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Metal-halide perovskites have been widely investigated in the photovoltaic sector due to their promising optoelectronic properties and inexpensive fabrication techniques based on solution processing. Here we report the development of inorganic CsPbBr 3 -based photoanodes for direct photoelectrochemical oxygen evolution from aqueous electrolytes. We use a commercial thermal graphite sheet and a mesoporous carbon scaffold to encapsulate CsPbBr 3 as an inexpensive and efficient protection strategy. We achieve a record stability of 30 h in aqueous electrolyte under constant simulated solar illumination, with currents above 2 mA cm −2 at 1.23 V RHE . We further demonstrate the versatility of our approach by grafting a molecular Ir-based water oxidation catalyst on the electrolyte-facing surface of the sealing graphite sheet, which cathodically shifts the onset potential of the composite photoanode due to accelerated charge transfer. These results suggest an efficient route to develop stable halide perovskite based electrodes for photoelectrochemical solar fuel generation. While photoelectrochemical cells may offer access to solar fuels from a single integrated device, halide perovskite photoelectrodes are difficult to use due to their inherent moisture sensitivity. Here, the authors protect perovskite photoanodes with graphite sheets to boost their stability in water.

Metal halide perovskites (MHPs) constitute a rich library of materials with huge potential for disruptive optoelectronic technologies. Their main strength comes from the possibility of easily tuning their bandgap to integrate them in devices with different functionalities — in principle. In reality, this cannot be achieved yet. In fact, whereas defect tolerance can be claimed for MHPs with a bandgap of about 1.6 eV, the model system that is the object of intense investigations, MHPs with lower and higher bandgaps are far from being defect-tolerant. These materials show various forms of instabilities that are mainly driven by strong defect activity. Here we critically assess the most recent advances in elucidating the physical and chemical activity of defects in both high-bandgap and low-bandgap MHPs, while correlating it to performance and stability losses, especially for solar cells, the driving application for these materials. We also provide an overview of the strategies so far implemented to eventually overcome the remaining materials-based and device-based challenges. Metal halide perovskites (MHPs) have substantial potential for solar cell applications. This Review critically assesses recent advances in elucidating the physical and chemical activity of defects in both high-bandgap and low-bandgap MHPs, and correlates it to performance and stability losses.

The prevalence of background hole doping in tin halide perovskites usually dominates their recombination dynamics. The addition of excess Sn halide source to the precursor solution is the most frequently used approach to reduce the hole doping and reveals photo‐carrier dynamics related to defects activity. This study presents an experimental and theoretical investigation on defects under light irradiation in tin halide perovskites by combining measurements of photoluminescence with first principles computational modeling. It finds that tin perovskite thin films prepared with an excess of Sn halide sources exhibit an enhancement of the photoluminescence intensity over time under continuous excitation in inert atmosphere. The authors propose a model in which light irradiation promotes the annihilation of VSn2−/Sni2+ Frenkel pairs, reducing the deep carrier trapping centers associated with such defect and increasing the radiative recombination. Importantly, these observations can be traced in the open‐circuit voltage dynamics of tin‐based halide perovskite solar cells, implying the relevance of controlling the Sn photochemistry to stabilize tin perovskite devices. Tin‐based perovskite thin films exhibit a photoinduced enhancement in the photoluminescence intensity over time due to annihilation of VSn2−/Sni2+ Frenkel pairs promoted by continuous illumination. Such annihilation reduces the nonradiative deep carrier trapping associated with such a defect and promotes radiative recombinations.

This roadmap provides a comprehensive overview of the latest advancements in lead-free perovskite materials for photovoltaic and photoelectrochemical /photocatalytic applications. It highlights the urgent need for sustainable energy solutions, emphasizing the role of lead-free perovskites in addressing challenges related to toxicity, scalability, and efficiency. The roadmap is designed to guide the reader from application-driven perspectives to fundamental materials insights, characterization techniques, fabrication strategies and overreaching sustainability considerations. The document explores key material families, including tin-, bismuth-, antimony-, and copper-based perovskites, detailing their optoelectronic properties, fabrication techniques, and application potential. Special attention is given to advanced characterization methods, green processing strategies, the integration of artificial intelligence and machine learning for material design and optimization and lifecycle impact assessments to ensure environmental sustainability. By bringing together insights from global research communities, this roadmap serves as a strategic guide for advancing lead-free perovskite technology, fostering interdisciplinary collaboration, and accelerating the transition to next-generation solar energy solutions.

Halide perovskites have become a popular material to fabricate photovoltaic devices for the conversion of sunlight into electricity. Perovskite solar cells have shown extraordinary performance, reaching power conversion efficiencies of over 24% in less than a decade. Some of the reasons for their success are the high light absorption and the possibility of using low cost solution-based fabrication. Perovskite devices are notably efficient, but they still suffer from instabilities that challenge their commercialisation. Indeed, perovskite solar cells degrade when exposed to moisture, high temperature and light, causing irreversible loss of efficiency. In this work, different strategies for improving the stability of perovskite solar cells have been studied. Humidity is one of the most invasive factors that affects perovskite solar cell stability. Water molecules easily penetrate through the extraction layers reaching the perovskite structure and irreversibly degrading the absorber film. Moisture-induced degradation of perovskite solar cells can be minimised by modifying the top perovskite surface with interfacial hydrophobic thin layers and by passivating the grain boundaries. In this work, for example, the perovskite surface is treated with CH3NH3PbI3 nanocrystals capped with long chain ligands (oleic acid and oleylamine), significantly enhancing the film’s hydrophobicity. Bulkier and larger organic cations, like tetrabutylammonium, are also incorporated through the absorber perovskite thin film, passivating grain boundaries and improving the stability of perovskite solar cells when exposed to ambient conditions without encapsulation (relative humidity higher than 50%). Another method to limit the moisture-induced degradation of perovskite solar cells is through encapsulation. Here, a flexible and robust graphite sheet is used to protect halide perovskite devices from water. Instabilities are also manifested as light-induced defect formation and ion migration through the perovskite film, which can lead to material degradation. It has been shown that under-coordinated surface sites and grain boundaries act as defect reservoirs in perovskite films. Photo-instabilities can therefore be limited by passivating the surface of perovskite films. Here, 5-aminovaleric acid iodide is used to effectively passivate the surface defects of methylammonium lead iodide, photostabilising the perovskite film under continuous illumination, eliminating the formation of lightinduced defects. Light-induced ion migration also causes halide segregation in mixed halide (I and Br) perovskite compositions. Here, it is shown that by incorporating 5-aminovaleric acid iodide in triple cation mixed halide perovskites to passivate grain boundaries, halide segregation is arrested for over 1 h under continuous illumination. Finally, perovskite structures are unstable when exposed to high temperatures. Previous reports have shown that methylammonium lead iodide films tend to degrade over time when heated at 85 °C in ambient air through volatilization of the organic cation. In this work, the use of fully inorganic perovskite materials obtained by substituting Cs for the methylammonium cation considerably improve the thermal stability of perovskite films, which are found to be stable during heating in air at temperatures higher than 350 °C. Not only the MAPbI3 perovskite film itself, but also the solar cell device as a whole is particularly unstable when exposed to high temperature. The organic hole extraction layers are indeed prone to thermal instability and undesirable side reactions with metal contacts tend to be induced at high temperatures. To avoid degradation of the hole transporting materials and side reactions with metals, hole-conductor free architectures made by infiltrating porous layers of carbon, ZrO2 and TiO2 are used. In this work, carbon solar cells with photovoltages as high as 1.45V are achieved by using CsPbBr3 as infiltrating absorber material.

Metal-halide perovskites have been widely investigated in the photovoltaic sector due to their promising optoelectronic properties and inexpensive fabrication techniques based on solution processing. Here we report the development of inorganic CsPbBr -based photoanodes for direct photoelectrochemical oxygen evolution from aqueous electrolytes. We use a commercial thermal graphite sheet and a mesoporous carbon scaffold to encapsulate CsPbBr as an inexpensive and efficient protection strategy. We achieve a record stability of 30 h in aqueous electrolyte under constant simulated solar illumination, with currents above 2 mA cm at 1.23 V . We further demonstrate the versatility of our approach by grafting a molecular Ir-based water oxidation catalyst on the electrolyte-facing surface of the sealing graphite sheet, which cathodically shifts the onset potential of the composite photoanode due to accelerated charge transfer. These results suggest an efficient route to develop stable halide perovskite based electrodes for photoelectrochemical solar fuel generation.

Functional magnetic resonance imaging (fMRI) studies have reported multiple activation foci associated with a variety of conditions, stimuli or tasks. However, most of these studies used fewer than 40 participants. After extracting data (number of subjects, condition studied, number of foci identified and threshold) from 94 brain fMRI meta-analyses (k = 1,788 unique datasets) published through December of 2011, we analyzed the correlation between individual study sample sizes and number of significant foci reported. We also performed an analysis where we evaluated each meta-analysis to test whether there was a correlation between the sample size of the meta-analysis and the number of foci that it had identified. Correlation coefficients were then combined across all meta-analyses to obtain a summary correlation coefficient with a fixed effects model and we combine correlation coefficients, using a Fisher's z transformation. There was no correlation between sample size and the number of foci reported in single studies (r = 0.0050) but there was a strong correlation between sample size and number of foci in meta-analyses (r = 0.62, p<0.001). Only studies with sample sizes <45 identified larger (>40) numbers of foci and claimed as many discovered foci as studies with sample sizes ≥ 45, whereas meta-analyses yielded a limited number of foci relative to the yield that would be anticipated from smaller single studies. These results are consistent with possible reporting biases affecting small fMRI studies and suggest the need to promote standardized large-scale evidence in this field. It may also be that small studies may be analyzed and reported in ways that may generate a larger number of claimed foci or that small fMRI studies with inconclusive, null, or not very promising results may not be published at all.

Nurse turnover affects both patient care and health care costs, with turnover intention reflecting employees’ desire to leave an organization. This systematic review examines factors that contribute to turnover intention among OR nurses. A search of quantitative and qualitative studies in PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature, PsycInfo, and Embase identified 11 studies meeting the inclusion criteria. The contributing factors were categorized into individual and work‐environment factors, with the latter further divided into job attributes and work‐related issues. Key factors such as job satisfaction, age, and work experience were strongly associated with increased turnover intention. Addressing these factors is crucial for retaining OR nurses and improving health care outcomes. Given the complexity of factors involved, future research should adopt more standardized approaches, including consistent definitions and methodologies, to enable accurate comparisons and effective interventions. Then, strategies to improve job satisfaction and working conditions are recommended.

Numerous functional magnetic resonance imaging (fMRI) studies have reported sex differences. To empirically evaluate for evidence of excessive significance bias in this literature, we searched for published fMRI studies of human brain to evaluate sex differences, regardless of the topic investigated, in Medline and Scopus over 10 years. We analyzed the prevalence of conclusions in favor of sex differences and the correlation between study sample sizes and number of significant foci identified. In the absence of bias, larger studies (better powered) should identify a larger number of significant foci. Across 179 papers, median sample size was n = 32 (interquartile range 23-47.5). A median of 5 foci related to sex differences were reported (interquartile range, 2-9.5). Few articles (n = 2) had titles focused on no differences or on similarities (n = 3) between sexes. Overall, 158 papers (88%) reached “positive” conclusions in their abstract and presented some foci related to sex differences. There was no statistically significant relationship between sample size and the number of foci (−0.048% increase for every 10 participants, p = 0.63). The extremely high prevalence of “positive” results and the lack of the expected relationship between sample size and the number of discovered foci reflect probable reporting bias and excess significance bias in this literature.

Cyclin-dependent kinase 5 (Cdk5) is an atypical proline-directed serine/threonine protein kinase well-characterized for its role in the central nervous system rather than in the cell cycle. Indeed, its dysregulation has been strongly implicated in the progression of synaptic dysfunction and neurodegenerative diseases, such as Alzheimer’s disease (AD) and Parkinson’s disease (PD), and also in the development and progression of a variety of cancers. For this reason, Cdk5 is considered as a promising target for drug design, and the discovery of novel small-molecule Cdk5 inhibitors is of great interest in the medicinal chemistry field. In this context, we employed a machine learning-based virtual screening protocol with subsequent molecular docking, molecular dynamics simulations and binding free energy evaluations. Our virtual screening studies resulted in the identification of two novel Cdk5 inhibitors, highlighting an experimental hit rate of 50% and thus validating the reliability of the in silico workflow. Both identified ligands, compounds CPD1 and CPD4, showed a promising enzyme inhibitory activity and CPD1 also demonstrated a remarkable antiproliferative activity in ovarian and colon cancer cells. These ligands represent a valuable starting point for structure-based hit-optimization studies aimed at identifying new potent Cdk5 inhibitors.