на поверхности слоя токового канала, задающего траекторию развития фрактальных микроструктур. Сформированы фрактальные микроструктуры различной формы: спиральной, секторальной, лучевой. Показано, что нанесение поверх слоев оксидных композиций дополнительных пленок полимеров визуализирует процессы пробоя, протекающие в структуре. Возникающая при этом увеличенная полимерная фотография дает возможность проводить оценку качества контактных слоев без использования оптической аппаратуры высокого разрешения. Наиболее важным эффектом, сопровождающим образование фрактальных структур, является возникновение люминесценции, связанной с релаксацией возбужденных атомов. Этот аналитический сигнал перспективен для анализа процессов формирования фрактальных структур.

In this paper, we have studied the fractal microstructures that form within conducting layers of oxide compositions and the effects that happen during electrical breakdown. We have determined that application of additional polymer films on top of the layers of oxide compositions allows one to visualize the breakdown processes taking place in the structure. The enlarged "polymer photography" that results in this makes it possible to assess the quality of contact layers without using high-resolution optical equipment.

During the work organic light-emitting structures FTO/PEDOT:PSS//TPD/TPD+CQD CdSe(650)/Alq3/Al with an efficiency value of about 2% were created. The technique for introducing CdSe CQD (650) into the structure of OLED was developed. The change in the electroluminescence spectra in structures with colloidal quantum dots is demonstrated. The decrease in OLED switching on voltage in structures with the PEDOT: PSS layer is demonstrated.

The effects occurring on the formation of fractal microstructures in conductive layers of oxide compounds are investigated. It is demonstrated that during a high-density current flow in the layers of indium tin oxides (ITOs) placed on glass substrate a dynamic system is formed with the subsequent formation of a current channel on the layer's surface, which determines the path of the development of fractal microstructures. Fractal microstructures of varied shapes (spiral, sectoral, and radial) were formed. It is shown that application of an additional polymer thin film on the layers of oxide compounds visualizes the breakdown processes occurring within the structure. Magnified polymer imaging allows to estimate the quality of the layers in contact without high resolution optical equipment. The emergence of luminescence related to the relaxation of excited atoms is identified as the most crucial effect following the formation of fractal structures. This analytical signal is promising in terms of the analysis of the processes of the formation of fractal structures.

We have created organic electroluminescent structures—ITO/TPD/Alq3/Al and ITO/PEDOT:PSS/TPD/Alq3/Al—which are organic light-emitting diodes (OLEDs). Experiments on the incorporation of CdSe/ZnS colloidal quantum dots into the active layer of the structure have been performed. The parameters of the created structures have been determined using optical-spectroscopy methods. The appropriateness of using the method of high-speed vacuum thermal deposition as a main method for the deposition of structural layers has been demonstrated, and the possibility of accelerated formation of layers of the material without disturbing its chemical structure has been shown. By measuring the photoluminescence spectra at different points in samples, we have determined the quality of the obtained structures and plotted maps of the radiation power distribution of the material and of its thickness. Recommendations for the creation of upper contacts and other regions of light-emitting structures have been formulated. We have created organic structures with ITO/PEDOT:PSS/TPD/TPD + CQD’s CdSe/Alq3/Al colloidal quantum dots, in which electroluminescence of CdSe/ZnS quantum dots has been obtained for a wide range of applied voltages. It has been shown that the introduction of colloidal quantum dots into the structure leads to a significant modification of its electroluminescence spectrum.

Phosphor mixture based on colloidal quantum dots (CQDs) has been developed. Devices based on nitride LEDs and phosphor mixtures of CQDs have been created. CRI value of the devices exceeded 95.

The article describes the method for producing a porous GaP: Te at different process parameters. By using SEM were characterized obtained porous structure (pore size, porous layer thickness and etc.).

Selective metal–AlGaN photodetectors based on the Schottky barrier and operating in UV spectral range have been developed. The selective photodiodes based on Ag–AlGaN Schottky barriers of different composition have been manufactured, which has made it possible to improve the photosensitivity in the UV spectral range and eliminate spurious signals in the long-wavelength part of the UV spectral range. This has made it possible to develop visible-blind photodetectors with the long-wavelength edge of photosensitivity lying at the wavelengths less than 350 nm. The width of the photosensitivity spectrum is within 15–40 nm, depending on the thickness of the Ag layer, which varies from 15 to 150 nm. The proper choice of the composition of the Al x Ga1–x N solid solution ensures increase in the photoresponse and reduction of the FWHM spectrum width up to 11 nm by matching peaks of the Ag transmission spectrum and the absorption spectrum of the epitaxial layer. The sensitivity is 0.071 A/W. The combination of effects of wideband window and overthe- barrier transfer has made it possible to create the ultraselective UV photodetectors based on Au–AlGaN structures with a half-width of the photosensitivity spectrum of 5–6 nm for the wave range 350—375 nm and a sensitivity of up to 140 mA/W. Based on a structure with the upper Al x Ga1–x N epitaxial layer (with the AlN content x = 0.1 or x = 0.06), selective photodetectors with the maximum photosensitivity at wavelengths of 355 nm and 362 nm have been developed. Application of an additional less wideband GaN layer has made it possible to independently control the short-wavelength and long-wavelength boundaries of the sensitivity range.

This is the study of the properties of CdSe/ZnS and CdSeZnS/ZnS colloidal quantum dots (CQDs) with peaks of the photoluminescence spectra in the range of wavelengths from 500 to 700 nm. Parameters of these colloidal quantum dots were modelled and then compared to experimental data from transmission electron microscopy (TEM). Diameters of examined quantum dots were estimated to range from 0.6 to 5.7 nm.

The selective Au-AlGaN-based Schottky barrier photodetectors operating in different UV ranges have been fabricated. The wide bandgap window effect and the over barrier emission are proposed as methods for control of the photosentivity spectrum. Selective photodetectors were fabricated with the following parameters: a full width at half maximum of 5-6 nm with a maximum at 355 nm, 362 nm, 366 nm, and a sensitivity up to 140 mA / W.