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Nonradiative recombination losses occurring at the interface pose a significant obstacle to achieve high‐efficiency perovskite solar cells (PSCs), particularly in inverted PSCs. Passivating surface defects using molecules with different functional groups represents one of the key strategies for enhancing PSCs efficiency. However, a lack of insight into the passivation orientation of molecules on the surface is a challenge for rational molecular design. In this study, aminothiol hydrochlorides with different alkyl chains but identical electron‐donating (−SH) and electron‐withdrawing (−NH3+) groups were employed to investigate the interplay between molecular structure, orientation, and interaction on perovskite surface. The 2‐Aminoethane‐1‐thiol hydrochloride with shorter alkyl chains exhibited a preference of parallel orientations, which facilitating stronger interactions with the surface defects through strong coordination and hydrogen bonding. The resultant perovskite films following defect passivation demonstrate reduced ion migration, inhibition of nonradiative recombination, and more n‐type characteristics for efficient electron transfer. Consequently, an impressive power conversion efficiency of 25 % was achieved, maintaining 95 % of its initial efficiency after 500 hours of continuous maximum power point tracking. [ABSTRACT FROM AUTHOR]

The hole‐transporting material (HTM), poly (3,4‐ethylene dioxythiophene) poly(styrene sulfonate) (PEDOT : PSS), is the most widely used material in the realization of high‐efficiency organic solar cells (OSCs). However, the stability of PEDOT : PSS‐based OSCs is quite poor, arising from its strong acidity and hygroscopicity. In addition, PEDOT : PSS has an absorption in the infrared region and high highest occupied molecular orbital (HOMO) energy level, thus limiting the enhancement of short‐circuit current density (Jsc) and open‐circuit voltage (Voc), respectively. Herein, two asymmetric self‐assembled molecules (SAMs), namely BrCz and BrBACz, were designed and synthesized as HTM in binary OSCs based on the well‐known system of PM6 : Y6, PM6 : eC9, PM6 : L8‐BO, and D18 : eC9. Compared with BrCz, BrBACz shows larger dipole moment, deeper work function and lower surface energy. Moreover, BrBACz not only enhances photon harvesting in the active layer, but also minimizes voltage losses as well as improves interface charge extraction/ transport. Consequently, the PM6 : eC9‐based binary OSC using BrBACz as HTM exhibits a champion efficiency of 19.70 % with a remarkable Jsc of 29.20 mA cm−2 and a Voc of 0.856 V, which is a record efficiency for binary OSCs so far. In addition, the unencapsulated device maintains 95.0 % of its original efficiency after 1,000 hours of storage at air ambient, indicating excellent long‐term stability. [ABSTRACT FROM AUTHOR]

Land use and rainfall are two important factors affecting soil erosion processes. The red soil region of southern China is a representative region with high rainfall amounts and rapidly changing land use patterns where the water erosion process is sensitive to changes in land use and rainfall. To comprehensively understand the water erosion response to land use and rainfall in this region, a 6-year in situ experiment based on eight plots (bare land and seven typical land uses) was conducted from 2015 to 2020. The 320 rainfall events were divided into 4 types, and there were 3 main rainfall types. The runoff of different rainfall types was primarily determined by the rainfall amount, while the soil erosion of different rainfall types was primarily determined by the rainfall intensity. High-intensity rainfall contributed the most to both total runoff and soil erosion. Compared with bare land, the seven typical land uses reduced runoff and soil erosion by more than 75%. Grassland, cropland, and forest with low vegetation coverage experienced high runoff and soil erosion, while shrubland most effectively reduced runoff and soil erosion. The combination of land use and rainfall type significantly affected the annual average runoff depth, soil erosion modulus, and soil loss coefficient. Rainfall types can change the relationship between runoff and soil erosion for different land uses. The runoff and soil erosion of bare land were highly correlated with rainfall characteristics, while vegetation weakened this relationship under short- or moderate-duration rainfall. To effectively reduce water erosion, high-intensity rainfall should receive special attention, and all land uses should ensure that vegetation is well developed, especially understory vegetation. [ABSTRACT FROM AUTHOR]

The main obstacles to promoting the commercialization of perovskite solar cells (PSCs) include their record power conversion efficiency (PCE), which still remains below the Shockley–Queisser limit, and poor long‐term stability, attributable to crystallographic defects in perovskite films and open‐circuit voltage (Voc) loss in devices. In this study, potassium (4‐tert‐butoxycarbonylpiperazin‐1‐yl) methyl trifluoroborate (PTFBK) was employed as a multifunctional additive to target and modulate bulk perovskite defects and carrier dynamics of PSCs. Apart from simultaneously passivating anionic and cationic defects, PTFBK could also optimize the energy‐level alignment of devices and weaken the interaction between carriers and longitudinal optical phonons, resulting in a carrier lifetime of greater than 3 μs. Furthermore, it inhibited non‐radiative recombination and improved the crystallization capacity in the target perovskite film. Hence, the target rigid and flexible p‐i‐n PSCs yielded champion PCEs of 24.99 % and 23.48 %, respectively. More importantly, due to hydrogen bonding between formamidinium and fluorine, the target devices exhibited remarkable thermal, humidity, and operational tracking at maximum power point stabilities. The reduced Young's modulus and residual stress in the perovskite layer also provided excellent bending stability for flexible target devices. [ABSTRACT FROM AUTHOR]

Molecular stacking and orientation are of great importance in regulating optoelectronic properties. Typically, the face‐on orientation of hole transporting materials (HTMs) is considered to be a prerequisite for the realization of high efficiency perovskite solar cells (PSCs). Herein, a small molecule HTM, BDT‐p‐IDN, is developed with edge‐on orientation by replacing the terminal group from diphenylamine to indoline unit. Remarkably, the PSCs device based on dopant‐free BDT‐p‐IDN exhibits an efficiency of 23.28%, which is comparable to that of its face‐on control BDT‐DPA‐F. Compared to BDT‐DPA‐F, BDT‐p‐IDN has stronger interaction with the perovskite (PVK) film and therefore stronger hole extraction and defect passivation capabilities, resulting in an increased short circuit current density and improved efficiency. The results indicate that edge‐on orientation could be a powerful way for HTMs to realize efficient PSCs. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) have attracted a great deal of attention in the field of clean solar energy due to their advantages of transparency, flexibility, low cost and light weight. Introducing them to the market enables seamless integration into buildings and windows, while also supporting wearable, portable electronics and internet-of-things (IoT) devices. With the development of photovoltaic materials and the optimization of fabrication technology, the power conversion efficiencies (PCEs) of OSCs have rapidly improved and now exceed 20%. However, there is a significant lack of focus on material stability and device lifetime, causing a severe hindrance to commercial applications. In this review, we carefully review important strategies employed to improve the stability of OSCs over the past three years from the perspectives of material design and device engineering. Furthermore, we analyze and discuss the current important progress in terms of air, light, thermal and mechanical stability. Finally, we propose the future research directions to overcome the challenges in achieving highly stable OSCs. We expect that this review will contribute to solving the stability problem of OSCs, eventually paving the way for commercial applications in the near future. [ABSTRACT FROM AUTHOR]

In recent years, the surface modification of perovskite by wide band‐gap insulating materials has been one of the main strategies to achieve efficient and stable perovskite solar cells (PSCs). Unfortunately, a significant hurdle in this approach is the dilemma surrounding the quality of passivation and the transport of charges. Here, this trade‐off is overcome by introducing self‐assembled diphenylphosphinic acid (DPPA) porous layer. Applying highly concentrated DPPA solution on the perovskite surface not only provides excellent passivation of entire surface, but also the excess DPPA will form a self‐assembled porous insulating layer (PIL), which forms random submicron‐sized openings at the interface of the insulating layer for accelerated charge transport. In addition, the energy level of the perovskite surface can be modulated by this insulating material to facilitate carrier transport. As a result, an impressive power conversion efficiency (PCE) over 24% has been achieved in methylammonium‐free p‐i‐n devices with an ultrahigh fill factor (FF) of 84.7%. The unencapsulated devices exhibit excellent thermal and operational stability. This work paves a way for establishment of an effective passivation and facilitated transport simultaneously. [ABSTRACT FROM AUTHOR]

The wearable application of flexible organic solar cells (f‐OSCs) necessitates high power conversion efficiency (PCE) and mechanical robustness. However, photoactive films based on efficient non‐fullerene small molecule acceptors (NF‐SMAs) are typically brittle, leading to poor mechanical stability in devices. In this study, we achieved a remarkable PCE of 18.06 % in f‐OSCs while maintaining ultrahigh mechanical robustness (with a crack‐onset strain (COS) of higher than 11 %) by incorporating a linker dimerized acceptor (DOY‐TVT). Compared to binary blends, ternary systems exhibit reduced non‐radiative recombination, suppressed crystallization and diffusion of NF‐SMAs, and improved load distribution across the chain networks, enabling the dissipation of the load energy. Thus, the ternary f‐OSCs developed in this study achieved, high PCE and stability, surpassing binary OSCs. Moreover, the developed f‐OSCs retained 97 % of the initial PCE even after 3000 bending cycles, indicating excellent mechanical stability (9.1 % higher than binary systems). Furthermore, the rigid device with inverted structure based on the optimal active layer exhibited a substantial increase in efficiency retention, with 89.6 % after 865 h at 85 °C and 93 % after more than 1300 h of shelf storage at 25 °C. These findings highlight the potential of the linker oligomer acceptor for realizing high‐performing f‐OSCs with ultrahigh mechanical robustness. [ABSTRACT FROM AUTHOR]

Substantial efforts of A–DA′D–A type non‐fullerene acceptors (NFAs) molecular design have impelled power conversion efficiency (PCE) of single junction organic solar cells (OSCs) to exceed 19%. Asymmetric geometry strategy, selenium‐substitution, and end‐group engineering are proven to be effective modification methods. Here, two novel selenium substitution asymmetric NFAs, AsymSSe‐2F, and AsymSSe‐2Cl, are synthesized to investigate the synergistic modification effects on device performance compared with symmetric Y6. When blending AsymSSe‐2F with the wide‐bandgap and high crystallinity polymer D18, a remarkable PCE of 18.31% is yielded, and an excellent fill factor of 79.46% is achieved, which is attributed to the broadened absorption, enhanced π–π stacking, balanced carrier mobilities, and fine phase‐separation morphology. Notably, among the reported selenium‐substituted asymmetric NFAs based OSCs, especially combined with the seldom‐reported D18, this PCE is top‐ranked in binary bulk heterojunction organic solar cells. This work indicates that the combined modification of asymmetric geometry and selenium substitution in NFAs is a promising strategy for fabricating high performance OSCs. [ABSTRACT FROM AUTHOR]

In view of the meshing impact of the gear pairs of the experimental prototype based on the new-type of the planetary reducer with few teeth difference,which is proposed by Xiao Nanping and received the patent for this invention,the three-dimensional model of this reducer established by Solid Works is introduced into the ADAMS to build the model of the virtual prototyping of the reducer.The correctness of this virtual prototype is proved by the simulation of the angular velocity of the input and output shaft and the changing law of the meshing force of the gear pairs with the help of the software ADAMS.And the inertia force caused by the eccentricity of the planet gear has little influence on the meshing force of the gear pairs by comparing the simulation results with the theoretical calculation.And this result can provide the data support for calculating the strength of the gear pairs precisely and analyzing the contact stress of the pairs.

The structure of the new-type of the planetary reducer with few teeth difference,which is proposed by Xiao Nanping and received the patent for this invention are introduced. The finite element model of this reducer box is established by using the software ANSYS Workbench. The statics analysis is carried out,the changing curve for each actual loading conditions of the reducer box,and the changing curve of the maximum stress and the deformation are obtained,this analysis results can provide the data support for the subsequent structure improvement and weight reduction. The natural frequency and vibration type are obtained by completing the modal analysis of this box,and whether the resonance phenomenon happens can be determined by comparing the natural frequency of this reducer with the meshing frequency and the rotational frequency. It also offers a theoretic reference for the structure optimization design and following research of vibration problems for reducers.

The paper primarily employs the 3D calculation method of the helical gear-meshing line and meshing position, in addition to the traditional method of the gear-meshing stiffness calculation. This analysis and correction of load-sharing are beneficial for improving the assembly process of high-powered critical equipment. The dynamic models of rigid–flexible coupling, velocity–torque, and the meshing force of planetary gear trains in nuclear power plants are established based on the principles of gear dynamic characteristics. Based on an analysis of the vibration characteristics of a planetary gear train, a load-sharing method for the planetary gear train is proposed. This uniform load-sharing method is explored under different modification values to provide a reference for load-sharing research on high-powered key equipment. In this paper, a dynamic simulation analysis of the gearbox system is conducted, using virtual prototype software to study the load-sharing performance of the planetary gear system. Furthermore, via a vibration frequency analysis of the gear mesh force, the causes of planetary gear train vibration are discussed, particularly their impact on planetary load. This provides a basis for the assembly process of a nuclear power circulation pump gearbox, ensuring that the gearbox for the circulation pump has a longer life that meets the 40-year service life requirement, and provides a foundation for the study of planetary load characteristics. [ABSTRACT FROM AUTHOR]

Despite the great progress of flexible perovskite solar cells (f‐PSCs), it still faces several challenges during the homogeneous fabrication of high‐quality perovskite thin films, and overcoming the insufficient exciton dissociation. To the ends, we rationally design the ferroelectric two‐dimensional (2D) perovskite based on pyridine heterocyclic ring as the organic interlayer. We uncover that incorporation of the ferroelectric 2D material into 3D perovskite induces an increased built‐in electric field (BEF), which enhances the exciton dissociation efficiency in the device. Moreover, the 2D seeds could assist the 3D crystallization by forming more homogeneous and highly‐oriented perovskite crystals. As a result, an impressive power conversion efficiency (PCE) over 23 % has been achieved by the f‐PSCs with outstanding ambient stability. Moreover, the piezo/ferroelectric 2D perovskite intrigues a decreased hole transport barriers at the ITO/perovskite interface under tensile stress, which opens new possibilities for developing highly‐efficient f‐PSCs. [ABSTRACT FROM AUTHOR]

As a multigroup cross‐linking agent, amino acid derivatives contain different kinds of characteristic functional groups with different characteristics. Aiming at one of the most difficult problems, ionic defects, amino acid derivatives can passivate these defects through their multifunctional groups. Ionic defects (such as organic cations and halogen anions) mostly exist on surface and/or grain boundaries of perovskite films, and amino acid derivatives promote the formation of high‐quality perovskite films by coordinating well with these defects. Herein, the effects of two kinds of amino acids (l‐arginine and l‐glutamic acid) with contrastive isoelectric points (pIs) on perovskite film formation, defect passivation mechanism, device efficiency, flexible substrate, and thermal/moisture stability are studied. Efficiency of inverted perovskite solar cells is improved from ≈20% to nearly 23% with additives on rigid substrates. High pI l‐arginine improves the open‐circuit voltage significantly, while low pI l‐glutamic acid excels in fill factor and short‐circuit current. More importantly, low pI l‐glutamic acid shows superior thermal and moisture stability, indicating inherent stronger bonding between l‐glutamic acid and perovskite. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Inverted (p‐i‐n) perovskite solar cells (PSCs) are favored by researchers owing to their superior compatibility with flexible substrates and tandem device fabrication. Additionally, the hole transport layer (HTL) serves as a template for perovskite growth, which is critical for enhancing the device performance. However, the current research on how the HTL promotes perovskite crystallization is insufficient. Here, 4PADCB, a self‐assembled monolayer (SAM) hole transport material, was optimized as a superior template for perovskite growth through comparative analysis; accordingly, compact perovskite film with vertical growth was prepared. The better matched energy level alignment between 4PADCB and perovskite suppressed nonradiative recombination at the interface and enabled rapid hole extraction. Moreover, high‐quality perovskite film growth on 4PADCB exhibited lower Young's modulus and less residual stress. By integrating 4PADCB into p‐i‐n PSCs, the optimal device achieved a power conversion efficiency of 24.80%, with an open‐circuit voltage of 1.156 V, thus achieving the best rank among devices without perovskite post‐treatment, additives, dopants, or intermediate layers. Furthermore, the unencapsulated device demonstrated exceptional thermostability and photostability under maximum power point tracking. Thus, this work provides a new understanding for the development of novel SAMs and perovskite growth, and it is expected to further improve device performance. [ABSTRACT FROM AUTHOR]

The spatial differentiation of forest canopy branches and leaves affects rainfall interception. However, the scientific expression of the spatial differentiation of forest canopy branches and leaves has not been clarified, and revealing the effect of spatial differentiation of branches and leaves of the vertical structure of the forest canopy on rainfall interception is difficult. Using the Pinus massoniana planted in Changting County, China, as the research object, this study quantified the spatial differentiation of canopy branches and leaves in a hierarchical manner by combining the unmanned aerial vehicle (UAV) three-dimensional point cloud model with the landscape metrics and further simulated the interception mechanism of Pinus massoniana forest canopy on rainfall of different intensities by constructing the principal component regression model. The results showed that the spatial differentiation of canopy branches and leaves in different strata responds differently to different rainfall intensities. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS) nanosheets are a promising lubricant additive for enhanced engine efficiency in cars. However, high-cost production methods and poor dispersion have limited their application in industry. In this study, the ball milling process is demonstrated as a low-cost and high-efficient method for fabrication of oil-dispersible MoS nanosheet, and the ball milling parameters are optimized. Moreover, the lubrication effectiveness of ball-milled MoS nanosheet was also evaluated. Results indicated that well-dispersed MoS nanosheets with a size of 250 nm can be manufactured with optimized surfactants of zinc dialkyldithiphosphates (ZDDP) and polyisobutylene succinimide (PIBS) after being ball milled for 36 h. Tribological results revealed that a friction coefficient of white oil with 0.25% MoS nanosheets reached 0.075, much lower than that of lubricant without nanosheets (0.16). The wear scar radius of 0.015% MoS nanosheets was similar with that of Hertz contact, and the wear scar radius reduction reached 20% compared with that of 1% ZDDP. In addition, EDS and XPS results indicated the formation of a MoS and FeS tribofilm on the wear surface. [ABSTRACT FROM AUTHOR]

The compatibility and effectiveness of nanoparticles with the existing additives in formulated oil are still unclear. In the present study, some lubricant additives were selected to modify nanoparticles to obtain friendly capped nano-MoS2. Various polyisobutyleneamine succinimide (PIBS) concentrations were applied to investigate the lubrication effectiveness of capped nano-MoS2. The results showed that the reduction in COF and wear volume of friendly capped nanoparticles without PIBS reached about 35% and 75% in comparison with those of the base oil respectively. However, the average coefficient of friction and wear volume loss of nano oil increased with PIBS concentration in the range of 0.05%-1%. By scanning electron microscope, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy analysis, it is identified that (i) MoS2 tribofilm was formed on the wear track for the oil with nano-MoS2 and (ii) wear scar was smooth for nano-MoS2 with low PIBS concentration and without PIBS, while it showed plowing wear when containing high PIBS concentration. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Smog has become a public environmental crisis in most areas of China, and in response, research efforts have mainly focused on the chemical properties of smog and its impact on human health. However, in-depth research on the public’s perception of smog has not yet been conducted. A survey of residents living around eight state-controlled atmospheric environmental monitoring sites in Ningbo City was conducted using stratified sampling. The data was statistically analyzed to investigate people’s views and behavioral tendencies in smog weather, the influence of different media reports on public outlook, and public opinions on the local atmosphere and pollution management in different areas. The results showed that people’s perception of smog differs greatly from actual conditions, indicating that the public opinion tends to deviate when faced with a public crisis. Mainstream media (TV, newspaper, etc.), accounting for 67% of all media sources, are the main source for dissemination of smog information. The main sources of pollution, in order of decreasing contribution, according to residents of Ningbo City are as follows: motor vehicle exhaust, industrial coal combustion, large-scale construction, biomass burning, and kitchen fumes. Implications: Since 2011, most areas of China have been affected by frequent smog. Most research on smog has been concentrated on its causes, alert systems, and prevention measures, whereas in-depth research on the public perception of smog has not yet been conducted. When a risky environmental event such as smog occurs, consequences may be more serious than the event itself will cause if people take irrational measures because of lacking relevant knowledge. Therefore, investigating people’s attitude and response to smog is both theoretically and practically significant. [ABSTRACT FROM PUBLISHER]

Ecotourism is an important path to sustainable tourism that has experienced rapid development in recent years. Thus, ecological principles have been considered as the guidelines for tourism and the need to protect the eco-environment has increased substantially. On this basis, the ecotourism planning, a new paradigm for tourism planning, has emerged and it has benefits in terms of both economic development and environmental conservation. The ecotourism planning is based on two important criteria: local tourism resources and ecotourism carrying capacity. In this study, we aimed to investigate the local tourism resources and calculate the ecotourism carrying capacity of Shangri-La County as an example. The results showed that Shangri-La County has abundant tourism resources and a vast diversity of tourism products. However, the natural resources in Shangri-La County are currently being exploited beyond the carrying capacity. Solutions to this problem mainly include sustainable exploitation of tourism resources; better handling of tourism demands by improving the repartitioning of tourism flow; and the development of a digital system to facilitate the management of tourism. [ABSTRACT FROM PUBLISHER]

Nonradiative recombination losses occurring at the interface pose a significant obstacle to achieve high-efficiency perovskite solar cells (PSCs), particularly in inverted PSCs. Passivating surface defects using molecules with different functional groups represents one of the key strategies for enhancing PSCs efficiency. However, a lack of insight into the passivation orientation of molecules on the surface is a challenge for rational molecular design. In this study, aminothiol hydrochlorides with different alkyl chains but identical electron-donating (-SH) and electron-withdrawing (-NH 3 + ) groups were employed to investigate the interplay between molecular structure, orientation, and interaction on perovskite surface. The 2-Aminoethane-1-thiol hydrochloride with shorter alkyl chains exhibited a preference of parallel orientations, which facilitating stronger interactions with the surface defects through strong coordination and hydrogen bonding. The resultant perovskite films following defect passivation demonstrate reduced ion migration, inhibition of nonradiative recombination, and more n-type characteristics for efficient electron transfer. Consequently, an impressive power conversion efficiency of 25 % was achieved, maintaining 95 % of its initial efficiency after 500 hours of continuous maximum power point tracking., (© 2024 Wiley-VCH GmbH.)

The hole-transporting material (HTM), poly (3,4-ethylene dioxythiophene) poly(styrene sulfonate) (PEDOT : PSS), is the most widely used material in the realization of high-efficiency organic solar cells (OSCs). However, the stability of PEDOT : PSS-based OSCs is quite poor, arising from its strong acidity and hygroscopicity. In addition, PEDOT : PSS has an absorption in the infrared region and high highest occupied molecular orbital (HOMO) energy level, thus limiting the enhancement of short-circuit current density (J sc ) and open-circuit voltage (V oc ), respectively. Herein, two asymmetric self-assembled molecules (SAMs), namely BrCz and BrBACz, were designed and synthesized as HTM in binary OSCs based on the well-known system of PM6 : Y6, PM6 : eC9, PM6 : L8-BO, and D18 : eC9. Compared with BrCz, BrBACz shows larger dipole moment, deeper work function and lower surface energy. Moreover, BrBACz not only enhances photon harvesting in the active layer, but also minimizes voltage losses as well as improves interface charge extraction/ transport. Consequently, the PM6 : eC9-based binary OSC using BrBACz as HTM exhibits a champion efficiency of 19.70 % with a remarkable J sc of 29.20 mA cm -2 and a V oc of 0.856 V, which is a record efficiency for binary OSCs so far. In addition, the unencapsulated device maintains 95.0 % of its original efficiency after 1,000 hours of storage at air ambient, indicating excellent long-term stability., (© 2024 Wiley‐VCH GmbH.)

The main obstacles to promoting the commercialization of perovskite solar cells (PSCs) include their record power conversion efficiency (PCE), which still remains below the Shockley-Queisser limit, and poor long-term stability, attributable to crystallographic defects in perovskite films and open-circuit voltage (V oc ) loss in devices. In this study, potassium (4-tert-butoxycarbonylpiperazin-1-yl) methyl trifluoroborate (PTFBK) was employed as a multifunctional additive to target and modulate bulk perovskite defects and carrier dynamics of PSCs. Apart from simultaneously passivating anionic and cationic defects, PTFBK could also optimize the energy-level alignment of devices and weaken the interaction between carriers and longitudinal optical phonons, resulting in a carrier lifetime of greater than 3 μs. Furthermore, it inhibited non-radiative recombination and improved the crystallization capacity in the target perovskite film. Hence, the target rigid and flexible p-i-n PSCs yielded champion PCEs of 24.99 % and 23.48 %, respectively. More importantly, due to hydrogen bonding between formamidinium and fluorine, the target devices exhibited remarkable thermal, humidity, and operational tracking at maximum power point stabilities. The reduced Young's modulus and residual stress in the perovskite layer also provided excellent bending stability for flexible target devices., (© 2024 Wiley‐VCH GmbH.)

While significant advancements in power conversion efficiencies (PCEs) of α-FAPbI 3 perovskite solar cells (PSCs) have been made, attaining controllable perovskite crystallization is still a considerable hurdle. This challenge stems from the initial formation of δ-FAPbI 3 , a more energetically stable phase than the desired black α-phase, during film deposition. This disrupts the heterogeneous nucleation of α-FAPbI 3 , causing the formation of mixed phases and defects. To this end, polarity engineering using molecular additives, specifically ((methyl-sulfonyl)phenyl)ethylamines (MSPEs) are introduced. The findings reveal that the interaction of PbI 2 -MSPEs-FAI intermediates is enhanced with the increased polarity of MSPEs, which in turn expedites the nucleation of α-FAPbI 3 . This leads to the development of high-quality α-FAPbI 3 films, characterized by vertical crystal orientation and reduced residual stresses. Additionally, the increased dipole moment of MSPE at perovskite grain boundaries attenuates Coulomb attractions among charged defects and screens carrier capture process, thereby diminishing non-radiative recombination. Utilizing these mechanisms, PSCs treated with highly polar 2-(4-MSPE) achieve an impressive PCE of 25.2% in small-area devices and 20.5% in large-area perovskite solar modules (PSMs) with an active area of 70 cm 2 . These results demonstrate the effectiveness of this strategy in achieving controllable crystallization of α-FAPbI 3 , paving the way for scalable-production of high-efficiency PSMs., (© 2023 Wiley‐VCH GmbH.)

The wearable application of flexible organic solar cells (f-OSCs) necessitates high power conversion efficiency (PCE) and mechanical robustness. However, photoactive films based on efficient non-fullerene small molecule acceptors (NF-SMAs) are typically brittle, leading to poor mechanical stability in devices. In this study, we achieved a remarkable PCE of 18.06 % in f-OSCs while maintaining ultrahigh mechanical robustness (with a crack-onset strain (COS) of higher than 11 %) by incorporating a linker dimerized acceptor (DOY-TVT). Compared to binary blends, ternary systems exhibit reduced non-radiative recombination, suppressed crystallization and diffusion of NF-SMAs, and improved load distribution across the chain networks, enabling the dissipation of the load energy. Thus, the ternary f-OSCs developed in this study achieved, high PCE and stability, surpassing binary OSCs. Moreover, the developed f-OSCs retained 97 % of the initial PCE even after 3000 bending cycles, indicating excellent mechanical stability (9.1 % higher than binary systems). Furthermore, the rigid device with inverted structure based on the optimal active layer exhibited a substantial increase in efficiency retention, with 89.6 % after 865 h at 85 °C and 93 % after more than 1300 h of shelf storage at 25 °C. These findings highlight the potential of the linker oligomer acceptor for realizing high-performing f-OSCs with ultrahigh mechanical robustness., (© 2023 Wiley-VCH GmbH.)

Despite the great progress of flexible perovskite solar cells (f-PSCs), it still faces several challenges during the homogeneous fabrication of high-quality perovskite thin films, and overcoming the insufficient exciton dissociation. To the ends, we rationally design the ferroelectric two-dimensional (2D) perovskite based on pyridine heterocyclic ring as the organic interlayer. We uncover that incorporation of the ferroelectric 2D material into 3D perovskite induces an increased built-in electric field (BEF), which enhances the exciton dissociation efficiency in the device. Moreover, the 2D seeds could assist the 3D crystallization by forming more homogeneous and highly-oriented perovskite crystals. As a result, an impressive power conversion efficiency (PCE) over 23 % has been achieved by the f-PSCs with outstanding ambient stability. Moreover, the piezo/ferroelectric 2D perovskite intrigues a decreased hole transport barriers at the ITO/perovskite interface under tensile stress, which opens new possibilities for developing highly-efficient f-PSCs., (© 2022 Wiley-VCH GmbH.)

Objective: To evaluate the short-term effectiveness of arthroscopic surgery combined with direct anterior approach for hip diseases., Methods: A retrospective study was performed on 23 cases with hip diseases (23 hips), who were treated with the arthroscopic surgery combined with direct anterior approach, between January 2015 and December 2016. There were 9 males and 14 females, aged from 27 to 49 years (mean, 38.6 years). There were 11 cases of posterior dislocation of the hip associated with femoral head fracture (Pipkin typeⅠ) and 7 cases of femoral neck fracture (Garden type Ⅳ). And the interval between injury and operation was 2-8 days (mean, 4.3 days). Five cases were osteonecrosis of femoral head at precollapse stage which were rated as stageⅡA according to Association Research Circulation Osseous (ARCO) classification system. The disease duration was 3-8 months (mean, 5.9 months). The preoperative Harris hip score, Oxford Hip Score (OHS), Postel score, and visual analogue scale (VAS) were 57.3±8.2, 11.2±3.6, 3.2±1.5, and 7.2±1.3, respectively., Results: All the wounds healed primarily. Lateral femoral nerve injury occurred in 3 cases. All patients were followed up 8-19 months (mean, 15.6 months). Bone union achieved in all patients after 14-19 weeks (mean, 15.8 weeks) and no secondary osteoarthritis or heterotopic ossification occurred. At last follow-up, the Harris hip score (92.5±5.3), OHS (36.5±5.9), and Postel score (14.2±2.6) were significantly higher than preoperative scores ( t =45.274, P =0.000; t =36.586, P =0.000; t =32.486, P =0.000), and VAS score (1.8±0.9) was significantly lower than preoperative score ( t =21.314, P =0.000)., Conclusion: Arthroscopic surgery combined with direct anterior approach for hip diseases can effectively relieve pain, improve hip function, and obtain the satisfactory short-term effectiveness.