Dina Bakranova

AI-enabled intelligent sensing systems are increasingly used in Internet of Things (IoT) applications, edge–cloud environments, industrial automation, and cyber-physical systems. Their design, however, requires simultaneous consideration of sensing performance, computational demand, communication requirements, and limited energy resources. Much of the existing literature addresses these aspects separately, although their interactions often determine the performance and autonomy of the complete sensing platform. This review examines energy-aware AI-enabled sensing systems from a system-level perspective, with particular attention to the trade-offs that arise under resource-constrained operating conditions. Representative studies spanning intelligent sensing, embedded intelligence, edge–cloud computing, wireless sensor networks, AIoT, and energy-aware system design are analyzed to identify common architectural principles and design constraints. Four recurring system-level trade-offs are considered, namely measurement accuracy versus energy consumption, latency versus energy savings, local computation versus communication load, and model fidelity versus computational efficiency. The review further develops a multidimensional taxonomy of energy-aware sensing architectures based on energy source, operational mode, processing model, and communication strategy. These elements are integrated into a common framework linking sensing performance, computational requirements, communication demand, and energy allocation. Particular attention is also given to hybrid and multimodal sensing, distributed intelligence, TinyML, hardware-aware model deployment, and adaptive resource allocation. Remaining challenges include scalability, operation under changing sensing conditions, cross-platform evaluation, trustworthy embedded AI, and the transition from laboratory demonstrations to long-term deployment. The resulting system-level perspective provides a basis for designing intelligent sensing platforms in which sensing, computation, communication, and energy resources are considered jointly rather than optimized in isolation.

In this work, we report the fabrication of a relatively efficient, cheap, and stable silicon-based photocatalyst for water purification. Silicon-nickel composites were fabricated by mixing and grinding metallurgical silicon with commercial nickel nanoparticles. Experiments demonstrate a significant improvement in methylene blue degradation under UV—and especially under solar—conditions. About half of the contaminants were degraded after 100 min. Theoretical modeling demonstrates the effects of impurities in subsurface layers on absorbance and on the release of hydroxyl radicals from silicon.

This study analyzes the influence of environmental parameters on the efficiency of photocatalytic processes for air purification. Modern photocatalytic air purification systems utilize light-activated semiconductor materials to generate reactive oxygen species capable of oxidizing pollutants to less toxic products. Experimental data indicate significant progress in the development of photocatalysts based on oxide and heterostructured materials. However, the high activity of photocatalytic materials demonstrated in laboratory conditions is not always reproducible under real-world environmental conditions. The study focused on the influence relative humidity, solar radiation intensity, ambient temperature, and mass transfer conditions on the kinetics of photocatalytic reactions and the availability of active surface sites. It was found that the effect of humidity is nonlinear and is determined by the balance between the formation of hydroxyl radicals and the competing adsorption of water molecules and target pollutants. The efficiency of photocatalytic processes under real-world conditions is determined not only by external environmental parameters but also by the structural design of the systems themselves. Integrated photocatalytic structures, such as fibrous membranes and composite materials, offer the most promise. These structures provide simultaneous filtration, adsorption, and catalytic oxidation of pollutants, as well as improved mass transfer to active sites. This architecture significantly improves the stability and reproducibility of photocatalytic activity under varying environmental conditions. A further evaluation of practical efficiency was conducted, taking into account the formation of reaction intermediates and their potential impact on human health. It was shown that the use of photocatalytic oxidation without preor concomitant filtration can lead to the formation of undesirable byproducts, whereas combined systems provide more thorough air purification and reduce the negative impact on cardiorespiratory parameters. Overall, the obtained results indicate the need to move from a material-based approach to a systems-based design of photocatalytic technologies, taking into account their real-world operating conditions.

This study investigates the effect of wet chemical etching on impurity removal and the photocatalytic properties of metallurgical-grade silicon (Si) powder. The Si powder was subjected to a two-stage high-energy ball milling process followed by acid etching using an HF:HCl:HNO ₃ mixture under controlled conditions. The morphology and composition of the samples were analyzed using transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS). The results revealed particle sizes below 200 nm and a well-defined crystalline structure with an interplanar spacing of ~0.20 nm, corresponding to the Si (220) plane. EDS analysis confirmed the effective removal of metallic impurities (K, Ca, Ni) and carbon, while an increase in oxygen (~8 at.%) and nitrogen (~12.2 at.%) content was observed due to surface oxidation and chemical treatment. The photocatalytic activity of etched (Si _p ) and untreated (Si _s ) silicon powders was evaluated via the degradation of methylene blue (10 mg/L) under UV irradiation. After 120 minutes, the concentration ratio C _t /C ₀ decreased to ~0.18 for Si _p , compared to ~0.9 for Si _s . A more than fourfold reduction in the absorption peak at 664 nm was observed for Si _p , indicating enhanced dye degradation. Kinetic analysis showed that the degradation process follows a pseudo-first-order model, with higher rate constants for the etched samples. The improved performance is attributed to impurity removal, reduced charge carrier recombination, and increased active surface sites. These results demonstrate that wet chemical etching is an effective and scalable approach to enhance the functional properties of metallurgical silicon for environmental photocatalytic applications.

Загрязнение атмосферного воздуха остаётся одним из ключевых факторов риска для здоровья человека, что обуславливает необходимость разработки эффективных технологий удаления газообразных загрязнителей. Фотокаталитические системы рассматриваются как перспективное направление благодаря способности к минерализации загрязняющих веществ в условиях непрерывного потока. Однако их эффективность традиционно оценивается по степени удаления или кажущимся константам скорости, что не учитывает влияние расхода воздуха, геометрии реактора и площади активной поверхности и затрудняет корректное сопоставление различных систем. В настоящей работе предложена удельная поверхностная скорость удаления rs в качестве универсальной метрики для анализа фотокаталитических систем различного типа и масштаба. На основе анализа литературных данных показано, что значения rs изменяются на несколько порядков в зависимости от условий эксплуатации и типа системы. Для газофазных процессов rs достигает порядка 10-2 мг· м-2 · с-1, тогда как для водных систем снижается до 10-7 мг·м-2·с-1 вследствие различий в коэффициентах диффузии и сопротивлении массопереносу. Установлено, что при переходе от лабораторных к проточным и натурным системам определяющую роль начинают играть процессы массопереноса и гидродинамика потока. В условиях низких скоростей потока эффективность определяется поверхностной кинетикой, тогда как при увеличении расхода воздуха процесс переходит в область, ограниченную массопереносом. Дополнительное влияние оказывают влажность, температура, спектральные характеристики излучения, а также способ фиксации фотокатализатора и устойчивость покрытий. Показано, что использование метрики rₛ позволяет перейти от описания локальной кинетики к системному анализу фотокаталитических процессов, учитывающему реальные условия эксплуатации. Полученные результаты подтверждают необходимость перехода от материал-центрированного подхода к системному проектированию фотокаталитических систем очистки воздуха. Ключевые слова: фотокаталитическая очистка воздуха, газофазные загрязнители, атмосферное загрязнение, гидродинамика потока, массоперенос.

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.

В данной работе представлена поэтапная методика синтеза гетероструктуры BiVO4/ZnO, сформированной на основе нанотрубчатых массивов оксида цинка. На первом этапе синтеза наностержни ZnO были получены гидротермальным методом, который позволяет контролировать морфологию, размеры и однородность образцов. Далее полученные наностержни подвергались электрохимическому травлению, в результате чего происходило селективное растворение центральной части структур и формирование полых нанотрубок ZnO с развитой удельной поверхностью. Синтезированные ZnO-нанотрубки использовались в качестве шаблона для последующего построения гетероструктуры BiVO4/ZnO. Осаждение BiVO4 осуществлялось двухэтапным методом, обеспечивающим равномерное распределение материала по поверхности нанотрубок и формирование квантовых точек BiVO4, что способствует улучшению межфазного контакта и разделению фотогенерированных носителей заряда. Для комплексной характеристики полученных структур применялись методы сканирующей электронной микроскопии (SEM), просвечивающей электронной микроскопии (TEM) и рентгеновской дифрактометрии (XRD), позволяющие исследовать морфологию, внутреннюю структуру и фазовый состав образцов. Кроме того, был проведён предварительный анализ структур ZnO в форме наностержней и нанотрубок, выполнен обзор литературных данных и осуществлён их сравнительный анализ с точки зрения перспектив применения в фотоэлектрохимических системах. Ключевые слова: квантовые точки, оксид цинка, ванадат висмута, гидротермальный синтез, нанотрубки, наностержни.

Silicon carbide (SiC) has emerged as a robust and tunable semiconductor for advanced photocatalytic applications. This review provides a comprehensive overview of recent progress in the development of SiC-based materials for environmental remediation and solar-driven hydrogen production. Key aspects discussed include morphological engineering, heterostructure design, doping strategies, and plasmonic enhancement. Emphasis is placed on structure–activity relationships, insights from density functional theory (DFT) and machine learning (ML) models, and synergistic effects in composite systems. This review concludes with a critical analysis of current challenges and future research directions, highlighting the potential of SiC implementation as a sustainable platform for next-generation photocatalytic technologies.