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Despite remarkable progress in perovskite solar cells (PSCs), the unsatisfying stability strongly interrelated with the defect density remains the main obstacle for commercialization. Herein, a synergetic defect passivation method is judiciously designed that consists of a precursor engineering strategy based on an ionic liquid 1‐butylsulfonate‐3‐methylimidazolium dihydrogen phosphate (BMDP), and two‐stage annealing (TSA) treatment to sufficiently passivate defects and enhance performance further. It is found that the multifunctional groups from BMDP have strong chemical interactions and form chelated complexes with perovskite components thus effectively passivating the intrinsic defects. Synergized by the sequential TSA treatment, the formed hydrophobic complexes can be precisely controlled with filling along grain boundaries (GBs) and on surfaces, leading to a wrapping of perovskite grains and significant passivation of GBs. Consequently, both deep‐ and shallow‐level defects in the bulk, at GBs and surface are sufficiently passivated, resulting in a champion efficiency of 24.20%. Impressively, the resultant unencapsulated films and corresponding devices exhibit admirable stability with maintaining 83.9% of initial composition for 4000 h of aging in moist air, 81.7% original structure after continuous heating for 1600 h, and 97% initial power conversion efficiency for 1000 h under continuous illumination. This work provides an efficient strategy toward improved efficiency and stability PSCs. [ABSTRACT FROM AUTHOR]

Compared with inverted 3D perovskite solar cell (PSCs), inverted quasi-2D PSCs have advantages in device stability, but the device efficiency is still lagging behind. Constructing polymer hole-transporting materials (HTMs) with passivation functions to improve the buried interface and crystallization properties of perovskite films is one of the effective strategies to improve the performance of inverted quasi-2D PSCs. Herein, two novel side-chain functionalized polymer HTMs containing methylthio-based passivation groups are designed, named PVCz-SMeTPA and PVCz-SMeDAD, for inverted quasi-2D PSCs. Benefited from the non-conjugated flexible backbone bearing functionalized side-chain groups, the polymer HTMs exhibit excellent film-forming properties, well-matched energy levels and improved charge mobility, which facilitates the charge extraction and transport between HTM and quasi-2D perovskite layer. More importantly, by introducing methylthio units, the polymer HTMs can enhance the contact and interactions with quasi-2D perovskite, and further passivating the buried interface defects and assisting the deposition of high-quality perovskite. Due to the suppressed interfacial non-radiative recombination, the inverted quasi-2D PSCs using PVCz-SMeTPA and PVCz-SMeDAD achieve impressive power conversion efficiency (PCE) of 21.41% and 20.63% with open-circuit voltage of 1.23 and 1.22 V, respectively. Furthermore, the PVCz-SMeTPA based inverted quasi-2D PSCs also exhibits negligible hysteresis and considerably improved thermal and long-term stability. [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]

Significant advancements in perovskite solar cells (PSCs) have been driven by the engineering of the interface between perovskite absorbers and charge transport layers. Inverted PSCs offer substantial potential with their high power conversion efficiency (PCE) and enhanced compatibility for tandem solar cell applications. Conventional hole transport materials like poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and poly(triaryl amine) (PTAA) not only constrain the PSC efficiency but also elevate their fabrication costs. In the case of improving inverted structured PSCs according to the aforementioned concerns, utilizing self‐assembled monolayers (SAMs) as hole‐transporting layers has played a crucial role. However, the growth of self‐assembled monolayers on the substrates still limits the performance and reproducibility of inverted structured PSCs. In this study, the authors delve into the growth model of SAMs on different surface morphologies. Moreover, it is found that the plasma treatment can effectively regulate the surface morphologies of substrates and achieve conformal growth of SAMs. This treatment improves the uniformity and suppresses non‐radiative recombination at the interface, which leads to a PCE of 24.5% (stabilized at 23.5%) for inverted structured PSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: As the third generation new battery, the power conversion efficiency (PCE) of metal halide perovskite solar cells (PSCs) has increased from 3.8% in 2009 to 25.8% currently certified, which fully shows that they have great research value and development prospect. As one of the main components of high‐efficiency PSCs, hole transport materials (HTMs) play an important role in extracting and transporting holes and inhibiting charge recombination. However, commonly used HTMs require doping, and the hygroscopicity and corrosiveness of the dopants will destroy the stability of PSCs and hinder their commercialization. Therefore, it is of great significance to develop dopant‐free HTMs. In this review, the dopant‐free HTMs in recent six years are reviewed and summarized systematically, including organic small molecules, polymers and cross‐linkable materials. We focus on the design of the molecular cores and discuss their structure–property correlation, conductivity, and photovoltaic performance. Finally, how to design an ideal HTM is summarized. We hope that this review can provide reference for the development of low‐cost and dopant‐free HTMs to prepare efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: As the third generation new battery, the power conversion efficiency (PCE) of metal halide perovskite solar cells (PSCs) has increased from 3.8% in 2009 to 25.8% currently certified, which fully shows that they have great research value and development prospect. As one of the main components of high‐efficiency PSCs, hole transport materials (HTMs) play an important role in extracting and transporting holes and inhibiting charge recombination. However, commonly used HTMs require doping, and the hygroscopicity and corrosiveness of the dopants will destroy the stability of PSCs and hinder their commercialization. Therefore, it is of great significance to develop dopant‐free HTMs. In this review, the dopant‐free HTMs in recent six years are reviewed and summarized systematically, including organic small molecules, polymers and cross‐linkable materials. We focus on the design of the molecular cores and discuss their structure–property correlation, conductivity, and photovoltaic performance. Finally, how to design an ideal HTM is summarized. We hope that this review can provide reference for the development of low‐cost and dopant‐free HTMs to prepare efficient and stable PSCs. [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]

As the high calibre candidate of lightweight and flexible solar cells, polymer solar cells (PSCs) have made tremendous progress in recent years. However, the active photovoltaic materials in PSCs are mainly synthesized by metal-mediated coupling reaction requiring harsh reaction conditions, multiple-step synthesis, and cumbersome purification, which is not cost-efficient and may bring toxicity concerns. It is not favorable to the production of photovoltaic polymers and PSC devices on a large scale, and therefore unsuitable for the PSCs industrialization. Direct arylation coupling reaction via aromatic C—H bonds activation enables the synthesis of conjugated polymers under mild conditions and simultaneously reduces synthetic steps, difficulty, and toxic reaction byproducts. This review provides an overview of the history of preparing representative photovoltaic polymers utilized in PSCs through direct arylation reactions and discusses the activity and selectivity of C—H bonds in typical building blocks under different reaction conditions. Especially, the impact of direct arylation condition on defect formation and photovoltaic performance of the photovoltaic polymers is addressed and compared with conventional Stille coupling methods. [ABSTRACT FROM AUTHOR]

In this work, we have investigated a conjugated copolymer (CP) Poly[{9,9-dihexyl-2,7-bis(1-cyanovinylene)fluorenylene}-alt-co-{2,5-bis(N,N′-diphenylamino)-1,4-phenylene}] (PF-CN-DPD), a red-emitting OLED material as a hole-conducting material in heterojunction perovskite solar cells (PSCs). The FESEM image revealed that the solar cells had FTO substrate/compact TiO2/mesopores TiO2 (Perovskite + CP)/Spiro-OMTAD/gold layers. The concentration of perovskite and PF-CN-DPD in DMSO: DMF (8:1) solution was 1.2 M and 72.73 μM. The pure PSC (R1) produced a power conversation efficiency (PCE) of 18.84%, but when the polymer and perovskite solutions were added in 1:3 ratios (R3), the PCE changed to 15.16%, which is less than pure perovskite. But after 30 days of continuous exposure, mixed PSC (R3) PCE dropped to 9.97%, when compared to pure PSC (R1) efficiency dropped to 4.67%. PF-CN-DPD-based heterojunction PSCs showed better stability that could be attributed to the concealing (environmental and radical migration passivation) and improved hole transport due to polymer. When the polymer ratio increased in PSC (R2), the stability increased, but efficiency dropped significantly. The presence of polymer also reduces humidity-based degradation and thermal damage. This work shows that OLED materials can be repurposed as a hole transport layer in PSCs to improve their stability. It can be particularly useful in remote location lighting and sensing applications. [ABSTRACT FROM AUTHOR]

The Copper (Cu)-based perovskite materials, (CH3NH3)2CuX4 or (MA)2CuX4 with [X = Cl4, Cl2I2, and Cl2Br2] are explored for use in perovskite solar cells (PSCs). The foremost objectives of this investigation are the optimization and finding the combination of Electron Transport Layer [ETL], Perovskite Absorber Layer (PAL) and the different organic and inorganic Hole Transport Layers [HTLs] for better device performance. The impact of other important functional parameters on the performance of PSCs are also studied. These parameters are, thicknesses of PAL, operating temperature (T), series resistance (RS), and radiative recombination rate under the illuminance of AM1.5. This SCAPS-1D simulation study deduced the optimized value of the thickness for (MA)2CuCl4, (MA)2CuCl2I2 and (MA)2CuCl2Br2 based absorber layer to be 400 nm, 500 nm and 600 nm, respectively at defect density (Nt) of 1 × 1013 cm−3 and 300 K operating temperature. The optimum value of operating temperature is 300 K for all PSCs but for C60/(MA)2CuCl4/Cu2O PSC, optimum value is 320 K at 400 nm of absorber layer. With considerations of all these optimum values, the highest power conversion efficiency of 28.31% has been obtained for the PCBM/(MA)2CuCl2Br2/CuI configuration at operating temperature of 300 K. Thus, the study reveals that PCBM as ETL, while CuI and Cu2O as HTLs are most suitable for the Cu-based PSC. Based upon the comparison with experimental results, our findings are indicative of the fact that traditional charge transport materials like TiO2 and spiro-OMeTAD may not be the best choices for new lead-free Cu-based PSCs. [ABSTRACT FROM AUTHOR]

Recently, mixed‐halide inorganic CsPbI3−xBrx perovskite solar cells (PSCs) have had a rapid advancement, which offers balanced efficiency, stability, tunable bandgap, and potential for indoor photovoltaic applications. Despite these advantages, significant challenges remain in the phase segregation phenomena, trap state density, and absorption range limitations. This review presents an analysis of the crystal and electronic structure and optical properties of CsPbI3−xBrx, as well as an in‐depth look at high‐quality CsPbI3−xBrx film preparation, phase segregation inhibition potential solutions, and interface engineering, highlighting the critical role of interface modification in the performance of CsPbI3−xBrx PSCs. Furthermore, how CsPbI3−xBrx PSCs can be strong candidates for indoor photovoltaics because of their adjustable bandgap that enables them to better match the absorption range and notable strength stability is discussed. Finally, the review provides perspectives to address the development bottlenecks and inspires future research prospects concerning CsPbI3−xBrx PSCs. [ABSTRACT FROM AUTHOR]

A typical perovskite solar cell (PSC) is composed of a perovskite layer, electron/hole transport layer(s), cathode, and anode, producing several interfaces between these functional layers. These interfaces undoubtedly have great influence on the device performance. Introducing the dipolar interlayer is one of the most significant interface engineering strategies in PSCs, which helps to improve the charge extraction and collection and has made critical contribution to the fast development of PSC technology. Herein, the progress in the use of dipolar interlayers to promote the performance of PSCs is summarized. The dipolar interlayers in PSCs based on the device structure are categorized and the effect of each type of dipolar interlayer on the interface energy‐level structure, interface charge transport and recombination, the interface defect passivation, perovskite morphology, and the device performance is discussed. A perspective on how to develop more effective dipolar interlayer materials and further enhancing the device performance from the viewpoint of the interface and dipolar interlayers is given. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskites are a promising solution for the fabrication of thermally stable perovskite solar cells (PSCs) with remarkable performances. However, a high annealing temperature is required for the stabilization of the photoactive phase of CsPbI3, which represents a limiting factor for their potential scaling‐up and manufacturing at industrial scale. This work demonstrates a new process for the stabilization of CsPbI3−xBrx perovskite at lower annealing temperature of 180°, based on a rational halogen substitution enabled by the introduction of dimethylammonium (DMA) additives. Bromide inclusion favors indeed the conversion from the intermediate phases to CsPbI3−xBrx. Standard mesoscopic solar cells prepared with this approach achieve a power conversion efficiency (PCE) of 14.86%, with reduced voltage losses and increased fill factor compared to the reference device. Moreover, this work proves that a rational substitution of the halide in the DMA salt is also beneficial for the devices annealed at higher temperature, achieving an encouraging PCE of 16.23%. By reducing the processing temperature, this new method widens the range of applications of all‐inorganic PSCs toward temperature‐sensitive materials and industrial applications. [ABSTRACT FROM AUTHOR]

Efficient and stable wide bandgap (WBG) perovskite solar cells (PSCs) are imperative for fabricating superior tandem devices. However, small crystal grains and light‐induced phase segregation of WBG perovskite result in large open‐circuit voltage (VOC) deficits, critically impeding the development of the related devices. Herein, the effective functional groups of Lewis‐base trans‐Ferulic acid (t‐FA) are employed to release the residual microstrain in the perovskite lattice. Larger perovskite crystals are formed by strengthening the interaction between the perovskite solute and solution. The lattice structure is stabilized to suppress light‐induced halide segregation. Finally, the power conversion efficiency (PCE) of the optimized device with a bandgap of ≈1.77 eV is increased from 17.33% to 19.31% with the enhancement of VOC. Moreover, replacing a mixture of MeO‐2PACZ and Me‐4PACZ as the hole transporting layer (HTL), the PCE further lifts to 19.9% and VOC is 1.32 V, one of the highest performances reported for WBG PSCs, especially for devices prepared entirely by solution spin‐coating. Therefore, this study provides a practicable alternative for realizing efficient WBG PSCs, which can contribute to the growth of perovskite‐based tandem devices. [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]

Lead‐free 2D antimony‐based halide perovskites with excellent optoelectronic properties, low toxicity, and good intrinsic stability are promising for photovoltaic devices. However, the power conversion efficiency (PCE) of antimony‐based perovskite solar cells (PSCs) is still lower than 3% due to the poor crystallinity and random orientation. Herein, it is found that the Cs3Sb2ClxI9‐x films prepared by adding methylamine chloride as an additive to the precursor solution can form a mixed intermediate phase with 0D dimer phase and 2D layered phase after low pressure treatment. During the annealing process, the 0D dimer phase will completely transition to 2D layered phase due to the partial replacement of I by Cl. Compared to adding SbCl3 directly, this method considerably increases the crystallinity of Cs3Sb2IxCl9‐x films. The obtained films have a preferential orientation along the (201) direction, which is beneficial for charge carrier transportation. Consequently, the champion device shows a PCE of 3.2%, which is one of the highest efficiencies achieved for inorganic Sb‐based PSCs with the n‐i‐p architecture to date. [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]

Hole transport materials (HTMs) are an integral part of highly efficient perovskite solar cells (PSCs). Although the traditional HTM Spiro-OMeTAD achieves excellent performance, its high cost limits its future large-scale application during commercialization of PSCs. Therefore, it is essential to develop low-cost and efficient alternative HTMs. Herein, we successfully synthesize two novel HTMs DTP-1 and DTP-2 by employing methoxy-substituted terthienyl (DTP) as the core unit and adjusting the electron donors. Research indicates that the introduction of methoxy groups on the core unit enhances its electron donating ability; thus, the capping groups with slightly lower electron donating ability should be adopted to get well-matched energy levels. After optimization, the best-performing power conversion efficiency (PCE) of DTP-1 based PSCs is 21.1%, which is much higher than those of PSCs based on DTP-2 (15.6%) and THP-1 (20.5%). Furthermore, under the conditions of RH 30–45% and room temperature, the DTP-1-based devices maintain 80.5% of the initial PCE after aging for 840 h, which is better than those of DTP-2 (22.0%) and THP-1 (71.5%). [ABSTRACT FROM AUTHOR]

Opto‐electronic models that seek to predict the performance of perovskite and tandem solar cells (PSCs/TSCs) often keep the optical and recombination parameters (ORPs) constant in subsequent studies. During fabrication of PSCs, however, these parameters can vary significantly. To account for the inherent fabrication variability, a comprehensive opto‐electronic‐electric model to predict the current–voltage characteristics of four‐terminal (4T) TSCs is developed. This model is calibrated with forty‐eight in‐house fabricated transparent PSCs with perovskite layer thickness of 420, 550, and 700 nm and corresponding median efficiencies of 20.6%, 21.1%, and 21.0%, respectively; a CIS bottom cell with stand‐alone efficiency of 17.5%; and combined 4T TSCs with a median efficiency of 29.0%. After fitting and validation, the functional forms of the ORPs are captured to estimate how they change with perovskite layer thickness. Finally, the errors with models assuming constant ORPs are demonstrated and how to improve the TSCs efficiency to more than 30% is discussed. [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]

The proliferation of fossil fuels for power generation leads to their depletion besides damaging the environment to a larger extent. In order to strive for a better environment, the inclusion of renewable energy-based generation is the best substitute. Solar, wind, hydro, and biomass are the available renewable energy sources in nature. Among the list, solar-based PV power generation is the most promising one and yields the maximum power output. In spite of all postulates from PV, the dependency on the sun makes this power generation a bit complicated. The output power generated from the PV panel varies in accordance with the solar insolation, temperature, degree of inclination, and partial shading condition. For extracting the maximum power from the PV array, various configuration techniques are implemented such as series, parallel, series-parallel, TCT, and HC. But these configuration techniques are less effective during partial shading conditions (PSCs). In order to reduce the PSC effect, static reconfiguration of modules within the PV array is implemented. This paper reviews all novel reconfiguration-based techniques which are available in the literature till date. We have systematically classified various reconfiguration methodologies. This study provides the advancement in this area since some parameter comparison is made at the end of every classification, which might be a prominent base rule for picking the most gainful sort of reconfiguration method for further research. This review would be helpful for researchers in this field to select the most feasible reconfiguration method for their application, as this study reviews a considerable number of PV reconfiguration methods on one platform. [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]

Pristine fullerene C60 is an excellent electron transport material for state‐of‐the‐art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high‐quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl‐shaped additive, corannulene, to assist in C60‐assembly into a smooth and compact film through the favorable bowl‐ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60, it also plays a critical role in forming C60‐corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution‐processed‐C60 (SP‐C60) ETL. Moreover, the stability of the CC device is far superior to that of the C60‐only device because corannulene can retard and curb the spontaneous aggregation of C60. This work establishes the bowl‐assisted ball assembly strategy for developing low‐cost and efficient SP‐C60 ETLs with high promise for fully‐SP PSCs. [ABSTRACT FROM AUTHOR]

Developing all‐perovskite tandem solar cells has been proved to be an effective approach to boost the efficiency beyond the Shockley–Queisser limit. However, the Sn‐based narrow‐bandgap (NBG) perovskite solar cells (PSCs) suffer from the relatively low photostability, which limits their further application in all‐perovskite tandem solar cells. In this work, the instability of NBG PSCs is found to come from the commonly used acidic hole transporting material PEDOT:PSS, which reacts with the indispensable basic additive SnF2 in the perovskite layer. By acidity control of PEDOT:PSS via aqueous ammonia, the NBG PSCs yield an efficiency of 22.0% with much improved photostability, which can maintain 91.3% of the initial value after 800 h illumination under AM 1.5G. As an application, the corresponding all‐perovskite tandem cells exhibit a stabilized efficiency of 25.3% with 92% remaining after 560 h illumination. This work reveals an origin of instability of NBG PSCs and provides an effective approach to enhance the device stability, which can promote the development of all‐perovskite tandem solar cells. [ABSTRACT FROM AUTHOR]

In the recently researched Sn-contained perovskite solar cells (PSCs), limited work is focused on corrosion of a metal electrode, which is recognized as the obstacle of efficient and stable devices. Here, it is found that a pure Sn based PSC shows the most serious and quick corrosion of an Ag electrode, compared with Pb and Sn–Pb PSCs. I2, SnOX, and AgI are the main products of the aged Ag electrode in Sn based PSCs, which greatly differed from Pb and Sn–Pb PSCs. Oxidation of FASnI3 under O2/H2O produces aggressive I2, together with gaseous FA and diffusive I−, degrading the PVK film and Ag electrode greatly. This work highlights the corrosion velocity and mechanism of Ag electrodes in Sn-contained PSCs, which may help to find out possible solutions to circumvent the instable issue. [ABSTRACT FROM AUTHOR]

Background: Chimera formation and germline competence are critical features of mouse pluripotent stem cells (PSCs). However, the factors that contribute to germline competence in the chimeras remain to be understood. Methods: To determine the role of Dppa3 in PSCs, we first constructed Dppa3 knockout (Dppa3 KO) and Dppa3 overexpression (Dppa3 OE) PSCs, respectively. Using Dppa3 KO and Dppa3 OE PSCs, we then investigated the role of Dppa3 in PSCs by evaluating the chimera generation, DNA methylation, and pluripotent state conversion. Results: We show that Dppa3 plays an important role in chimera formation and germline competence of mouse PSCs. PSC lines with high expression of Dppa3 show high germline competence. In contrast, Dppa3 deficiency reduces chimera formation and abrogates the germline transmission capacity of PSCs. Molecularly, Dppa3 facilitates establishing global DNA hypomethylation in PSCs. High levels of Dppa3 in PSCs reduce the expression of Dnmt3a/b and impede Uhrf1-Dnmt1 complex binding to DNA replication forks, maintaining DNA hypomethylation. Additionally, Dppa3 facilitates two-cell-stage (2C) genes expression and promotes conversion to a 2C-like state. Conclusion: These data show that Dppa3 is involved in maintaining DNA hypomethylation homeostasis and is required for high chimera formation and germline competence of PSCs. [ABSTRACT FROM AUTHOR]

Solar photovoltaic (SPV) systems are becoming key emerging technologies for both stand-alone and grid-connected power system applications. However, uncertainty in environmental conditions such as temperature and irradiation dominates the performance of the SPV system. Due to uncertainty in environmental conditions, there should be drastic reduction in output power, efficiency and higher mismatch power loss in the SPV system. This adverse phenomenon can be overawed by the inclusion of bypass diode. But the inclusion will result in multiple peaks that are developed in the P–V curve. This will necessitate a robust MPPT controller to track the global maximum power (GMP) under PSCs. Various conventional (P&O, InC etc.) and optimization algorithms are described in the literature, but they are unsuccessful to identify GMP among multiple peaks. This paper proposes a novel hybrid slime mould assisted with perturb and observe (P&O) MPPT approach (HSMO) with hybrid bridge link-honey comb (BL-HC) configured PV system to enhance the better maximum power under PSCs. The proposed work is carried out in MATLAB/Simulink environment. Also, the performance of proposed HSMO technique is compared with the latest adaptive coefficient PSO (ACPSO), Flower Pollination algorithm (FPA), and slime mould optimization (SMO) MPPT techniques in terms of tracked GMP, tracking efficiency, and convergence time/tracking speed. The results of the proposed HSMO technique also demonstrate its supremacy in terms of tracked GMP, convergence time, and efficiency. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are an attractive emerging photovoltaic technology due to their high‐performance while being made by low‐cost fabrication processes. The most efficient PSCs are small area and made by nonscalable coating method in an inert atmosphere, but these sizes and fabrication conditions are commercially irrelevant. Herein, fabrication of PSCs is reported using only scalable methods, that is, slot‐die coating and blade coating methods, all in ambient air. The tolerance to relaxed fabrication conditions is enabled by the use of hydrated nonhalogenated lead source. Resurfacing strategy is then introduced to suppress charge carrier nonradiative recombination and obtained an efficiency of 19.91% for rigid and 17.4% for flexible PSCs by all‐scalable fabrication. To the best of our knowledge, these are the highest efficiencies for n–i–p structured MAPbI3‐based PSCs in ambient air using all‐scalable method to date. The devices showed excellent tolerance to oxygen and moisture (ISOS‐D‐1) as well as stable maximum power point operation following burn in a dry air glove box (relative humidity ≈ 20%) without encapsulation. [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]

Defects and band shifts at the heterogeneous interface between the perovskite layer and the charge transport layer are two important problems that hinder the efficiency of photoelectric conversion and the stability of devices. Considering these issues, an interface engineering to reinforce the operation stability of FACsPbI3 perovskite solar cells (PSCs) by the introduction of a multifunctional ligand 2‐carboxyphenyl ethyl phosphate (CEPPA) modification layer between the electron transport layer and the perovskite layer is presented. It demonstrates that CEPPA adsorbs on the substrate surface to passivate the oxygen vacancy defects and effectively reduce the defect states on SnO2 films. On the other hand, the optimized arrangement of energy levels leads to better electron extraction and transport. Eventually, the power conversion efficiency (PCE) of the FACsPbI3 device increases from 16.33% to 17.78%. Moreover, compared with unmodified SnO2, the unpackaged devices with CEPPA‐modified SnO2 show better phase stability and moisture stability. Unpackaged devices retain more than 80% of their initial PCE after 500 h of aging. Herein, a further perspective for the analysis and development of buried interfaces and an effective approach for better improving the function and stability of PSCs are presented. [ABSTRACT FROM AUTHOR]

Improving the performance, reproducibility, and stability of Sn‐based perovskite solar cells (PSCs) with n–i–p structures is an important challenge. Spiro‐OMeTAD [2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenyl‐amine)9,9′‐spirobifluorene], a hole transporting material (HTM) with n–i–p structure, requires the oxygen exposure after addition of Li‐TFSI [Lithium bis(trifluoromethanesulfonyl)imide] as a dopant to increase the hole concentration. In Sn‐based PSC, Sn2+ is easily oxidized to Sn4+ under such a condition, resulting in a sharp decrease in efficiency. Herein, a formamidinium tin triiodide (FASnI3)‐based PSCs fabricated using DPI‐TPFB [4‐Isopropyl‐4′‐methyldiphenyliodonium tetrakis(pentafluorophenyl)borate] instead of Li‐TFSI are reported as a dopant in Spiro‐OMeTAD. The DPI‐TPFB enables the fabrication of PSCs with an efficiency of up to 10.9%, the highest among FASnI3‐based PSCs with n–i–p structures. Moreover, ≈80% of the initial efficiency is maintained even after 1,597 h under maximum power point tracking conditions. In particular, the encapsulated device does not show any decrease in efficiency even after holding for 50 h in the 85 °C/85% RH condition. The high efficiency and excellent stability of PSCs prepared by doping with DPI‐TPFB are attributed to not only increasing electrical conductivity by acting as a Lewis acid, but also stabilizing Sn2+ through coordination with Sn2+ on the surface of FASnI3. [ABSTRACT FROM AUTHOR]

A series of organic electron‐rich π‐bridged symmetric hydrazones, composed of two donor moieties connected through a thiophene‐ or a pyrrole‐based π‐spacer, has been synthesized as a suitable alternative to 2,2',7,7'‐tetrakis[N,N‐di(4‐methoxyphenyl)amino]‐9,9'‐spirobifluorene (Spiro‐OMeTAD), considered the benchmark hole transporting material (HTM) in perovskite solar cells (PSCs). The cheap synthetic protocol is suitable for potential large‐scale production. All the compounds were characterized, showing good energy levels alignments with the perovskite and very close energy levels to the Spiro‐OMeTAD. Furthermore, computational analysis confirmed the electrochemical trend observed. The costs of synthesis were estimated, as well as the produced waste to synthesise the final HTMs, underlining the low impact of these compounds on the environment with the respect to Spiro‐OMeTAD. Overall, the relevant electrochemical properties and the low cost of the synthetic approaches allow these compounds to be a greener and easy‐to‐synthesize alternative to the Spiro‐OMeTAD for industrial development of PSCs. [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]

With an ongoing pandemic claiming hundreds of lives a day, it is unclear how COVID-19 has affected court operations, particularly problem-solving courts (PSCs) which have goals rooted in rehabilitation for participants in their programs. Even with practical recommendations from national organizations directing courts on how to manage COVID-19, whether and how PSCs met the needs of PSC participants during this time is underexplored. This study, drawn from a larger national study using a survey of PSC coordinators, examines the COVID-19 responses of PSCs to remain safely operational for participants. A sub-sample of survey respondents (n = 82 PSC coordinators) detailed how the COVID-19 pandemic led to changes to their court and treatment operations amidst the constraints of the pandemic. The courts' shifts in policy and practice have important impacts for court participants' treatment retention and success in the PSC program, and these shifts need more in-depth research in the future. [ABSTRACT FROM AUTHOR]

This study employed a simulation-based approach for probing the performance-limiting parameters. Comparative observation of performance parameters with corresponding Shockley–Queisser limit values highlight a significant deficit in fill factor and open-circuit voltage (VOC) of perovskite solar cells (PSCs). This work identifies parameters such as carrier concentration, sheet resistance, and internal recombination responsible for these FF deficits in contemporary PSC. Simulation of illumination-dependent FF for these design parameters gives insight into the optimal range of parameters, which ought to be crucial to stabilize and enhance the device's performance. PSCs are sensitive toward shunt resistance and experimental PSC devices must have RSh above 5 K Ω cm2 for optimal FF and VOC values. We observed that FF is optimal in mid-carrier concentration around the range of ~ 1016 cm−3. This optimal FF could be due to the interplay between resistivity, Shockley–Read–Hall recombination and Auger recombination at these carrier densities. We summarize pathways such as shunt resistance values, carrier concentration, and back contact optimization work function to maximize FF in PSC. The optimized device with the derived design parameters has achieved a Voc, Jsc, FF and PCE of 1.3248 V, 22.93 mA/cm2, 79.39% and 23.22% respectively. [ABSTRACT FROM AUTHOR]

In recent years, researchers have developed spray deposition technology to fabricate tin oxide electron transport layer (ETL) with the aim of manufacturing high‐efficiency, large‐area perovskite solar cell (PSC). However, the power conversion efficiency (PCE) of PSC based on sprayed SnO2 ETL remains inferior to that of the spin‐coated SnO2 ETL. Herein, the combined use of spray deposition and genetically engineered M13 bacteriophages for the deposition of M13‐SnO2 biohybrid ETL over large‐area (62.5 cm2) substrates is demonstrated. The spray‐deposited M13‐SnO2 ETLs exhibit mesoporous morphologies with >85% transmittance in UV–vis region. Through the use of M13‐SnO2 ETL, the sequential‐deposited PSCs achieve a maximum PCE of ≈22.1%. The improved performance of the PSC is attributable to the mesoporous morphology of M13‐SnO2 ETL that facilitates the growth of larger perovskite grains. The PSCs based on M13‐SnO2 ETLs also display highly consistent photovoltaic performance which manifests the excellent scalability of the spraying process. Furthermore, M13‐SnO2‐based PSCs exhibit higher ambient stability compared to the SnO2‐based PSCs, showing that the use of M13 bacteriophage is incredibly beneficial to both the efficiency and stability of PSCs. [ABSTRACT FROM AUTHOR]

Formamidinium lead triiodide (FAPbI3) with an optimal bandgap of 1.48 eV and superior thermal stability is regarded as one of the most promising perovskite‐based materials for the application in efficient single‐junction solar cells. However, the metastable properties of FAPbI3 due to phase transition from photoactive α phase into an undesired nonperovskite δ phase in ambient conditions become the major factors limiting its further development. Challenges remain in stabilizing α phase structure and preparing phase‐pure α‐FAPbI3 films for high‐efficiency and stable perovskite solar cells (PSCs) devices. Herein, the recent research progress on the strategies is reviewed to fabricate phase‐pure α‐FAPbI3 perovskite and the advances in their photovoltaic application. The physical parameters affecting the phase instability of intrinsic FAPbI3 are first discussed, followed by various methodologies for regulating phase transition behavior, such as additive engineering, solvent optimization, dimensionality engineering, and fabrication techniques. Finally, the fundamental challenges of preparing efficient α‐FAPbI3 PSCs are discussed, and the perspectives on the further development of high‐quality phase‐pure α‐FAPbI3 for reliable PSCs are proposed. [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]

Polymer matrix is felicitously applied into the active layer and transporting layer of perovskite solar cells (PSCs) to enable a stretchable function. However, the chaotic deposition of polymer chains is the main cause for the inferior photoelectric performance. When the stretchable PSCs are in a working state, the stress cannot be removed effectively due to the random polymer chain deposition. The stress accumulation will cause irreversible damage to the stretchable PSCs. Herein, the structural bionics and patterned‐meniscus coating technology are combined to print the polymer chain‐oriented deposition in the stretchable PSCs. Based on this approach, the conducting polymer electrode is printed with both significant mechanical stability and conductivity. More importantly, the oriented polyurethane with self‐healing property can enhance the crystal quality of perovskite films and repair perovskite cracks caused by stress destruction. Thus, the corresponding stretchable PSCs achieve a stabilized power conversion efficiency (PCE) of 20.04% (1.0 cm2) and 16.47% (9 cm2) with minor efficiency discrepancy. Notably, the stretchable PSCs can maintain 86% of the primitive PCE after 1000 cycles of bending with a stretch ratio of 30%. This directional growth of polymer chain strategy provides guidance for printing prominent‐performance stretchable PSCs. [ABSTRACT FROM AUTHOR]

We report a solution-processing method to prepare an inorganic LaNiO3 (LNO) hole-transport layer (HTL) under low temperature (<150 °C) for the first time. The inverted PSCs prepared with LNO exhibit high UV-stability and promising efficiency (17.15%). Our preliminary results show great potential for LNO HTL in the fabrication of efficient and photostable inverted perovskite solar cells (PSCs). [ABSTRACT FROM AUTHOR]

Defects in perovskite are key factors in limiting the photovoltaic performance and stability of perovskite solar cells (PSCs). Generally, choline halide (ChX) can effectively passivate defects by binding with charged point defects of perovskite. However, we verified that ChI can react with CsPbI3 to form a novel crystal phase of one‐dimensional (1D) ChPbI3, which constructs 1D/3D heterostructure with 3D CsPbI3, passivating the defects of CsPbI3 more effectively and then resulting in significantly improved photoluminescence lifetime from 20.2 ns to 49.4 ns. Moreover, the outstanding chemical inertness of 1D ChPbI3 and the repair of undesired δ‐CsPbI3 deficiency during its formation process can significantly enhance the stability of CsPbI3 film. Benefiting from 1D/3D heterostructure, CsPbI3 carbon‐based PSCs (C‐PSCs) delivered a champion efficiency of 18.05 % and a new certified record of 17.8 % in hole transport material (HTM)‐free inorganic C‐PSCs. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) and organic solar cells (OSCs) face device efficiency losses and instability challenges with existing hole transport materials (HTMs). The development of new universal HTMs is in great demand to promote their practical applications. Herein, a versatile self‐assembled molecule (SAM) based HTM is designed for record‐high efficiency wide‐bandgap (WBG, Eg >1.75 eV) PSCs, all‐perovskite tandem solar cells (TSCs) and OSCs. The SAM exhibits high transmission and a lower‐lying energy level, enabling enhanced interfacial charge transfer and suppressed non‐radiative recombination losses. SAM based WBG PSCs deliver a maximum power conversion efficiency (PCE) of 18.63% with over 90% efficiency retention after 250 h continuous work. By stacking the optimal WBG PSC and a narrow‐bandgap PSC bottom cell, the 4‐terminal all‐perovskite TSC achieves a remarkable 26.24% PCE. More importantly, this SAM based HTM exhibits impressive generality in bulk heterojunction OSCs rivalling PEDOT:PSS, with an impressive PCE of 18.84% obtained for PM6:BTP‐eC9 based devices. When scaling up the PM6:BTP‐eC9 device to 0.5 cm2 in area (0.71 cm × 0.71 cm), the SAM based OSCs afford a highest PCE of 16.33%. This work provides a perspective for the design of universal SAM based charge transport materials targeting PSCs and OSCs for facile large‐area fabrication. [ABSTRACT FROM AUTHOR]