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Perovskite solar cells (PSCs) with mesoporous TiO2 (mp‐TiO2) as the electron transport material attain power conversion efficiencies (PCEs) above 22%; however, their poor long‐term stability is a critical issue that must be resolved for commercialization. Herein, it is demonstrated that the long‐term operational stability of mp‐TiO2 based PSCs with PCE over 20% is achieved by isolating devices from oxygen and humidity. This achievement attributes to systematic understanding of the critical role of oxygen in the degradation of PSCs. PSCs exhibit fast degradation under controlled oxygen atmosphere and illumination, which is accompanied by iodine migration into the hole transport material (HTM). A diffusion barrier at the HTM/perovskite interface or encapsulation on top of the devices improves the stability against oxygen under light soaking. Notably, a mp‐TiO2 based PSC with a solid encapsulation retains 20% efficiency after 1000 h of 1 sun (AM1.5G including UV) illumination in ambient air. The long‐term photostability under AM1.5G simulated 1 sun illumination including UV is demonstrated with the perovskite solar cell exceeding power conversion efficiency of 20%. This achievement stems from understanding the role of oxygen on the degradation under illumination. Oxygen induces iodine migration from the perovskite to a hole transport layer, which interrupts the charge transport through the interface.

The extensive use of financial technologies and innovations in the provision and utilization of financial products and services causes new risks that require constant attention. The article aims to improve innovation risk management methods to increase the operational stability of financial institutions in Ukraine. By generalizing international practice, the types of innovation risks are classified, and their impact on the activities of financial institutions and consumers is characterized. The attention is drawn to the control strengthening over the impact of operational and regulatory risks, based on important theoretical provisions contained in WBG, BIS, BCBS, and FSB documents. An organizational scheme for the interaction of a financial institution and an IT company is proposed to conclude “smart contracts” based on the use of a cloud service and blockchain technology. The authors propose additional methods of insurance protection and compensation for losses caused by the implementation of risks of using ICT and innovation based on creating the Collective Risk Insurance Fund of financial institutions; offer approaches to the calculation of variable and fixed parts of the contribution to the insurance fund for certain groups of financial institutions. It is concluded that to maintain the proper operational stability of financial institutions in Ukraine, it is necessary to introduce additional collective compensation methods for the risks of innovation and the strengthening of cyber threats.

Organic–inorganic halide perovskite solar cells (PSCs) demonstrate impressive power conversion efficiencies (PCEs), yet they encounter significant issues concerning interfacial defects and stability. This work mitigates these constraints by implementing a dual interfacial passivation approach utilizing graphitic carbon nitride (g‐C 3 N 4 ) at the interfaces of the Fe 2 O 3 electron transport layer (ETL)/CsFAMA perovskite (PVK) and PVK/hole transport layer (HTL). The Fe 2 O 3 ETL, despite its chemical stability and cost‐effectiveness, is hindered by surface roughness and trap states that impede efficient charge extraction. Through the incorporation of g‐C 3 N 4 , a nitrogen‐rich 2D semiconductor, we attained defect passivation through coordination with undercoordinated Pb 2+ ions and halide vacancies, thereby inhibiting ion migration and improving interfacial energy alignment. Structural characterization (XRD, Raman, scanning electron microscope [SEM]) confirms the layered morphology of g‐C 3 N 4 and its compatibility with the PVK matrix, while optical analysis reveals enhanced light absorption (400–550 nm) and retained transparency (~80%). The dual‐modified devices achieved a champion PCE of 15.97% (12.89% for the control) and a low hysteresis index (HI) of 0.01 (0.06 for the control) with a high V OC = 1.12 V, J SC = 19.49 mA cm −2 , and FF 73.19%. Electrochemical impedance spectroscopy and photoluminescence studies demonstrate reduced charge recombination and improved carrier extraction. Critically, the modified devices retain approximately 87% of their initial PCE after 500 h under continuous illumination, highlighting exceptional operational stability. This work establishes dual interfacial engineering with g‐C 3 N 4 as a robust strategy for advancing efficient, hysteresis‐free, and durable PVK photovoltaics, bridging the gap toward commercial viability.

HighlightsSelf-powered direct X-ray detectors, based on FAPbBr3 255-nm-thick films deposited onto mesoporous TiO2 scaffolds, can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss, demonstrating ultra-high operational stability.Bulk specific sensitivity is evaluated to be 7.28 C Gy−1 cm−3 at 0 V, an unprecedented value in the field of thin-film-based photoconductors and photodiodes for “hard” X-rays. Sensitivity of submicrometer-thick perovskite films to the X-rays produced by a medical linear accelerator used for cancer treatment is here demonstrated for the first time. Metal-halide perovskites are revolutionizing the world of X-ray detectors, due to the development of sensitive, fast, and cost-effective devices. Self-powered operation, ensuring portability and low power consumption, has also been recently demonstrated in both bulk materials and thin films. However, the signal stability and repeatability under continuous X-ray exposure has only been tested up to a few hours, often reporting degradation of the detection performance. Here it is shown that self-powered direct X-ray detectors, fabricated starting from a FAPbBr3 submicrometer-thick film deposition onto a mesoporous TiO2 scaffold, can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss, demonstrating ultra-high operational stability and excellent repeatability. No structural modification is observed after irradiation with a total ionizing dose of almost 200 Gy, revealing an unexpectedly high radiation hardness for a metal-halide perovskite thin film. In addition, trap-assisted photoconductive gain enabled the device to achieve a record bulk sensitivity of 7.28 C Gy−1 cm−3 at 0 V, an unprecedented value in the field of thin-film-based photoconductors and photodiodes for “hard” X-rays. Finally, prototypal validation under the X-ray beam produced by a medical linear accelerator for cancer treatment is also introduced.

HighlightsHigh-quality large-area SnO2 films are fabricated by chemical bath deposition with the addition of KMnO4.The presence of K and Mn ions can improve both the crystallinity and the phase stability of perovskites and reduce hysteresis of devices simultaneously.Perovskite solar modules (22.4 and 91.8 cm2) are demonstrated with active area efficiencies of 17.26% and 13.72%, respectively, and the 22.4 cm2 perovskite solar module exhibits a T80 operation lifetime exceeding 1000 h in ambient condition.Tin dioxide (SnO2) has been demonstrated as one of the promising electron transport layers for high-efficiency perovskite solar cells (PSCs). However, scalable fabrication of SnO2 films with uniform coverage, desirable thickness and a low defect density in perovskite solar modules (PSMs) is still challenging. Here, we report preparation of high-quality large-area SnO2 films by chemical bath deposition (CBD) with the addition of KMnO4. The strong oxidizing nature of KMnO4 promotes the conversion from Sn(II) to Sn(VI), leading to reduced trap defects and a higher carrier mobility of SnO2. In addition, K ions diffuse into the perovskite film resulting in larger grain sizes, passivated grain boundaries, and reduced hysteresis of PSCs. Furthermore, Mn ion doping improves both the crystallinity and the phase stability of the perovskite film. Such a multifunctional interface engineering strategy enabled us to achieve a power conversion efficiency (PCE) of 21.70% with less hysteresis for lab-scale PSCs. Using this method, we also fabricated 5 × 5 and 10 × 10 cm2 PSMs, which showed PCEs of 15.62% and 11.80% (active area PCEs are 17.26% and 13.72%), respectively. For the encapsulated 5 × 5 cm2 PSM, we obtained a T80 operation lifetime (the lifespan during which the solar module PCE drops to 80% of its initial value) exceeding 1000 h in ambient condition.

HighlightsTwo series of terpolymers with improved photostability were realized by the introduction of appropriate ratio of antioxidant butylated hydroxytoluene unit containing side chains.All-polymer solar cells and organic photodetectors (OPDs) with these terpolymers as both donors and acceptors have been prepared with simultaneously improved efficiency and stability.A feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of organic solar cells and OPDs is proposed.It is of vital importance to improve the long-term and photostability of organic photovoltaics, including organic solar cells (OSCs) and organic photodetectors (OPDs), for their ultimate industrialization. Herein, two series of terpolymers featuring with an antioxidant butylated hydroxytoluene (BHT)-terminated side chain, PTzBI-EHp-BTBHTx and N2200-BTBHTx (x = 0.05, 0.1, 0.2), are designed and synthesized. It was found that incorporating appropriate ratio of benzothiadiazole (BT) with BHT side chains on the conjugated backbone would induce negligible effect on the molecular weight, absorption spectra and energy levels of polymers, however, which would obviously enhance the photostability of these polymers. Consequently, all-polymer solar cells (all-PSCs) and photodetectors were fabricated, and the all-PSC based on PTzBI-EHp-BTBHT0.05: N2200 realized an optimal power conversion efficiency (PCE) approaching ~ 10%, outperforming the device based on pristine PTzBI-EHp: N2200. Impressively, the all-PSCs based on BHT-featuring terpolymers displayed alleviated PCEs degradation under continuous irradiation for 300 h due to the improved morphological and photostability of active layers. The OPDs based on BHT-featuring terpolymers achieved a lower dark current at − 0.1 bias, which could be stabilized even after irradiation over 400 h. This study provides a feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of OSCs and OPDs.

Among the available technologies, the dyna-sand filter has gained attention due to its continuous filtration and sand washing mechanism, which provides an advantage in maintaining stable operation. Nevertheless, its performance under variable heights of washout weir with constant solid loads and the optimization of its washing system remain areas that require further study. This study investigates the use of the dyna-sand filter in water treatment facilities, focusing on the alteration of the washout weir to improve efficiency and reduce washout water amount. The study evaluates the filter’s performance under fixed influent total suspended solids (TSS) concentration and constant filtration rate (ROF), aiming to demonstrate the advantages of this alteration in enhancing removal efficiency, operational stability, and water saving through a laboratory-scale pilot. The average washout discharge fell from 0.788 to 0.486 L/min, a 38.3% reduction in washout water amount. As a result, filtered water production rose by nearly 2.2%, indicating more efficient hydraulic operation. These findings confirm that raising the washout weir by 4 cm improved filtration and reduced washout water loss. This, in turn, enhanced system productivity and the quality of washwater produced, assuming a consistent flow rate and solid load.

Biocatalytic syntheses often require unfavorable conditions, which can adversely affect enzyme stability. Consequently, improving the stability of biocatalysts is needed, and this is often achieved by immobilization. In this study, we aimed to compare the stability of soluble and immobilized transaminases from different species. A cysteine in a consensus sequence was converted to a single aldehyde by the formylglycine-generating enzyme for directed single-point attachment to amine beads. This immobilization was compared to cross-linked enzyme aggregates (CLEAs) and multipoint attachments to glutaraldehyde-functionalized amine- and epoxy-beads. Subsequently, the reactivity and stability (i.e., thermal, storage, and solvent stability) of all soluble and immobilized transaminases were analyzed and compared under different conditions. The effect of immobilization was highly dependent on the type of enzyme, the immobilization strategy, and the application itself, with no superior immobilization technique identified. Immobilization of HAGA-beads often resulted in the highest activities of up to 62 U/g beads, and amine beads were best for the hexameric transaminase from Luminiphilus syltensis. Furthermore, the immobilization of transaminases enabled its reusability for at least 10 cycles, while maintaining full or high activity. Upscaled kinetic resolutions (partially performed in a SpinChemTM reactor) resulted in a high conversion, maintained enantioselectivity, and high product yields, demonstrating their applicability.

Amine transaminases (ATA) convert ketones into optically active amines and are used to prepare active pharmaceutical ingredients and building blocks. Novel ATA can be identified in protein databases due to the extensive knowledge of sequence-function relationships. However, predicting thermo- and operational stability from the amino acid sequence is a persisting challenge and a vital step towards identifying efficient ATA biocatalysts for industrial applications. In this study, we performed a database mining and characterized selected putative enzymes of the β-alanine:pyruvate transaminase cluster (3N5M) — a subfamily with so far only a few described members, whose tetrameric structure was suggested to positively affect operational stability. Four putative transaminases (TA-1: Bilophilia wadsworthia, TA-5: Halomonas elongata , TA-9: Burkholderia cepacia , and TA-10: Burkholderia multivorans ) were obtained in a soluble form as tetramers in E. coli . During comparison of these tetrameric with known dimeric transaminases we found that indeed novel ATA with high operational stabilities can be identified in this protein subfamily, but we also found exceptions to the hypothesized correlation that a tetrameric assembly leads to increased stability. The discovered ATA from Burkholderia multivorans features a broad substrate specificity, including isopropylamine acceptance, is highly active (6 U/mg) in the conversion of 1-phenylethylamine with pyruvate and shows a thermostability of up to 70 °C under both, storage and operating conditions. In addition, 50% (v/v) of isopropanol or DMSO can be employed as co-solvents without a destabilizing effect on the enzyme during an incubation time of 16 h at 30 °C. Key points • Database mining identified a thermostable amine transaminase in the β-alanine:pyruvate transaminase subfamily . • The tetrameric transaminase tolerates 50% DMSO and isopropanol under operating conditions at 30 °C . • A tetrameric structure is not necessarily associated with a higher operational stability Graphical abstract

One of the most important priorities for all countries with property beyond the Arctic Circle and territories located in permafrost areas is the development of special construction technologies and systems. The required conditions are met by insulation systems based on seamless insulation shells made of polyethylene foam. The study of the strength and performance properties of polyethylene foam and its combinability was carried out according to standard methods and using the methods of experimental design and the analytical processing of the results. The change in material properties at negative temperatures was determined based on the results of climatic tests, followed by an evaluation of creep under load. The evaluation of the effectiveness of the design solutions was carried out using special computer programs. It was found that the performance characteristics of products made of polyethylene foam (rolls, mats) meet the requirements for insulation materials used at temperatures down to −60 °C. The resulting material is moderately combustible, which must be taken into account when developing recommendations for its use in insulation systems. A nomogram has been developed that makes it possible to predict the properties of a material and solve formulation problems. Insulation systems were developed, and a visualisation of the thermal fields of the insulation systems of the external walls and ceilings of a building was carried out.