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The urgent necessity to remove dangerous lead from the commonly used metal halide perovskite solar cells (PSCs) requires the exploration of effective and reliable lead-free perovskite substitutes. In this study, we conduct a performance analysis of Sn-based PSCs incorporating a low-temperature indium sulfide electron transporting layer (ETL) and use SCAPS-1D simulation to evaluate the PSC performance. We investigate multiple parameters that determine the PSC performance, such as the thickness and defect density of the Sn-based perovskite layer, as well as the defect density at the ETL/perovskite interface. The optimization procedure produced outstanding outcomes with maximum power conversion efficiency (PCE) of 21.57%, 24.03%, and 21.93% for CsSnI3, FASnI3, and MASnI3, respectively. The proposed device structure and parameters could potentially advance the experimental work and provide a new approach for optimizing the construction of Sn-based PSCs, thereby opening up new possibilities for future study in this field. [ABSTRACT FROM AUTHOR]

The enhancement of the photovoltaic performance upon the aging process at particular environment is often observed in perovskite solar cells (PSCs), particularly for the devices with 2,2′,7,7′‐tetrakis(N,N‐di(4‐methoxyphenyl)amino)−9,9′‐spirobifluorene (spiro‐OMeTAD) as hole transporting material (HTM). In this work, for the first time the effect of aging the typical n‐i‐p PSCs employing nickel phthalocyanine (coded as Bis‐PF‐Ni) solely as dopant‐free HTM is investigated and as an additive in spiro‐OMeTAD solution. This study reveals that the prolong aging of these devices at dry air condition (RH = 2%, 25 °C) is beneficial for the improvement of their performances. Various bulk and surface characterization techniques are utilized to understand the factors behind the spontaneous efficiency enhancement of the devices after storage. As a result, the changes in properties of the Bis‐PF‐Ni layer are observed and at perovskite/Bis‐PF‐Ni interface, which ultimately improves the charge transport and reduces non‐radiative recombination. In addition, the devices with Bis‐PF‐Ni HTM reveal enhanced long‐term ambient and thermal stability compared to the PSCs based on doped spiro‐OMeTAD. [ABSTRACT FROM AUTHOR]

While operational stability has evolved to be the primary issue for the practical applications of perovskite solar cells (PSCs), the understanding of the origins of device degradation is still limited. Hysteresis is known as a unique and significant feature of PSCs. The hysteresis behavior of the current density-voltage (J–V) curves, governed by the interaction between the evolving ion-induced electric field and the carrier transport/recombination, offers rich and important information about the physical properties of the device. Herein, we propose to establish hysteresis as a diagnostic key to unveil and remedy degradation issues with device physics. With a custom-made ion-incorporated drift-diffusion simulator, we comprehensively investigate the relations between characteristic J–V hysteresis features and critical device issues such as bulk and surface defects, and low mobility of each layer in the PSCs. Ultimately, we derive a fundamental understanding and unveil the origins of the device degradation during the continuous operation of PSCs. This work therefore offers a new way to address and optimize PSC operational stability. The understanding of the origins of device degradation of perovskite solar cells remains limited. Here, the authors establish hysteresis as a diagnostic key to unveil and remedy degradation issues and investigate the relations between characteristic J-V hysteresis features and device deficiencies. [ABSTRACT FROM AUTHOR]

Over the last ten years, there has been a remarkable enhancement in the power conversion efficiency (PCE) of perovskite solar cells (PSCs), with poly (3,4-ethylenedioxythiohene):poly (styrenesulfonate) (PEDOT:PSS) emerging as a prevalent choice for the hole transport layer (HTL). Nevertheless, the evolution of the widely utilized PEDOT:PSS HTL has not kept pace with the swift advancements in PSC technology, attributed to its suboptimal electrical conductivity, acidic nature, and inadequate electron-blocking performance. This study presents a novel approach to enhance the HTL by introducing molybdenum oxide (MoO3) into the PEDOT:PSS, leveraging the conductivity and solution processing compatibility of MoO3. Two methods for MoO3 integration were explored: an ammonium molybdate tetrahydrate (AMT) precursor and the direct addition of MoO3 nanoparticles. The carrier dynamics of PSCs modified by MoO3 are significantly optimized. Therefore, the PCE of the device modified by AMT and molybdenum oxide is increased to 18.23 and 19.64%, respectively, and the stability of the device is also improved. This study emphasizes the potential of MoO3 in contributing to the development of more efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

CsGeI2Br-based perovskites, with their favorable band gap and high absorption coefficient, are promising candidates for the development of efficient lead-free perovskite solar cells (PSCs). However, bulk and interfacial carrier non-radiative recombination losses hinder the further improvement of power conversion efficiency and stability in PSCs. To overcome this challenge, the photovoltaic potential of the device is unlocked by optimizing the optical and electronic parameters through rigorous numerical simulation, which include tuning perovskite thickness, bulk defect density, and series and shunt resistance. Additionally, to make the simulation data as realistic as possible, recombination processes, such as Auger recombination, must be considered. In this simulation, when the Auger capture coefficient is increased to 10−29 cm6 s−1, the efficiency drops from 31.62% (without taking Auger recombination into account) to 29.10%. Since Auger recombination is unavoidable in experiments, carrier losses due to Auger recombination should be included in the analysis of the efficiency limit to avoid significantly overestimating the simulated device performance. Therefore, this paper provides valuable insights for designing realistic and efficient lead-free PSCs. [ABSTRACT FROM AUTHOR]

Temperature fluctuations induced by mountain waves can play a crucial role in the formation of polar stratospheric clouds (PSCs). In particular, the cold phase of the waves can lower local temperatures sufficiently to trigger PSC formation, even when large-scale background temperatures are too high. To provide new quantitative constraints on the relevance of this effect, this study analyzes a decade (2002–2012) of ice PSC detections obtained from Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) measurements and ERA5 data in the polar winter lower stratosphere. In the MIPAS observations, we find that approximately 52 % of the Arctic ice PSCs and 26 % of the Antarctic ice PSCs are detected at temperatures above the local Tice. Ice PSCs above Tice are concentrated around mountainous regions and their downwind directions. A backward-trajectory analysis is performed to investigate the temperature history of each ice PSC observation. The cumulative fraction of ice PSCs above Tice increases as the trajectory gets closer to the observation point. The most significant change in the fraction of ice PSCs above Tice occurs within the 6 h preceding the observations. At the observation point, the mean fractions of ice PSCs above Tice , taking into account temperature fluctuations along the backward trajectory, are 33 % in the Arctic and 9 % in the Antarctic. The results provide a quantitative assessment of the occurrence of ice PSCs above Tice in connection with orographic waves. Additionally, the observational statistics presented can be utilized for comparison with chemistry climate simulations. [ABSTRACT FROM AUTHOR]

Preoptimizing perovskite films may generally improve the performance of the final perovskite solar cells (PSCs). However, the research on whether the film optimization fully contributes to the enhancement of the final PSCs has been long neglected. We demonstrated that the preparation of metal electrodes by high-vacuum thermal evaporation, an unavoidable step in almost all device fabrication processes, will damage the surface of perovskite films, resulting in component escape, defect density rebound, carrier extraction barrier, and film stability deterioration. Therefore, the prepared perovskite film and the final film actually working in devices are not exactly the same, and the contribution of film optimization to the device improvement was weakened. We designed a bilayer structure composed of graphene oxide and graphite flakes to eliminate the unwanted film inconsistencies and thus save the film optimization loss. Therefore, the efficient PSCs with power conversion efficiency of 25.55% were obtained, which demonstrated negligible photovoltaic performance loss after operating for 2000 hours. [ABSTRACT FROM AUTHOR]

The stability issue of perovskite solar cells (PSCs) has long been of concern to researchers. Poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is commonly used as a hole transport layer (HTL) in the inverted PSCs to achieve efficient and stable performance. However, PEDOT:PSS can corrode ITO, affecting device efficiency. Moreover, the hydrophilic nature of PEDOT:PSS compromises device stability. In this work, Poly (3-hexylthiophene-2,5-diyl) (P3HT), known for its good hydrophobicity, was used to modify the surface of PEDOT:PSS, reducing its water absorption and thereby enhancing the efficiency and stability of PSCs. The results reveal that incorporating P3HT effectively enhances the hydrophobicity of PEDOT:PSS. Furthermore, it fosters the development of large-grain perovskite film on the PEDOT:PSS/P3HT bilayer. This enhancement leads to a power conversion efficiency (PCE) of 19.78% for PSCs, with an increase by 16% than that of reference cells (17.04% of PCE). Following a duration of 1000 h, the PCE for the device modified with P3HT remains above 90%, while the PCE of the reference device is below 70%. These findings suggest that using P3HT in conjunction with PEDOT:PSS as a bilayer HTL can concurrently and proficiently improve the efficiency and stability of PSCs. [ABSTRACT FROM AUTHOR]

Lithium salt-doped spiro-OMeTAD is widely used as a hole-transport layer (HTL) for high-efficiency n-i-p perovskite solar cells (PSCs), but unfortunately facing awkward instability for commercialization arising from the intrinsic Li+ migration and hygroscopicity. We herein demonstrate a superoxide radicals (•O2−) derived HTL of metal-free spiro-OMeTAD with remarkable capability of avoiding the conventional tedious oxidation treatment in air for highly stable PSCs. Present work explores the employing of variant-valence Eu(TFSI)2 salts that could generate •O2− for facile and adequate pre-oxidation of spiro-OMeTAD, resulting in the HTL with dramatically increased conductivity and work function. Comparing to devices adopting HTL with LiTFSI doping, the •O2−-derived spiro-OMeTAD increases the PSCs efficiency up to 25.45% and 20.76% for 0.05 cm2 active area and 6 × 6 cm2 module, respectively. State-of-art PSCs employing such metal-free HTLs are also demonstrated to show much-improved environmental stability even under harsh conditions, e.g., maintaining over 90% of their initial efficiency after 1000 h of operation at the maximum power point and after 80 light-thermal cycles under simulated low earth orbit conditions, respectively, indicating the potentials of developing metal-free spiro-OMeTAD for low-cost and shortened processing of perovskite photovoltaics. The migration and hygroscopicity of lithium salt in doped spiro-OMeTAD hampers the device efficiency of perovskite solar cells. Here, the authors employ Eu(TFSI)2 salts to generate superoxide radical for facile pre-oxidation, achieving enhanced efficiency and stability of solar cells and modules. [ABSTRACT FROM AUTHOR]

The trap states at both the upper and bottom interfaces of perovskite layers significantly impact non‐radiative carrier recombination. The widely used solvent‐based passivation methods result in the disordered distribution of surface components, posing challenges for the commercial application of large‐area perovskite solar cells (PSCs). To address this issue, a novel NH3 gas‐assisted all‐inorganic dual‐interfaces passivation strategy is proposed. Through the gas treatment of the perovskite surface, NH3 molecules significantly enhanced the iodine vacancy formation energy (1.54 eV) and bonded with uncoordinated Pb2+ to achieve non‐destructive passivation. Meanwhile, the reduction of the film defect states is accompanied by a decrease in the work function, which promotes carrier transport between the interface. Further, a stable passivation layer is constructed to manage the bottom interfacial defects using inorganic potassium tripolyphosphate (PT), whose ─P═O group effectively mitigated the charged defects and lowered the carrier transport barriers and nucleation barriers of PVK, while the gradient distribution of K+ improved the crystalline quality of PVK film. Based on the dual‐interface synergistic effect, the optimal MA‐contained PSCs with an effective area of 0.1 cm2 achieved an efficiency of 24.51% and can maintain 90% of the initial value after aging (10−20% RH and 20 °C) for 2000 h. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are considered the most promising photovoltaic devices to replace silicon-based solar cells because of their low preparation cost and high photoelectric conversion efficiency (PCE). Reducing defects in perovskite films is an effective means to improve the efficiency of PSCs. In this paper, a lead chelator was selected and mixed into hole transport layers (HTLs) to design and prepare mesoporous PSCs with the structure of ITO/PTAA(BCP)/Al2O3/PVK/PCBM/BCP/Ag, and its modification effect on the buried interface at the bottom of the perovskite layer in the mesoporous structure was explored. The experimental results show that in the presence of mesoporous alumina, the lead chelator can still play a role in modifying the bottom of the perovskite film. The use of lead chelator as passivation material added to the HTL can effectively reduce the residue of dimethyl sulfoxide (DMSO) and decrease the defects at the bottom of the perovskite film, which dramatically improves the device performance. The PCE of the device is increased from 18.03% to 20.78%, which is an increase of 15%. The work in this paper provides an effective method to enhance the performance of PSCs. [ABSTRACT FROM AUTHOR]

Polar stratospheric clouds (PSCs) play a crucial role in ozone depletion in the polar stratosphere. In this study, the space-based PSCs record from CALISPO and an offline three-dimensional chemical transport model (SLIMCAT) are used to analyze the PSCs in the Arctic and the Antarctic for the period 2006−2021. Observations indicate that the seasonal evolution of the Antarctic PSC area is similar from year to year. In contrast, the Arctic PSCs show large differences in seasonal variations of coverage and duration in different years. The SLIMCAT simulations effectively capture the seasonal and interannual variations of PSCs. However, the simulated PSC areas are larger than CALIPSO observations, which can be attributed to the relatively high instrumental detection threshold of CALIPSO. SLIMCAT can capture the zonal asymmetry of PSCs in both the Antarctic and Arctic, and it can reproduce a more accurate spatial distribution of PSCs when the PSC coverage area is larger. In addition, accurate simulation of HNO3 is important for PSC simulation. Because the simulation of denitrification processes is poor in SLIMCAT, which uses the thermodynamic equilibrium PSC scheme, the PSCs modeled by SLIMCAT are located at higher altitudes compared to the observation in the Antarctic, where the denitrification processes are strong. In contrast, for ice PSCs of which HNO3 is not required in calculations and the Arctic where denitrification is weak, the simulated PSC at different altitudes closely matches the observations. [ABSTRACT FROM AUTHOR]

This study presents a new approach for Maximum Power Point Tracking (MPPT) by combining the honey badger algorithm (HBA) with a Genetic Algorithm (GA). The integration aims to optimize photovoltaic (PV) system performance in partial shading conditions (PSCs). Initially, the HBA is utilized to explore extensively and identify potential solutions while avoiding local optima. If necessary, the GA is then employed to escape local optima through selection, crossover, and mutation operations. On average, this proposed method has a 40% improvement in tracking time and 0.77% in efficiency compared with the HBA. In a dynamic case, the proposed method achieves a 4.81% improvement compared to HBA. [ABSTRACT FROM AUTHOR]

Pancreatic fibrosis (PF) is primarily characterized by aberrant production and degradation modes of extracellular matrix (ECM) components, resulting from the activation of pancreatic stellate cells (PSCs) and the pathological cross‐linking of ECM mediated by lysyl oxidase (LOX) family members. The excessively deposited ECM increases matrix stiffness, and the over‐accumulated reactive oxygen species (ROS) induces oxidative stress, which further stimulates the continuous activation of PSCs and advancing PF; challenging the strategy toward normalizing ECM homeostasis for the regression of PF. Herein, ROS‐responsive and Vitamin A (VA) decorated micelles (named LR‐SSVA) to reverse the imbalanced ECM homeostasis for ameliorating PF are designed and synthesized. Specifically, LR‐SSVA selectively targets PSCs via VA, thereby effectively delivering siLOXL1 and resveratrol (RES) into the pancreas. The ROS‐responsive released RES inhibits the overproduction of ECM by eliminating ROS and inactivating PSCs, meanwhile, the decreased expression of LOXL1 ameliorates the cross‐linked collagen for easier degradation by collagenase which jointly normalizes ECM homeostasis and alleviates PF. This research shows that LR‐SSVA is a safe and efficient ROS‐response and PSC‐targeted drug‐delivery system for ECM normalization, which will propose an innovative and ideal platform for the reversal of PF. [ABSTRACT FROM AUTHOR]

Inspired by nature, intelligent self‐healing materials have recently been exploited also in the field of photovoltaics to mimic natural systems achieving self‐repairing. The past decade has witnessed perovskite solar cells (PSCs) skyrocketing to a certified power conversion efficiency of 26.1%. However, their intrinsic instability, when exposing to moisture, high temperature, and continuous illumination, hampers their commercial development for a long‐term use in ambient operating conditions. Therefore, the use of smart self‐healing materials, based on self‐assembling properties and dynamic interactions, empowers PSCs with self‐recovery abilities to reinforce their pivotal role as efficient photovoltaic devices and encourage their exploitation in the market. Herein, the current progress in self‐healing perovskite materials with a special focus on self‐recovery after moisture exposure or mechanical damage with the aim to provide a valuable insight for research on this topic to accelerate the PSC commercialization process is highlighted. [ABSTRACT FROM AUTHOR]

The primary reason for the decrease in power output from the PV array is partial shading. During partial shading conditions (PSCs) PV modules experience a mismatch in current and voltage generated. Also, the power voltage (P–V) characteristics of the PV array possess multiple peaks under PSCs. To mitigate the effects caused by PSCs, the configuration of the PV array is the finest solution. This paper proposes a novel Reduced Cross Tied (RCT) configuration to enhance maximum power output from a symmetrical PV array under PSCs. The RCT configuration has fewer cross-ties compared to the TCT configuration and is applicable to a square array of any size. The proposed RCT configuration along with conventional configurations such as Total Cross Tied (TCT), Series–Parallel, Bridge-Link, and Honey-Comb are validated in simulation and hardware for 7 × 7 and 8 × 8 symmetrical PV arrays under Short and Narrow (SN), Short and Wide (SW), Long and Narrow (LN) and Long and Wide (LW) shading patterns. A comparative analysis is done between the proposed configuration and conventional configurations in terms of mismatch loss (ML), fill factor, efficiency (η ), Wiring Loss, and Global Maximum PowerPoint (GMPP). The proposed RCT configuration is able to achieve GMPP equal to the TCT configuration under the LN shading pattern and on par with the TCT configuration under SN, SW, and LW shading patterns. RCT-configured PV array possesses a minimum reduction of 25% in wiring loss for any array size. RCT configuration applies to a square array of any size.The results replicate the efficacy of the proposed RCT configuration compared to existing configurations. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are currently demonstrating tremendous potential in terms of straightforward processing, a plentiful supply of materials, and easy architectural integration, as well as high power conversion efficiency (PCE). However, the elemental composition of the widely utilized organic–inorganic halide perovskites (OIHPs) contains the hazardous lead (Pb). The presence of Pb in the PSCs is problematic because of its toxicity which may slow down or even impede the pace of commercialization. As a backup option, the scientific community has been looking for non-toxic/less-toxic elements that can replace Pb in OIHPs. Despite not yet matching the impressive results of Pb-containing OIHPs, the community is paying close attention to Pb-free materials and has seen some encouraging findings. This review evaluates the Pb-replacement with suitable elements and scrutinizes the desirable optoelectronic features of such elements in OIHPs. The fundamental features of Pb-free OIHPs together with their photovoltaic performance in the PSCs are evaluated in details. Finally, we sum up the current challenges and potential opportunities for the Pb-free OIHPs and their devices. [ABSTRACT FROM AUTHOR]

Over the last decade, perovskite solar cells (PSCs) have drawn extensive attention owing to their high power conversion efficiency (single junction: 26.1%, perovskite/silicon tandem: 33.9%) and low fabrication cost. However, the short lifespan of PSCs with initial efficiency still blocks their practical applications. This operational instability may originate from the intrinsic and extrinsic degradation of materials or devices. Although the lifetime of PSCs has been prolonged through component, crystal, defect, interface, encapsulation engineering, and so on, the systematic analysis of failure regularity for PSCs from the perspective of materials and devices against multiple operating stressors is indispensable. In this review, we start with elaboration of the predominant degradation pathways and mechanism for PSCs under working stressors. Then the strategies for improving long‐term durability with respect to fundamental materials, interface designs, and device encapsulation have been summarized. Meanwhile, the key results have been discussed to understand the limitation of assessing PSCs stability, and the potential applications in indoor photovoltaics and wearable electronics are demonstrated. Finally, promising proposals, encompassing material processing, film formation, interface strengthening, structure designing, and device encapsulation, are provided to improve the operational stability of PSCs and promote their commercialization. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are gaining popularity due to their high efficiency and low-cost fabrication. In recent decades, noticeable research efforts have been devoted to improving the stability of these cells under ambient conditions. Moreover, researchers are exploring new materials and fabrication techniques to enhance the performance of PSCs under various environmental conditions. The mechanical stability of flexible PSCs is another area of research that has gained significant attention. The latest research also focuses on developing tin-based PSCs that can overcome the challenges associated with lead-based perovskites. This review article provides a comprehensive overview of the latest advances in materials, fabrication techniques, and stability enhancement strategies for PSCs. It discusses the recent progress in perovskite crystal structure engineering, device construction, and fabrication procedures that has led to significant improvements in the photo conversion efficiency of these solar devices. The article also highlights the challenges associated with PSCs such as their poor stability under ambient conditions and discusses various strategies employed to enhance their stability. These strategies include the use of novel materials for charge transport layers and encapsulation techniques to protect PSCs from moisture and oxygen. Finally, this article provides a critical assessment of the current state of the art in PSC research and discusses future prospects for this technology. This review concludes that PSCs have great potential as a low-cost alternative to conventional silicon-based solar cells but require further research to improve their stability under ambient conditions in view of their definitive commercialization. [ABSTRACT FROM AUTHOR]

Ever since self-assembled monolayers (SAMs) were adopted as hole-transporting layers (HTL) for perovskite solar cells (PSCs), numerous SAMs for HTL have been synthesized and reported. SAMs offer several unique advantages including relatively simple synthesis, straightforward molecular engineering, effective surface modification using small amounts of molecules, and suitability for large-area device fabrication. In this review, we discuss recent developments of SAM-based hole-transporting materials (HTMs) for PSCs. Notably, in this article, SAM-based HTMs have been categorized by similarity of synthesis to provide general information for building a SAM structure. SAMs are composed of head, linker, and anchoring groups, and the selection of anchoring groups is key to design the synthetic procedure of SAM-based HTMs. In addition, the working mechanism of SAM-based HTMs has been visualized and explained to provide inspiration for finding new head and anchoring groups that have not yet been explored. Furthermore, both photovoltaic properties and device stabilities have been discussed and summarized, expanding reader's understanding of the relationship between the structure and performance of SAMs-based PSCs. [ABSTRACT FROM AUTHOR]

Tin (Sn)‐containing perovskite solar cells (PSCs) have gained significant attention in the field of perovskite optoelectronics due to lower toxicity than their lead‐based counterparts and their potential for tandem applications. However, the lack of stability is a major concern that hampers their development. To achieve the long‐term stability of Sn‐containing PSCs, it is crucial to have a clear and comprehensive understanding of the degradation mechanisms of Sn‐containing perovskites and develop mitigation strategies. This review provides a compendious overview of degradation pathways observed in Sn‐containing perovskites, attributing to intrinsic factors related to the materials themselves and environmental factors such as light, heat, moisture, oxygen, and their combined effects. The impact of interface and electrode materials on the stability of Sn‐containing PSCs is also discussed. Additionally, various strategies to mitigate the instability issue of Sn‐containing PSCs are summarized. Lastly, the challenges and prospects for achieving durable Sn‐containing PSCs are presented. [ABSTRACT FROM AUTHOR]

Further improvement of the performance and stability of inverted perovskite solar cells (PSCs) is necessary for commercialization. Here, ferrocene derivative dibenzoylferrocene (DBzFe) is used as an additive to enhance the performance and stability of MA‐ and Br‐ free PSCs. The results show that the introduction of DBzFe not only passivates the defects in the film but also inhibits the ion migration in the film. The final device achieves a power conversion efficiency (PCE) of 23.53%, which is one of the highest efficiencies currently based on self‐assembled monolayers (SAMs). Moreover, it maintains more than 96.4% of the original efficiency when running continuously for 400 h at the maximum power point. [ABSTRACT FROM AUTHOR]

[Display omitted] The efficiency and durability of perovskite solar cells (PSCs) are closely related to the property and stability of each functional layer involved in device. Owing to the excellent hole transport properties, the additive-doped Spiro-OMeTAD (2,2′,7,7′-tetrakis (N, N -di-p-methoxyphenylamine) 9,9′-spirobifluorene) has become an excellent hole-transporting material for obtaining highly efficient PSCs. However, the hygroscopic nature of additives and the pinholes caused by poor film-forming capability inevitably impair the performance and long-term stability of Spiro-OMeTAD and the resulting PSCs. In this study, the hydrophobic polymer polystyrene (PS) was incorporated to improve the hydrophobicity and film-forming capability of the additive-doped Spiro-OMeTAD films. Based on the PS-modified Spiro-OMeTAD and carbon electrodes, the derived planar carbon-based PSCs exhibited significantly enhanced long-term stability, which can maintain 92% of its initial efficiency after aging for 2500 h under ambient atmosphere without encapsulation. In addition, the PS-modified Spiro-OMeTAD exhibited improved morphology with reduced pinholes, contributing to significantly enhanced interfacial carrier transport. Finally, a champion power conversion efficiency of 21.06% was obtained, which is one of the highest efficiencies reported for the planar carbon-based PSCs to date. [ABSTRACT FROM AUTHOR]

Many loss processes in perovskite solar cells (PSCs) take place at interfaces. One effective mitigation strategy is introducing carbon derivatives at the interface of the charge transport layers with the halide perovskite absorber and/or with the contacts. In this work, single-walled carbon nanotubes are incorporated into the hole transporting material (HTM), either as composites or as a separate layer on top of the HTM. Both organic and inorganic hole transport materials are studied to validate this approach for different types of HTMs. It is shown that the CNTs facilitate charge transport from perovskite to the back contact, regardless of the HTM used. The use of CNTs results in an increase in a significant increase in short circuit current and power conversion efficiency. This study illustrates how SWCNTs can be utilised to improve the properties of a wide range of HTMs, which will pave the way for more efficient and PSCs. [ABSTRACT FROM AUTHOR]

The effect of moisture and heat are important challenges in perovskite solar cells (PSCs). Herein we studied the performance of triple-cation PSCs in different operating environmental conditions. Humidified cells exhibited a hopeful character by increasing the open-circuit voltage (VOC) and short-circuit current density (JSC) to 940 mV and 22.85 mA cm−2 with a power conversion efficiency (PCE) of 14.34%. In addition, further analyses showed that hysteresis index and charge transfer resistance decrease down to 0.4% and 1.67 kΩ. The origin of superior stability is ion segregation to the interface, which removes the antisite defect states. Finally, the effect of operating temperature and trap density on structure and performance was also studied systematically. [ABSTRACT FROM AUTHOR]

Age‐induced degeneration of the neuromuscular junction (NMJ) is associated with motor dysfunction and muscle atrophy. While the impact of aging on the NMJ presynapse and postsynapse is well‐documented, little is known about the changes perisynaptic Schwann cells (PSCs), the synaptic glia of the NMJ, undergo during aging. Here, we examined PSCs in young, middle‐aged, and old mice in three muscles with different susceptibility to aging. Using light and electron microscopy, we found that PSCs acquire age‐associated cellular features either prior to or at the same time as the onset of NMJ degeneration. Notably, we found that aged PSCs fail to completely cap the NMJ even though they are more abundant in old compared with young mice. We also found that aging PSCs form processes that either intrude into the synaptic cleft or guide axonal sprouts to innervate other NMJs. We next profiled the transcriptome of PSCs and other Schwann cells (SCs) to identify mechanisms altered in aged PSCs. This analysis revealed that aged PSCs acquire a transcriptional pattern previously shown to promote phagocytosis that is absent in other SCs. It also showed that aged PSCs upregulate unique pro‐inflammatory molecules compared to other aged SCs. Interestingly, neither synaptogenesis genes nor genes that are typically upregulated by repair SCs were induced in aged PSCs or other SCs. These findings provide insights into cellular and molecular mechanisms that could be targeted in PSCs to stave off the deleterious effects of aging on NMJs. [ABSTRACT FROM AUTHOR]

The stability and durability of perovskite solar cells (PSCs) are two main challenges retarding their industrial commercialization. The encapsulation of PSCs is a critical process that improves the stability of PSC devices for practical applications, and intrinsic stability improvement relies on materials optimization. Among all encapsulation materials, UV-curable resins are promising materials for PSC encapsulation due to their short curing time, low shrinkage, and good adhesion to various substrates. In this review, the requirements for PSC encapsulation materials and the advantages of UV-curable resins are firstly critically assessed based on a discussion of the PSC degradation mechanism. Recent advances in improving the encapsulation performance are reviewed from the perspectives of molecular modification, encapsulation materials, and corresponding architecture design while highlighting excellent representative works. Finally, the concluding remarks summarize promising research directions and remaining challenges for the use of UV-curable resins in encapsulation. Potential solutions to current challenges are proposed to inspire future work devoted to transitioning PSCs from the lab to practical application. [ABSTRACT FROM AUTHOR]

A photovoltaic (PV) cell is the smallest unit in an array that exhibits nonlinear characteristic curves. To gather the maximum amount of energy from a PV array under partial shading conditions (PSCs), it is necessary to follow the largest peak in the power–voltage (P–V) curve. PV cells are partially or totally shaded due to atmospheric conditions, which show multiple peaks in the PV curve. To overcome the losses occurring due to PSCs, PV array reconfiguration action is advisable. The authors of this work proposed a novel 5×5 $5\times 5$ quad‐tied PV array configuration and compared its performance to that of other current configurations such as series‐parallel, total‐cross tied, and others in terms of global maximum power point tracking, mismatch loss, fill factor, and efficiency. The MATLAB/Simulink 2020a platform was used to generate PV array curves under various shading conditions. [ABSTRACT FROM AUTHOR]

The defects within perovskite films are the fatal roadblock limiting the performance of perovskite solar cells (PSCs). Herein, we develop a patching strategy to obtain high‐quality perovskite film using bifunctional trifluorophenylacetic acid (TFPA). Theoretical calculation and experiments reveal that the –COOH groups in TFPA effectively passivate the deep‐energy‐level defects of perovskite by combining with Pb clusters on the perovskite grain surfaces to enhance the efficiency of PSCs, and hydrophobic benzene groups containing fluorine in TFPA are exposed to improve the stability of PSCs. The power conversion efficiency (PCE) of PSCs with TFPA is enhanced from 22.95% to 24.56%. Most importantly, we successfully fabricated flexible PSCs using TFPA with the high PCE of 22.65%. The devices with TFPA maintain 93.22% of the initial efficiency MPP under continuous irradiation for 10.5 h, while the devices without TFPA only retain 82.22% of the initial efficiency under the same conditions for just 5 h. Meanwhile, the unsealed devices with TFPA hold 93.59% of the initial efficiency when stored in air for 3912 h. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have exhibited tremendous potential in photovoltaic fields owing to their appreciable performance and simple fabrication. Nevertheless, device performances are still required to be further improved before commercial applications. As one‐dimensional materials, carbon nanotubes (CNTs) have been utilized to regulate stability and efficiency of PSCs because of their excellent chemical stability, flexibility, as well as tunable optical and electrical characteristics. In this review, we comprehensively summarize various functions of CNTs in PSCs, such as transparent electrodes, hole/electron‐transport layers, counter electrodes, perovskite additives, and interlayers. Additionally, applications of CNTs toward the advancement of flexible and semitransparent PSCs are provided. Finally, we preview the challenges and research interests of using CNTs in high‐efficiency and stable perovskite devices. [ABSTRACT FROM AUTHOR]

To find a suitable medium for muscle satellite cells of Larimichthys crocea, herein, the effect of different basal media and coating materials on the proliferation of piscine satellite cells (PSCs) was explored. Firstly, two basal media, namely F10 and DMEM/F12, were selected as experimental materials, and high-sugar DMEM was the main basal culture medium used with fish muscle cells as a control. The results showed that the PSCs proliferated better in F10 than in DMEM/F12 or DMEM. Secondly, the effects of rat tail collagen, polylysine and matrix coatings, as compared with no coating, on the proliferation and later differentiation of PSCs were also investigated. Our results indicated that there was no significant difference between coating and no coating on the proliferation of PSCs in the F10-based medium. Meanwhile, it was found that the myotubes were washed out, and only those under matrix-coated conditions remained intact in the process of differentiation. The results also suggested that PSCs could still differentiate into myotubes without their stemness being affected after proliferation in the F10-based medium. Hence, this study identified an efficient proliferation medium based on F10 basal medium that could shorten the culture time and maintain the stemness of PSCs, thus providing a basis for large-scale cell expansion and cell-culture-based meat production in the future. [ABSTRACT FROM AUTHOR]

Human pluripotent stem cells (PSCs) hold a great promise for promoting regenerative medical therapies due to their ability to generate multiple mature cell types and for their high expansion potential. However, cell therapies require large numbers of cells to achieve desired therapeutic effects, and traditional two-dimensional static culture methods cannot meet the required production demand for cellular therapies. One solution to this problem is scaling up expansion of PSCs in bioreactors using culture strategies such as growing cells on microcarriers or as aggregates in suspension culture. In this study, we directly compared PSC expansion and quality parameters in microcarrier- and aggregate-cultures grown in single-use vertical-wheel bioreactors. We showed comparable expansion of cells on microcarriers and as aggregates by day 6 with a cell density reaching 2.2 × 106 cells/mL and 1.8 × 106 cells/mL and a fold-expansion of 22- and 18-fold, respectively. PSCs cultured on microcarriers and as aggregates were comparable with parallel two-dimensional cultures and with each other in terms of pluripotency marker expression and retention of other pluripotency characteristics as well as differentiation potential into three germ layers, neural precursor cells and cardiomyocytes. Our study did not demonstrate a clear advantage between the two three-dimensional methods for the quality parameters assessed. This analysis adds support to the use of bioreactor systems for large scale expansion of PSCs, demonstrating that the cells retain key characteristics of PSCs and differentiation potential in suspension culture. [ABSTRACT FROM AUTHOR]

This paper applies the innovative idea of DLCI to PV array reconfiguration under various PSCs to capture the maximum output power of a PV generation system. DLCI is a hybrid algorithm that integrates multiple meta-heuristic algorithms. Through the competition and cooperation of the search mechanisms of different metaheuristic algorithms, the local exploration and global development of the algorithm can be effectively improved to avoid power mismatch of the PV system caused by the algorithm falling into a local optimum. A series of discrete operations are performed on DLCI to solve the discrete optimization problem of PV array reconfiguration. Two structures (DLCI-I and DLCI-II) are designed to verify the effect of increasing the number of sub-optimizers on the optimized performance of DLCI by simulation based on 10 cases of PSCs. The simulation shows that the increase of the number of sub-optimizers only gives a relatively small improvement on the DLCI optimization performance. DLCI has a significant effect on the reduction in the number of power peaks caused by PSC. The PV array-based reconstruction system of DLCI-II is reduced by 4.05%, 1.88%, 1.68%, 0.99% and 3.39%, when compared to the secondary optimization algorithms. [ABSTRACT FROM AUTHOR]

Controlling the aggregation of small-molecule acceptors (SMAs) is essential to obtain an optimal morphology and to improve the photovoltaic performance of polymer solar cells (PSCs). However, reducing intermolecular aggregation of SMAs is usually accompanied by the disruption of compact molecular packing thereby leading to their decreased electron mobilities. Here, two novel M-series SMAs (MD1T and MD2T) based on ladder-type heterononacenes with neighboring side-chains separated by one or two thiophene rings are designed and synthesized. It is found that shortening the spacing of the neighboring side-chains of the SMAs can greatly alleviate the intermolecular aggregation and alter the molecular orientation from bimodal edge-on/face-on to predominant face-on while maintaining the compact molecular packing. As a result, a more favorable morphology with smaller domain sizes is formed for the MD1T-based blend films, which greatly improves the charge generation and charge transport for the corresponding PSCs. The best-performing MD1T-based device affords an efficiency of 12.43%, over seven times higher than that of the MD2T-based device. This work reveals the importance of the spacing between the neighboring side-chains in modulating the molecular aggregation and active layer morphology, and the obtained structure-performance relationships shall provide important guidance for designing highly efficient SMAs. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are solar cells that have intriguing characteristics such as environmental friendliness and the capability for high power conversion efficiency, which have attracted study from both scientific investigation and analytical standpoints. However, lead toxicity has become a significant barrier to the widespread use of PSCs. Due to the serious environmental implications of lead, an environmentally compatible perovskite is required. Tin-based perovskite has a considerable impact, showing that it is a good hole extraction material with good mobility and low effective mass. In this study, we explore the impacts of perovskite and hole transporting layer (HTL) thickness, and intensity of light limitations, in inverted PSCs based on the structure of FTO/NiO/MAPbI3/ZnO/Ag and FTO/NiO/MASnI3/ZnO/Ag incorporating GPVDM (General-purpose Photovoltaic Device Model) to evaluate if MASnI3 is a viable substitute to MAPbI3. From the simulation results, the optimized parameters obtained for PCSs under 1 sun incorporating MASnI3 were 27.97%, 0.88 a.u., 0.92 V, and 34.45 mA/cm². Instead, the optimized parameters obtained for PCSs incorporating MAPbI3 were 24.94%, 0.88 a.u., 0.90 V, and 31.03 mA/cm². The thickness of the film of both PSC architectures was optimized to provide the best suitable result. The findings show that MASnI3 is employed as a promising perovskite layer in PSCs instead of MAPbI3. [ABSTRACT FROM AUTHOR]

Highlights: The fundamental properties of electric dipoles and their specific roles in perovskite solar cells are discussed. Research progress of interfacial dipoles in perovskite solar cells is summarized. Challenges of deterministic characterization of electric dipoles and future perspectives are highlighted. Design and modification of interfaces have been the main strategies in developing perovskite solar cells (PSCs). Among the interfacial treatments, dipole molecules have emerged as a practical approach to improve the efficiency and stability of PSCs due to their unique and versatile abilities to control the interfacial properties. Despite extensive applications in conventional semiconductors, working principles and design of interfacial dipoles in the performance/stability enhancement of PSCs are lacking an insightful elucidation. In this review, we first discuss the fundamental properties of electric dipoles and the specific roles of interfacial dipoles in PSCs. Then we systematically summarize the recent progress of dipole materials in several key interfaces to achieve efficient and stable PSCs. In addition to such discussions, we also dive into reliable analytical techniques to support the characterization of interfacial dipoles in PSCs. Finally, we highlight future directions and potential avenues for research in the development of dipolar materials through tailored molecular designs. Our review sheds light on the importance of continued efforts in this exciting emerging field, which holds great potential for the development of high-performance and stable PSCs as commercially demanded. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have been developed rapidly in recent years because of their excellent photoelectric performance. However, interfacial non-radiative recombination hinders the improvement of device performance. The buried interface modification strategy can minimize the non-radiation recombination in the interface and can obtain the high efficiency and stability of PSCs. In this review, we introduce the device structure and the charge carrier dynamics (charge transfer, extraction, and collection) at the interface. We further summarize the main sources of non-radiative recombination at the interface, such as energy alignment mismatch and interface defects, and methods to characterize them. In contrast to the previous review of perovskite solar cells, the important roles of buried interfaces in regulating energy level alignment, passivating surface defects, modulating morphology, and so on are reviewed in detail based on the latest research, and strategies for reducing interfacial nonradiative recombination are provided. In the end, the potential development and challenges of buried interfaces for high-performance and stable PSCs are presented. [ABSTRACT FROM AUTHOR]

The aim of this work is to investigate the degradation of perovskite solar cells (PSCs) by means of impedance spectroscopy, a highly sensitive characterization technique used to establish the electrical response of a device in a nondestructive manner. In this paper, PSCs with two different electron transport layers (ETLs) are studied: PSCs with undoped SnO2 as an ETL are compared to PSCs with an ETL composed of graphene-doped SnO2 (G-SnO2). Experimental data were collected immediately after fabrication and after one week, monitoring both impedance spectroscopy and dark current-voltage (I-V) curves. It was observed that, in the case of the undoped PSCs, the degradation of the solar cells affected both the AC behavior of the devices, modifying the associated Nyquist plots, and the DC behavior, observable from the dark I-V measurements. Conversely, the solar cells with G-SnO2 showed no variation. Considering the Nyquist plots, a quantitative analysis was performed by comparing the parameters of a proper equivalent circuit model. The results were coherent with those achieved in the DC analysis, thus proving that the analysis of impedance spectra, supported with dark I-V curves, allows one to gain a deeper knowledge of the degradation phenomena of perovskite solar cells. This study opens the door for further improvement of these devices through a better understanding of their electrical behavior. [ABSTRACT FROM AUTHOR]

Oncolytic viruses (OVs) are an emerging cancer therapeutic that are intended to act by selectively targeting and lysing cancerous cells and by stimulating anti-tumour immune responses, while leaving normal cells mainly unaffected. Reovirus is a well-studied OV that is undergoing advanced clinical trials and has received FDA approval in selected circumstances. However, the mechanisms governing reoviral selectivity are not well characterised despite many years of effort, including those in our accompanying paper where we characterize pathways that do not consistently modulate reoviral cytolysis. We have earlier shown that reovirus is capable of infecting and lysing both certain types of cancer cells and also cancer stem cells, and here we demonstrate its ability to also infect and kill healthy pluripotent stem cells (PSCs). This led us to hypothesize that pathways responsible for stemness may constitute a novel route for the modulation of reoviral tropism. We find that reovirus is capable of killing both murine and human embryonic and induced pluripotent stem cells. Differentiation of PSCs alters the cells' reoviral-permissive state to a resistant one. In a breast cancer cell line that was resistant to reoviral oncolysis, induction of pluripotency programming rendered the cells permissive to cytolysis. Bioinformatic analysis indicates that expression of the Yamanaka pluripotency factors may be associated with regulating reoviral selectivity. Mechanistic insights from these studies will be useful for the advancement of reoviral oncolytic therapy. [ABSTRACT FROM AUTHOR]

Weakly supervised object detection (WSOD) in remote sensing images (RSIs) has attracted more and more attention because its training merely relies on image-level category labels, which significantly reduces the cost of manual annotation. With the exploration of WSOD, it has obtained many promising results. However, most of the WSOD methods still have two challenges. The first challenge is that the detection results of WSOD tend to locate the significant regions of the object but not the overall object. The second challenge is that the traditional pseudo-instance label assignment strategy cannot adapt to the quality distribution change of proposals during training, which is not conducive to training a high-performance detector. To tackle the first challenge, a novel high-quality seed instance mining (HSIM) module is designed to mine high-quality seed instances. Specifically, the proposal comprehensive score (PCS) that consists of the traditional proposal score (PS) and the proposal space contribution score (PSCS) is designed as a novel metric to mine seed instances, where the PS indicates the probability that a proposal pertains to a certain category and the PSCS is calculated by the spatial correlation between top-scoring proposals, which is utilized to evaluate the wholeness with which a proposal locates an object. Consequently, the high PCS will encourage the WSOD model to mine the high-quality seed instances. To tackle the second challenge, a dynamic pseudo-instance label assignment (DPILA) strategy is developed by dynamically setting the label assignment threshold to train high-quality instances. Consequently, the DPILA can better adapt the distribution change of proposals according to the dynamic threshold during training and further promote model performance. The ablation studies verify the validity of the proposed PCS and DPILA. The comparison experiments verify that our method obtains better performance than other advanced WSOD methods on two popular RSIs datasets. [ABSTRACT FROM AUTHOR]

Highlights: High quality and strongly oriented perovskite films are prepared by two step doctor blading in air. Methylammonium chloride induced low dimensional intermediate phase regulates the crystallization and orientation of the perovskite. Two step doctor bladed perovskite solar cells achieve a power conversion efficiency (PCE) of 23.14%, while 1.03 cm2 PSCs and 10.93 cm2 mini modules achieve PCEs of 21.20% and 17.54%, respectively. With the rapid rise in perovskite solar cells (PSCs) performance, it is imperative to develop scalable fabrication techniques to accelerate potential commercialization. However, the power conversion efficiencies (PCEs) of PSCs fabricated via scalable two-step sequential deposition lag far behind the state-of-the-art spin-coated ones. Herein, the additive methylammonium chloride (MACl) is introduced to modulate the crystallization and orientation of a two-step sequential doctor-bladed perovskite film in ambient conditions. MACl can significantly improve perovskite film quality and increase grain size and crystallinity, thus decreasing trap density and suppressing nonradiative recombination. Meanwhile, MACl also promotes the preferred face-up orientation of the (100) plane of perovskite film, which is more conducive to the transport and collection of carriers, thereby significantly improving the fill factor. As a result, a champion PCE of 23.14% and excellent long-term stability are achieved for PSCs based on the structure of ITO/SnO2/FA1-xMAxPb(I1-yBry)3/Spiro-OMeTAD/Ag. The superior PCEs of 21.20% and 17.54% are achieved for 1.03 cm2 PSC and 10.93 cm2 mini-module, respectively. These results represent substantial progress in large-scale two-step sequential deposition of high-performance PSCs for practical applications. [ABSTRACT FROM AUTHOR]

It is a great challenge to develop low-cost and dopant-free polymer hole-transporting materials (HTM) for PSCs, especially for efficient air-processed inverted (p-i-n) planar PSCs. A new homopolymer HTM, poly(2,7-(9,9-bis(N,N-di-p-methoxylphenyl amine)-4-phenyl))-fluorene (denoted as PFTPA), with appropriate photo-electrochemical, opto-electronic and thermal stability, was designed and synthesized in two steps to meet this challenge. By employing PFTPA as dopant-free hole-transport layer in air-processed inverted PSCs, a champion power conversion efficiency (PCE) of up to 16.82% (0.1 cm2) was achieved, much superior to that of commercial HTM PEDOT:PSS (13.8%) under the same conditions. Such a superiority is attributed to the well-aligned energy levels, improved morphology, and efficient hole-transporting, as well as hole-extraction characteristics at the perovskite/HTM interface. In particular, these PFTPA-based PSCs fabricated in the air atmosphere maintain a long-term stability of 91% under ambient air conditions for 1000 h. Finally, PFTPA as the dopant-free HTM was also fabricated the slot-die coated perovskite device through the same fabrication condition, and a maximum PCE of 13.84% was obtained. Our study demonstrated that the low-cost and facile homopolymer PFTPA as the dopant-free HTM are potential candidates for large-scale production perovskite solar cell. [ABSTRACT FROM AUTHOR]

Formed in the mid-1990s, the Popular Services Committees (PSC) in West Bank refugee camps have played a dual role: on the one hand, they are a liaison body between the camps and UNRWA and the Palestinian Authority (PA), and on the other, they perceive themselves as a political body and guardian of the right of return. In this article, Ala Alazzeh ethnographically historicizes the formation and position of the PSCs within the Palestinian political field. The author shows the role of the camp Youth Centers in the formation of PSCs, the post-Oslo tension between camp residents and the PA, and the camp residents' capitalization on the PLO's legacy and authority. He also points out the tension between self-representation of PSCs as a political body versus their de facto practice as municipallike mediators between refugee camp communities and UNRWA, and the PA. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have seen a rapid increase in power conversion efficiencies (PCEs) over just a few years and are already competing against other photovoltaic (PV) technologies. The PCE of hybrid PSCs exhibiting distinct properties has increased from 3.8% in 2009 to ≈30% in 2023, making it a strong contender for the next generation of PV devices. However, their long-term stability is a critical issue that must be addressed before these devices can be commercialised. This review begins with a discussion of the evolution of different generations of solar cells, and the following part presents details of perovskite characteristics and prospective strategies to improve their performance. Next, the relationship of stability of PSCs with different environmental conditions, including moisture, UV light, and temperature, is discussed. Besides the development of PSC–silicon tandem solar cells, an efficient way to improve PCE is also discussed. Towards the end, we discuss a novel idea of implementing PSCs with a concentrated PV application in order to achieve higher efficiency and compete with other PV technologies by catching incident high-proton density. This review offers perspectives on the future development of emerging PSC technologies in terms of device performance enhancement and improved stability, which are central to tandem and concentrated PSC technology. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted much attention due to their low-cost fabrication and high power conversion efficiency (PCE). However, the long-term stability issues of PSCs remain a significant bottleneck impeding their commercialization. Inverted PSCs with a p-i-n architecture are being actively researched due to their concurrent good stability and decent efficiency. In particular, the PCE of inverted PSCs has improved significantly in recent years and is now almost approaching that of n-i-p PSCs. This review summarizes recent progress in the development of high-efficiency inverted PSCs, including the development of perovskite compositions, fabrication methods, and counter electrode materials (CEMs). Notably, we highlight the development of charge transport materials (CTMs) and the effects of defect passivation strategies on the performance of inverted PSCs. Finally, we discuss the remaining issues and perspectives of high-efficiency inverted PSCs. Inverted perovskite solar cells (PSCs) with a p-i-n architecture are being actively researched due to their concurrent good stability and decent efficiency. In particular, the power conversion efficiency (PCE) of inverted PSCs has seen clear improvement in recent years and is now almost approaching that of n-i-p PSCs. Here, we systematically review recent progress in the development of high-efficiency inverted PSCs, and highlight the development of charge transport materials and the effects of defect passivation strategies on the performance of inverted PSCs, with the aim of providing constructive suggestions for the future development of inverted PSCs. [ABSTRACT FROM AUTHOR]

In the present paper, we analyse 11 years of lidar measurements to derive general characteristics of polar stratospheric clouds (PSCs) and to examine how mountain lee waves influence PSC properties. Measurements of PSCs were made with a backscatter lidar located in Kiruna, northern Sweden, in the lee of the Scandinavian mountain range. The statistical analysis demonstrates that nearly half of all observed PSCs consisted of nitric acid trihydrate (NAT) particles, while ice clouds accounted for only a small fraction, and the remainder consisted of supercooled ternary solution (STS) and mixtures of different compositions. Most PSCs were observed around 22 km altitude. Mountain lee waves provide a distinct influence on PSC chemical composition and cloud height distribution. Ice PSCs were about 5 times as frequent, and NAT clouds were about half as frequent under wave conditions. PSCs were on average at 2 km higher altitudes when under the influence of mountain lee waves. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) with high efficiency and low cost are being actively developed. In recent years, the role of lead-based PSCs has become very important in the solar cell industry. But its toxicity and instability present a significant challenge to the development of commercially viable products. Under such circumstances, Ti-based all-inorganic (PSC) materials are of paramount importance in the development of high-performance PSCs. This work examines the theoretical feasibility of a lead-free, environmentally friendly, and reliable Cs2TiBr6-based PSC. The analysis of various hole transport layers (HTLs) and electron transport layers (ETLs) is performed in order to select materials that would result in stronger perovskite solar cells with higher stability. The goal of this paper is to design a lead-free PSC using Cs2TiBr6 as an absorber layer in the form of Au/CuSbS2/ Cs2TiBr6/WO3/FTO. Each composite layer is optimized and analyzed through simulations utilizing SCAPS-1D software to achieve elevated performance. A maximum power-conversion efficiency of 20.40% is achieved for the proposed solar cell through optimization of the ETL, HTL, metal contact materials, defect density of the absorber and the thickness of the absorber, HTL, and FTO. These results will pave the way for developing eco-friendly and highly efficient perovskite photovoltaic devices. [ABSTRACT FROM AUTHOR]

Highlights: A graded inverted solar cell configuration is developed by hole-transport management aiming to suppress interface defects-induced non-radiative recombination for efficient hole transport. NiOx-based inverted PSCs present a power-conversion-efficiency over 23% with a high fill factor of 0.84 and open-circuit voltage of 1.162 volts, one of the best performances reported so far for 1.56-electron volt bandgap formamidinium-based triple-halide perovskites. Devices show high operational stability over 1,200 h during T90 lifetime measurement under 1-sun illumination in ambient-air conditions. NiOx-based inverted perovskite solar cells (PSCs) have presented great potential toward low-cost, highly efficient and stable next-generation photovoltaics. However, the presence of energy-level mismatch and contact-interface defects between hole-selective contacts (HSCs) and perovskite-active layer (PAL) still limits device efficiency improvement. Here, we report a graded configuration based on both interface-cascaded structures and p-type molecule-doped composites with two-/three-dimensional formamidinium-based triple-halide perovskites. We find that the interface defects-induced non-radiative recombination presented at HSCs/PAL interfaces is remarkably suppressed because of efficient hole extraction and transport. Moreover, a strong chemical interaction, halogen bonding and coordination bonding are found in the molecule-doped perovskite composites, which significantly suppress the formation of halide vacancy and parasitic metallic lead. As a result, NiOx-based inverted PSCs present a power-conversion-efficiency over 23% with a high fill factor of 0.84 and open-circuit voltage of 1.162 V, which are comparable to the best reported around 1.56-electron volt bandgap perovskites. Furthermore, devices with encapsulation present high operational stability over 1,200 h during T90 lifetime measurement (the time as a function of PCE decreases to 90% of its initial value) under 1-sun illumination in ambient-air conditions. [ABSTRACT FROM AUTHOR]

So far, single-junction flexible PSCs have been lacking in efficiency compared to rigid PSCs. Recently, > 23% have been reported. We therefore focus on understanding the differences between rigid and flexible substrates. One often neglected parameter is the different surface roughness which directly affects the perovskite film formation. Therefore, we adjust the layer thickness of SnO2 and the perovskite layers. Furthermore, we introduce a PMMA layer between the perovskite and the hole transporting material (HTM), spiro-MeOTAD, to mitigate shunting pathways. In addition, the multication perovskite Rb0.02Cs0.05FA0.77MA0.16Pb(I0.83Br0.17)3 is employed, resulting in stabilized performances of 16% for a flexible ITO substrate and 19% on a rigid ITO substrate. [ABSTRACT FROM AUTHOR]

The article proposes a new approach to maximum power point tracking (MPPT) for photovoltaic (PV) systems operating under partial shading conditions (PSCs) that improves upon the limitations of traditional methods in identifying the global maximum power (GMP), resulting in reduced system efficiency. The proposed approach uses a two-stage MPPT method that employs machine learning (ML) and terminal sliding mode control (TSMC). In the first stage, a neuro fuzzy network (NFN) is used to improve the accuracy of the reference voltage generation for MPPT, while in the second stage, a TSMC is used to track the MPP voltage using a non-inverting DC—DC buck-boost converter. The proposed method has been validated through numerical simulations and experiments, demonstrating significant enhancements in MPPT performance even under challenging scenarios. A comprehensive comparison study was conducted with two traditional MPPT algorithms, PID and P&O, which demonstrated the superiority of the proposed method in generating higher power and less control time. The proposed method generates the least power loss in both steady and dynamic states and exhibits an 8.2% higher average power and 60% less control time compared to traditional methods, indicating its superior performance. The proposed method was also found to perform well under real-world conditions and load variations, resulting in 56.1% less variability and only 2–3 W standard deviation at the GMPP. [ABSTRACT FROM AUTHOR]