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The interfacial contacts between the electron transporting layers (ETLs) and the photoactive layers are crucial to device performance and stability for OSCs with inverted architecture. Herein, atomic layer deposition (ALD) fabricated ultrathin Al2O3 layers are applied to modify the ETLs/active blends (PM6:BTP‐BO‐4F) interfaces of OSCs, thus improving device performance. The ALD‐Al2O3 thin layers on ZnO significantly improved its surface morphology, which led to the decreased work function of ZnO and reduced recombination losses in devices. The simultaneous increase in open‐circuit voltage (VOC), short‐circuit current density (JSC) and fill factor (FF) were achieved for the OSCs incorporated with ALD‐Al2O3 interlayers of a certain thickness, which produced a maximum PCE of 16.61%. Moreover, the ALD‐Al2O3 interlayers had significantly enhanced device stability by suppressing degradation of the photoactive layers induced by the photocatalytic activity of ZnO and passivating surface defects of ZnO that may play the role of active sites for the adsorption of oxygen and moisture. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of our study was to investigate the clinical significance and prognostic role of the systemic immune‐inflammation index (SII) in patients who underwent surgical resection for nonfunctioning pancreatic neuroendocrine tumors (pNETs). Methods: We conducted a retrospective analysis of 364 patients with nonfunctioning pNETs. The association between the SII level and clinical parameters was investigated. The receiver operating characteristic (ROC) curve was used to calculate the optimal SII value. Cox proportional hazard analysis was performed to evaluate the prognostic factors. Results: Our study included 364 patients with nonfunctioning pNETs who underwent surgery. The median age was 51.0 (43.0, 59.3), and 164 (45.1%) were male. The optimal threshold of SII determined by ROC analysis was 523.95. Higher SII levels were significantly associated with older age (p = 0.001), sex (p = 0.011), tumor size (p = 0.032), and tumor grade (p = 0.002). Recurrence was observed in 70 (19.2%) patients following a median follow‐up of 98 months. Univariate analysis showed that higher SII (p < 0.0001), tumor size >4 cm (p = 0.015), and G2/G3 grade (p = 0.002) were significantly associated with disease‐free survival (DFS). Multivariate analysis revealed that higher SII (HR: 7.35; 95% CI: 3.44, 15.70; p < 0.0001) and G2/G3 grade (HR: 3.11; 95% CI: 1.42, 6.82; p = 0.005) remained significantly associated with tumor recurrence. Furthermore, 46 (12.6%) patients died during the follow‐up. Higher SII (HR: 8.43; 95% CI: 3.19, 22.72; p < 0.0001) and G2/G3 grade (HR: 3.16; 95% CI: 1.01, 9.86; p = 0.048) were independent predictors of overall survival (OS) by multivariate analysis. Conclusion: In conclusion, our study revealed that a higher SII level was associated with tumor‐related features (larger tumor size and advanced grade) and subsequent shorter DFS and OS in patients with nonfunctioning pNETs. These results indicated that the SII could serve as an efficient prognostic biomarker for nonfunctioning pNETs. [ABSTRACT FROM AUTHOR]

This study aims to comprehensively compare the effects of unicondylar knee arthroplasty (UKA) and high tibial osteotomy (HTO) on wound infection and pain in patients with medial knee osteoarthritis. A computerized search was conducted in Embase, PubMed, Google Scholar, China National Knowledge Infrastructure, Cochrane Library and Wanfang databases, from database inception to October 2023, for studies comparing UKA and HTO for medial knee osteoarthritis. Studies selection, data extraction and study quality evaluation were independently conducted by two researchers. Stata 17.0 software was employed for data analysis. Overall, 10 studies involving 870 patients with medial knee osteoarthritis were included. It was found that the UKA group had significantly lower wound visual analogue scale scores compared to the HTO group (SMD = ‐0.53, 95%CI: −0.87 to −0.20, p < 0.001). The incidence of wound infection in the UKA group was higher than in the HTO group (OR = 1.92, 95%CI: 0.65–5.69, p = 0.240), and the incidence of complications was lower (OR = 0.89, 95%CI: 0.52–1.54, p = 0.684), though these differences were not statistically significant. This study indicates that UKA is effective in alleviating postoperative wound pain in medial knee osteoarthritis. However, the rates of postoperative wound infection and complications are comparable to those of HTO. Clinicians should consider factors such as patient age and disease severity in making individualized treatment decisions. [ABSTRACT FROM AUTHOR]

Due to the limited hardware available in virtual reality, such as VR controllers or simple motion capture devices, users will need more tactile feedback, like the weight of virtual objects. Pseudo‐tactile feedback, such as the control display (C/D) ratio manipulation method, is considered a standard method to simulate weight perception. In past studies, this method was basically used in a static environment, and the C/D ratio was usually determined initially. Can this method still work if the C/D ratio changes in dynamic usage scenarios? In a series of experiments, we tried to answer this question. We proved that the dynamic change of C/D ratio could simulate the weight change and improve the sense of embodiment through another hand redirection method. [ABSTRACT FROM AUTHOR]

Using a screen‐printing techniques is thought to be a good candidate for simplified, cost‐effective, reliable, and scalable fabrication of fully printed perovskite solar cells (PSCs) for industrialization. Nevertheless, the screen‐printing of perovskite film has not been realized until recently. This group finished the work using ionic liquid methylamine acetate (MAAc) as pure solvent. However, the space‐confining effect during the perovskite crystallization in mesoporous impeded the escape of bottom MAAc molecules, which leads to the poor crystalline quality of the screen‐printed film. In this work, ionic liquid methylamine propionate (MAPa) with stronger coordination is introduced as a co‐solvent to promote the escape of MAAc molecules by forming the solvent volatilization channels in a confined mesoporous structure, which results in the complete MAAc volatilization and high filling degree of perovskite crystals inside the mesoporous structure. Also, MAPa promotes the vertical growth of perovskite crystals and coordinates with unbonded Pb2+ on the perovskite surface, leading to efficient charge transport and interfacial band alignment of the screen‐printed film. Finally, fully screen‐printed PSCs yields a champion power conversion efficiency (PCE) of ≈17%, which is the record value for fully screen‐printed PSCs. Moreover, the unencapsulated device shows robust operational stability that maintains >85.3% of initial PCE (25%RH and 25 °C) under continuous illumination at the maximum power point after 250 h. [ABSTRACT FROM AUTHOR]

In wearable robotics, soft actuation principles have been increasingly explored and tested due to their safety and comfort in human–robot interactions. Herein, a braided flat‐tube artificial muscle (BFAM) is presented. BFAMs are fabricated by braiding cotton threads together with an inexpensive lay‐flat tube (LFT) in a specific conform‐to‐LFT weaving method. They generate uniaxial contractions when powered by compressed fluids. The basic structure and working mechanism of the proposed BFAM are explained, and a quasistatic model is also developed. A comparison with other fluidic driven soft actuators is made and tabulated. Based on experimental studies, the proposed BFAM can contract close to 30% and yield force outputs more than 150 times their weight at an air pressure of 0.12 MPa. BFAM can be braided with multiple layers of flat tube without large increase of size. Experimental studies have shown that more layers of flat tube give a larger strain and output force up to four layers, beyond which layer increase does not yield visible improvement in strain and output force. Finally, potential applications of BFAM to arm joint actuations are illustrated to show its easy fitting to wearable robotics. [ABSTRACT FROM AUTHOR]

As a key contender in the field of photovoltaics, third‐generation thin‐film perovskite solar cells (PSCs) have gained significant research and investment interest due to their superior power conversion efficiency (PCE) and great potential for large‐scale production. For commercialization consideration, low‐cost and scalable fabrication is of primary importance for PSCs, and the development of the applicable film‐forming techniques that meet the above requirements plays a key role. Currently, large‐area perovskite films are mainly produced by printing techniques, such as slot‐die coating, inkjet printing, blade coating, and screen‐printing. Among these techniques, screen printing offers a high degree of functional layer compatibility, pattern design flexibility, and large‐scale ability, showing great promise. In this work, the advanced progress on applying screen‐printing technology in fabricating PSCs from technique fundamentals to practical applications is presented. The fundamentals of screen‐printing technique are introduced and the state‐of‐the‐art studies on screen‐printing different functional layers in PSCs and the control strategies to realize fully screen‐printed PSCs are summarized. Moreover, the current challenges and opportunities faced by screen‐printed perovskite devices are discussed. This work highlights the critical significance of high throughput screen‐printing technology in accelerating the commercialization course of PSCs products. [ABSTRACT FROM AUTHOR]

Mixed‐dimensional engineering of perovskite material has been demonstrated as a facile and promising strategy to improve both photovoltaic performance and long‐term stability of perovskite solar cells (PSCs). In this study, we report an in‐plane preferred orientation of 1D perovskite induced by an ionic liquid (IL) of 1‐(3‐cyanopropyl)‐3‐methylimidazolium chloride (CPMIMCl) for the first time via sequential deposition approach, leading to a mixed dimensional perovskite thin films. The generated one‐dimensional (1D) CPMIMPbI3 with in‐plane orientation resides at the grain boundaries of three‐dimensional (3D) perovskite can be appreciably observed from the morphology level, leading to creation of high‐quality films with large grain size with more efficient defect passivation. Moreover, the dispersion of IL in the bulk phase of perovskite material allows for the formation of 1D perovskite for multiple level passivation to inhibit non‐radiative recombination and optimize carrier transport. This IL engineering strategy not only yields a mixed‐dimensional perovskite heterostructure with in‐plane orientation 1D perovskite nano‐rods but also significantly improves the opto‐electronic property with suppressed trap states. As a result, the CPMIMCl‐treated PSCs show an enhanced photovoltaic performance with a champion power conversion efficiency (PCE) up to 24.13%. More importantly, benefiting from the hydrophobicity of formed 1D perovskite and defects suppression, the corresponding PSC demonstrates an excellent long‐term stability and maintain 97.1% of its pristine PCE at 25°C under 50% RH condition over 1000 h. This research provides an innovative perspective for employing the low dimensional engineering to optimize the performance and stability of photovoltaic devices. [ABSTRACT FROM AUTHOR]

Pneumatic and tendon‐driven actuators are widely used in soft robotic glove design. Tendon‐driven robotic gloves are generally better in controllability, dexterity, and force output, but they are less comfortable than pneumatic ones. Most soft gloves focus on only one actuation mode where either motor‐driven tendon or pump‐driven pneumatic transmission is used. Herein, a double‐acting soft actuator (DASA) that provides both tendon‐driven flexion and pneumatic extension of fingers by a single motor is presented. This is achieved by a smart pulley and bellow system. The kinematic model of the tendon‐driven flexion and the torque model of the fabric‐based pneumatic extension actuator (FPEA) are developed to analyze the DASA performance. The bending angle of the index finger actuated by the tendon and the FPEA extension torque of a joint are characterized by experimental studies. A cycle test of the DASA is conducted 3000 times, demonstrating its high repeatability. A prototype soft glove (68 g) based on the proposed DASA with a control box (835 g) is fabricated to demonstrate finger flexion and extension assistance. Based on electromyography signals, the performance of the robotic glove is evaluated by a squeezing sponge test. [ABSTRACT FROM AUTHOR]

Limited to the structure of traditional light‐emitting devices, electronic devices that can directly convert machine language into human visual information without introducing any back‐end circuit are still not easy to achieve. Based on a specially designed three‐phase co‐planar electrode structure, a new type of three‐phase alternating current driven organic light‐emitting device with the integration of emission and control functions, full‐color tunability and simple device structure is demonstrated in this study. We integrate the light‐emitting function of color‐tunable light‐emitting devices and the switching of three triodes in a single three phase organic light‐emitting device. The state control of luminous color and luminance intensity merely requires the introduction of a kind of machine language, that is an easy‐to‐program 6‐bit binary number coded digital signals. The color adjustable area covers 66% of the color triangle of the National Television System Committee. Such simple and easy‐to‐integrate light‐emitting system has great potential applications in the next‐generation man‐machine interface. [ABSTRACT FROM AUTHOR]

Two‐dimensional Ruddlesden−Popper (2DRP) perovskites have attracted intense research interest for optoelectronic applications, due to their tunable optoelectronic properties and better environmental stability than their three‐dimensional counterparts. Furthermore, high‐performance photodetectors based on single‐crystal and polycrystalline thin‐films 2DRP perovskites have shown great potential for practical application. However, the complex growth process of single‐crystal membranes and uncontrollable phase distribution of polycrystalline films hinder the further development of 2DRP perovskites photodetectors. Herein, we report a series of high‐performance photodetectors based on single‐crystal‐like phase‐pure 2DRP perovskite films by designing a novel spacer source. Experimental and theoretical evidence demonstrates that phase‐pure films substantially suppress defect states and ion migration. These highly sensitive photodetectors show Ilight/Idark ratio exceeding 3 × 104, responsivities exceeding 16 A/W, and detectivities exceeding 3 × 1013 Jones, which are higher at least by 1 order than those of traditional mixed‐phase thin‐films 2DRP devices (close to the reported single‐crystal devices). More importantly, this strategy can significantly enhance the operational stability of optoelectronic devices and pave the way to large‐area flexible productions. [ABSTRACT FROM AUTHOR]

Organic–inorganic perovskite solar cells (PSCs) have achieved great attention due to their expressive power conversion efficiency (PCE) up to 25.7%. To improve the photovoltaic performance of PSCs, interface engineering between the perovskite and hole transport layer (HTL) is a widely used strategy. Following this concept, benzyl trimethyl ammonium chlorides (BTACls) are used to modify the wet chemical processed perovskite film in this work. The BTACl‐induced low dimensional perovskite is found to have a bilayer structure, which efficiently decreases the trap density and improves the energy level alignment at the perovskite/HTL interface. As a result, the BTACl‐modified PSCs show an improved PCE compared to the control devices. From device modeling, the reduced charge carrier recombination and promoted charge carrier transfer at the perovskite/HTL interface are the cause of the open‐circuit (Voc) and fill factor (FF) improvement, respectively. This study gives a deep understanding for surface modification of perovskite films from a perspective of the morphology and the function of enhancing photovoltaic performance. [ABSTRACT FROM AUTHOR]

Perovskite nanocrystals (PNCs) with unique and excellent optical properties have emerged as appealing luminescent materials in optoelectronic fields. However, high temperature processing, complicated procedures, and the use of toxic solvents are typically involved in the preparation of PNCs and their related optoelectronic devices. In this study, a one‐step method is developed for the preparation of flexible photoluminescence gel based on PNCs at ambient conditions, which is a promising alternative to the current PNCs preparation strategy in terms of experimental friendliness, ease of production, and the potential for flexible devices. Acrylic acid (AA) is used for in situ crystallization of PNCs. The interaction between H+ of AA and perovskite‐solvent complex determines the nucleation and growth of PNCs. This crystallization mechanism is systematically studied by varying acid category, adjusting solvent kind, and regulating the ratio of PNCs and gels. To give a proof of practicability, flexible free‐standing PNCs‐gel composites with excellent luminescent and mechanical properties are prepared with the AA treatment. Moreover, the PNCs‐gel shape can be customized, which greatly expands the structural flexibility and functionalities of fabricated devices. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have drawn substantial interest in optoelectronic devices in the past decade. Perovskite/electrode contacts are crucial for constructing high‐performance charge‐transporting‐layer‐free perovskite devices, such as solar cells, field‐effect transistors, artificial synapses, memories, etc. Many studies have evidenced that the perovskite layer can directly contact the electrodes, showing abundant physicochemical, electronic, and photoelectric properties in charge‐transporting‐layer‐free perovskite devices. Meanwhile, for perovskite/metal contacts, some critical interfacial physical and chemical processes are reported, including band bending, interface dipoles, metal halogenation, and perovskite decomposition induced by metal electrodes. Thus, a systematic summary of the role of metal halide perovskite/electrode contacts on device performance is essential. This review summarizes and discusses charge carrier dynamics, electronic band engineering, electrode corrosion, electrochemical metallization and dissolution, perovskite decomposition, and interface engineering in perovskite/electrode contacts‐based electronic devices for a comprehensive understanding of the contacts. The physicochemical, electronic, and morphological properties of various perovskite/electrode contacts, as well as relevant engineering techniques, are presented. Finally, the current challenges are analyzed, and appropriate recommendations are put forward. It can be expected that further research will lead to significant breakthroughs in their application and promote reforms and innovations in future solid‐state physics and materials science. [ABSTRACT FROM AUTHOR]

CsPbI3 is attractive for efficient and cost‐effective red perovskite light‐emitting diodes (PeLEDs), but its black phases still suffer from the metastable structure. The incorporation of large‐size organic cations has been widely used to construct quasi‐2D perovskites to stabilize the black phases. However, the multiple‐phase quasi‐2D perovskites usually show abundant interface defects and enhanced Auger recombination, leading to the low luminance and serious efficiency roll‐off in PeLEDs. Herein, highly efficient red PeLEDs are demonstrated with high luminance and low efficiency roll‐off realized by manipulating the crystallization kinetics of phenethylamine bromide (PEABr) incorporated CsPbI3. PEABr‐CsPbI3 nanocrystal films with much larger and more oriented β‐CsPbIxBr3‐x grains are successfully obtained through appropriately increasing PbI2 content and coordinating with anti‐solvent treatment. The carrier recombination dynamics investigations reveal that the trap‐assisted recombination and Auger recombination are greatly reduced in the passivation‐free PEABr‐CsPbI3 films by rational crystallization regulation. A peak external quantum efficiency (EQE) up to 19.6% is achieved in the red PeLEDs with a stable emission peak at 672 nm, which is maintained as high as 17.2% at a high luminance of over 1000 cd m−2. This study could shed light on modulating the crystallization kinetics of pervoskites to optimize carrier recombination dynamics toward high performance PeLEDs. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI3 perovskites have shown great promise in photovoltaic devices owing to their high theoretical power conversion efficiency (PCE) and excellent thermal stability compared to their organic–inorganic counterparts. However, due to the poor phase stability of CsPbI3 perovskite under ambient conditions, it is still challenging to fabricate the efficient and stable all‐inorganic CsPbI3‐based perovskite solar cells (PSCs). Herein, a ternary halogen doping strategy is demonstrated to improve the quality and stability of air‐processed all‐inorganic CsPbI3 perovskite films, where CsBr and PbCl2 are introduced as halide sources. Br and Cl are found to insert into the crystal lattice of the CsPbI3 perovskite to improve its phase stability while regulating the crystallization process to improve its film morphology with reduced surface roughness and suppressed defect density. After optimizing the doping content of Br and Cl, the air‐fabricated PSC device based on ternary halogen doping yields a champion PCE of 17.51% with improved working stability, which retains over 80% of the initial PCE after continuous illumination for 2400 h. This work highlights the key role of halide‐doping in improving film quality and phase stability of air‐fabricated all‐inorganic perovskite, which is expected to promote the development of low‐cost and large‐scale production of all‐inorganic PSCs. [ABSTRACT FROM AUTHOR]

Formamidinium lead triiodide (FAPbI3) with a narrow bandgap, broad light absorption spectra, and high thermal stability has emerged as one of the promising active materials for perovskite solar cells. To date, the certified power conversion efficiency of FAPbI3‐based solar cells has reached 25.7%, comparable with that of monocrystalline silicon solar cells (26.7%). However, FAPbI3 tends to form an undesirable metastable nonperovskite phase (α‐FAPbI3), which is the most fatal issue for the commercialization development of FAPbI3‐based perovskite solar cells. Many efforts are committed to stabilizing the α‐FAPbI3 phase. In this review, the strategies involving composition engineering in A‐site (including double‐cation, triple‐cation, quadruple‐cation systems) and X‐site ions (halides and pseudohalides) to stabilize FA‐based perovskites are summarized. To realize higher efficiencies and avoid the increase in bandgap and phase segregation issue induced by the multicomponent elements, the corresponding strategies for preparing a pure α‐FAPbI3 perovskite with various functional materials are discussed. Moreover, the perovskite crystal redissolution strategy to prepare perovskite films with high purity, precise stoichiometric ratio, high crystallinity, ideal crystal orientation, and low defect density is described for highly efficient FAPbI3‐based perovskite solar cells. Finally, the perspective for future research directions toward highly reproducible and large‐area FAPbI3‐based photovoltaics is raised. [ABSTRACT FROM AUTHOR]

Tin‐based perovskites show great potential in photovoltaic applications, and the development of the corresponding solar cells (PSCs) has made exciting progress during the past few years. However, owing to the high Lewis acidity and easy oxidation of Sn2+, Sn‐based perovskite films suffer from fast crystallization and easy formation of vacancy defects with low activation energy during the solution film‐forming process, resulting in poor film quality and inferior device performance. Therefore, an in‐depth understanding and rational control of film‐forming dynamics of Sn‐based perovskites is essential to improve the photovoltaic performance of their PSCs. In this review, the state‐of‐the‐art developments in crystallization dynamics control for Sn‐based perovskites and their impact on the photovoltaic performance of PSCs are systematically summarized. The review begins with the introduction of fundamentals and key difficulties for the control of the crystallization process of Sn‐based perovskites. Then, the advanced strategies that focus on regulating the crystallization process of Sn‐based perovskite films are comprehensively reviewed, including solvent engineering, additive engineering, cation engineering, and film‐forming technique engineering. Finally, future perspectives and research directions, regarding the smart control of crystallization dynamics of Sn‐based perovskite film, are discussed towards high‐performance and stable Sn‐based PSCs. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid Pb halide perovskites have gained much attention as the most promising next generation photovoltaics, and the certificated power conversion efficiency of perovskite solar cells (PSCs) has recently reached 25.5%. For the typical solution‐processed film, the features of solutes in the precursor solution greatly influence the characteristics of the deposited film. While for Pb‐based perovskites, PbI6 octahedral is the key component of the perovskite framework, and thus the Pb source particularly plays a significant role in determining the crystallization, structural, and optoelectronic properties of the solution‐processed perovskite film. In this review, the state‐of‐the‐art studies that focus on disclosing the key role of Pb source in the performance improvement of PSCs are systematically summarized. In addition, a comprehensive discussion on the effect of various Pb sources (e.g., Pb halides, Pb salts, Pb chalcogens, metallic Pb, and recycled Pb compounds) on the crystallization kinetics and photovoltaic characteristics of perovskite film is given. Also, the significant role of Pb source in producing large‐scale PSCs in a controllable and sustainable manner is highlighted. This review is expected not only to put steps forward for the future commercialization of PSCs, but also to inspire more ideas in many other optoelectronic devices regarding raw material engineering. [ABSTRACT FROM AUTHOR]

Organic–inorganic halide perovskite (OIHP) solar cells hold a great promise for commercial breakthrough since their power conversion efficiency has been pushed beyond the mark of 25%, making them capable of competing with traditional crystalline silicon solar cells. The key to achieve efficient and stable perovskite solar cells is inherently related to the film morphology. The understanding of the kinetic processes of film formation and degradation opens up possibilities to tailor the film morphology via the regulation of precursor and processing parameters. In situ grazing‐incidence X‐ray scattering (GIXS) techniques allow for tracking the morphology evolution of thin films at different length scales and with high temporal resolution. In this review, the selected examples for application of in situ grazing‐incidence wide‐angle X‐ray scattering and grazing‐incidence small‐angle X‐ray scattering techniques to the growth and stability of OIHPs are summarized after a brief introduction to both techniques, highlighting particularly the morphological evolution of perovskite films over time. Then the correlated mathematical models are reviewed to give a toolbox for analyzing the mechanisms of film formation and degradation. Thus, an overview on the in situ GIXS methods is linked to the research of OIHP kinetics. [ABSTRACT FROM AUTHOR]

2D/3D mixed tin (Sn)‐based perovskites serving as excellent active layers possess a potential for enhancing film/device stabilities, open‐circuit voltage, and power conversion efficiency (PCE) of perovskite solar cells (PSCs). Unfortunately, the poor morphology and low film coverage of these 2D/3D perovskites jeopardize their device performance and stability. Herein, doping of hydroxyl‐rich d‐sorbitol into hole transport layer poly(3,4‐ethenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) can effectively address the PEDOT:PSS/perovskite interfacial issues. The multihydroxyl groups from d‐sorbitol can sufficiently anchor iodide ions ([SnI6]4− or free I−) of PEA0.1(FA0.75MA0.25)0.9SnI3 perovskite via hydrogen bond, which not only introduces more nucleation sites with improved crystallinity along the preferential crystal orientations, but also reduces the trap states' density and suppresses the iodide ions' migration. In the meanwhile, the content of SnI2 is reduced in the resulting perovskite films. All of these are conducive to form compact and smooth high‐quality perovskite films with less traps and enhanced stability. Benefitting from these, an inverted PSC with a champion PCE of 10.46% and a lifetime of 700 h (25% attenuation in N2) is eventually achieved. This work provides a promising approach to manufacture highly efficient and stable Sn‐based PSCs based on 2D/3D mixed perovskites. [ABSTRACT FROM AUTHOR]

Pb‐based perovskite solar cells (PSCs) have shown great potential in next‐generation photovoltaics. However, the toxicity of Pb remains a big concern. Partial replacement of Pb with Sn is shown to reduce the toxicity of PSCs without considerably compromising the device performance. Currently, Sn–Pb single‐junction PSCs have realized a champion power conversion efficiency (PCE) of 21.7%, whereas all perovskite tandem PSCs with a Pb–Sn device as the bottom cell have achieved a PCE of 25.5%. However, the fabrication process of Sn–Pb PSCs is still not ecofriendly due to the use of hazardous organic solvents and antisolvents. Herein, for the first time, a one‐step antisolvent‐free method is developed to fabricate a high‐quality Sn–Pb perovskite film using methylammonium acetate (MAAc) ionic liquid as a green solvent. The crucial effects of multiple organic halides (MOHs) on the crystallization process and characteristics of the Sn–Pb film are comprehensively investigated. After optimizing the film fabrication parameters, PSCs with a champion PCE of 15.42% can be achieved. Moreover, the device exhibits robust stability that shows negligible PCE loss after being stored in N2 for 720 h. A new avenue to promote the ecofriendly fabrication of efficient Sn–Pb PSCs is opened up. [ABSTRACT FROM AUTHOR]

The aim of this meta‐analysis was to review systematically and to identify the relationship between the severity and location of white matter hyperintensities (WMHs) and the degree of cognitive decline in patients with Parkinson's disease (PD). We searched the PubMed, EMBASE, Web of Science, Ovid, and Cochrane Library databases for clinical trials of the severity and location of WMHs on the degree of cognitive impairment in PD through October 2020. We conducted the survey to compare the association of WMH burden in patients with PD with mild cognitive impairment (PD‐MCI) versus those with normal cognition (PD‐NC) and in patients with PD with dementia (PDD) versus those with PD without dementia (PD‐ND). Nine studies with PD‐MCI versus PD‐NC and 10 studies with PDD versus PD‐ND comparisons were included. The WMH burden in PD‐MCI patients was significantly different compared to that in PD‐NC patients (standard mean difference, SMD = 0.39, 95% CI: 0.12 to 0.66, p = 0.005), while there was no correlation shown in the age‐matched subgroup of the comparison. In addition, PDD patients had a significantly higher burden of WMHs (SMD = 0.8, 95% CI: 0.44 to 1.71, p < 0.0001), especially deep white matter hyperintensities (SMD = 0.54, 95% CI: 0.36 to 0.73, p < 0.00001) and periventricular hyperintensities (SMD = 0.70, 95% CI: 0.36 to 1.04, p < 0.0001), than PD‐NC patients, regardless of the adjustment of age. WMHs might be imaging markers for cognitive impairment in PDD but not in PD‐MCI, regardless of age, vascular risk factors, or race. Further prospective studies are needed to validate the conclusions. [ABSTRACT FROM AUTHOR]

Due to the continuous development and advances in the Internet of Things, wireless sensors, actuators for human−interactive machines, and indoor low‐power devices require a continuous supply of energy. Photovoltaic cells working under indoor light are suitable candidates for charging these devices because of their high voltages (up to 5 V), low costs, and environmental friendliness. Herein, the research on organic photovoltaic, dye‐sensitized, and perovskite cells in indoor photovoltaic applications with respect to the active layer, modified layer, and preparation process is summarized. The performance enhancement of indoor photovoltaic cells is outlined, including photoactive material selection, bandgap optimization, modification layer function, and device structure design, followed by the prospects and challenges of future developments in indoor photovoltaic cells. With this review an important perspective for the advancement of indoor photovoltaics is offered. [ABSTRACT FROM AUTHOR]

Solution‐processed tin oxide (SnO2) is ubiquitously used as the electron transport layer (ETL) in perovskite solar cells, while the main concerns related to the application of SnO2 nanoparticles are the self‐aggregation potential and infeasible energy level adjustment, leading to inhomogeneous thin films and mismatched energy alignment with perovskite. Herein, a novel route is developed by adding a functional titanium diisopropoxide bis(acetylacetonate) (TiAcAc) molecule, comprising TiO44– core, functional CO, and long alkene groups, into the SnO2 nanoparticle solution, to optimize the electronic transfer property of SnO2 for efficient perovskite solar cells. It is found that the TiO44– can be used to tune the electronic property of the SnO2 layer, and the long alkenes can act as a stabilizer to avoid the nanoparticle aggregation and electronic glue among the SnO2 nanoparticles in the eventual nanoparticulate thin film, enhancing its homogeneity and conductivity. Furthermore, the residual CO groups on the ETL surface can strongly associate with the Pb2+ and improve the interface intimacy between the ETL and perovskite. As a result, the efficiency of perovskite solar cells can be boosted from 18% to above 20% with significantly reduced hysteresis by employing SnO2‐TiAcAc as electron transport layer, indicating a great potential for efficient perovskite solar cells. [ABSTRACT FROM AUTHOR]

The past decade has witnessed the great success achieved by metal halide perovskites (MHPs) in photovoltaic and related fields. However, challenges still remain in further improving their performance, as well as, settling the stability issue for future commercialization. Recently, MHP/2D material heterostructures that combining MHPs with the low‐cost and solution‐processable 2D materials have demonstrated unprecedented improvement in both performance and stability due to the distinctive features at hetero‐interface. The diverse fabrication techniques of MHPs and 2D materials allow them to be assembled as heterostructures with different configurations in a variety of ways. Moreover, the large families of MHPs and 2D materials provide the opportunity for the rational design and modification on compositions and functionalities of MHP/2D materials heterostructures. Herein, a comprehensive review of MHP/2D material heterostructures from syntheses to applications is presented. First, various fabrication techniques for MHP/2D material heterostructures are introduced by classifying them into solid‐state methods and solution‐processed methods. Then the applications of MHP/2D heterostructures in various fields including photodetectors, solar cells, and photocatalysis are summarized in detail. Finally, current challenges for the development of MHP/2D material heterostructures are highlighted, and future opportunities for the advancements in this research field are also provided. [ABSTRACT FROM AUTHOR]

Due to the impressive optoelectronic properties, metal–halide perovskites (MHPs) have drawn much attention in the field of next‐generation photovoltaics, and perovskite solar cells (PSCs) based on MHPs as light absorbers have reached a certified power conversion efficiency (PCE) of 25.5% in 2020. Despite the great progress, it is still challenging to fabricate high‐quality MHP films. Due to the "soft" ionic nature of MHPs, their polycrystalline films suffer from inevitable residual strain, which is found to not only be fatal to photovoltaic performance of PSCs, but also seriously accelerate the degradation of MHP film. As a result, understanding of strain in MHPs and the key role of strain engineering in improving the photovoltaic performance of PSCs have recently been extensively investigated. Herein, the recent progress of strain engineering in MHPs and their PSCs is systematically summarized. First, the origin of strain in MHPs and the impact of strain on the optoelectronic characteristics of MHPs are carefully discussed. Thereafter, the up‐to‐date studies focusing on strain engineering in PSCs are comprehensively reviewed. At last, the current challenges and future prospects in this field are highlighted. [ABSTRACT FROM AUTHOR]

Interfacial engineering is essential for facilitating carrier separation, charge extraction, and enhancing the stability in organic–inorganic perovskite solar cells (PSCs). Herein, a facile and effective method is demonstrated not only to tune the electronic performance of electron transporting layer (ETL) but also to passivate the defects at the interface between the ETL and perovskite. On the top of the tin(IV) oxide (SnO2) ETL, butylammonium chloride (BACl) and lead(II) iodide (PbI2) are introduced as interface to modify the ETL/perovskite interface. The PSCs with interface modified exhibit a power conversion efficiency (PCE) of 21.15%, compared to 18.33% for the device without interface modified. Such enhancement in efficiency is mainly attributed to a better energy band alignment, and the quality of perovskite films is improved through the interface modification, thus enhancing photogenerated charge extraction and leading to low charge carrier recombination at the interface of ETL/perovskite. Furthermore, the device with interface modified exhibits significant stability. This work provides an alternative strategy on the ETL/perovskite interface to obtain highly stable and efficient PSCs. [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitors (ICIs) are widely used in oncology for their favourable antitumor efficacy. ICI therapy is associated with a unique toxicity profile known as immune‐related adverse events (irAEs). One such irAE is ICI‐related diabetes mellitus (DM), which is relatively uncommon but can become extremely severe, leading to irreversible impairment of β‐cells, and even lead to death if not promptly recognised and properly managed. The precise mechanisms of ICI‐related DM are not well understood. In this review, we summarise the clinical characteristics, pathophysiology, and management of this adverse effect caused by ICI therapy. Deeper investigation of ICI‐related DM may contribute to elucidate the molecular mechanisms of classical type 1 DM. [ABSTRACT FROM AUTHOR]

The instability of organic cations in lead halide perovskite materials is a major obstacle for the commercial breakthrough of perovskite photovoltaics due to desorption of organic cations during the thermal annealing and device operation. Herein, a novel strategy is reported to improve the performance and stability of organic halide perovskite solar cells containing organic cations by adding a small amount of the ionic liquid methylammonium difluoroacetate (MA+DFA−). Nuclear magnetic resonance and Fourier‐transform infrared spectroscopy measurements show that MA+DFA− can anchor the organic cations via hydrogen bonding and enhance the Pb–O interaction in perovskite precursors, leading to the retardation of the perovskite crystallization and improved stability of the perovskite precursor solution. Dynamic light scattering and scanning electron microscopy verify the defect‐passivation effect of MA+DFA− on the perovskite precursors and films. The passivated perovskite film shows superior photo carrier dynamics as investigated by time‐resolved photoluminescence and transient absorption spectra. Moreover, the hydrogen bonding of the perovskite with MA+DFA− imparts excellent ambient and thermal stability to the film as revealed by X‐ray diffraction measurements. As a result, devices with a high efficiency of 21.46% and excellent stability over 180 days in nitrogen atmosphere at room temperature are achieved with the ionic liquid. [ABSTRACT FROM AUTHOR]

Recently, the power conversion efficiency (PCE) of perovskite solar cells (PSC) based on organic‐inorganic hybrid Pb halide perovskites has reached 25.2 %. However, the toxicity of Pb has still been a main concern for the large‐scale commercialization of Pb‐based PSCs. Efforts have been made during the past few years to seek eco‐friendly Pb‐free perovskites, and it is a growing consensus that Sn is the best choice as Pb alternative over any other Pb‐free metal elements. Among Sn‐based perovskites, all‐inorganic cells are promising candidates for PSCs owing to their more suitable bandgap, better stability, and higher charge mobility compared to the organic‐inorganic hybrid counterparts. However, the poor phase stability of all‐inorganic Sn‐based perovskites (AISPs) and low PCE of their PSCs are most challenging in the field at present. Herein, recent developments on PSCs based on AISPs, including CsSnX3 and Cs2SnX6 (X=Br, I), are comprehensively reviewed. Primarily, the intrinsic characteristics of the two AISPs are overviewed, including crystallographic property, band structure, charge carrier property, and defect property. Sequentially, state‐of‐the‐art progress, regarding the photovoltaic application of AISPs as light absorber, is summarized. At last, current challenges and future opportunities of AISP‐based PSCs are also discussed. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have been widely applied in optoelectronic fields, but their poor stability hinders their actual applications. A perovskite–zeolite composite was synthesized via in situ growth in air from aluminophosphate AlPO‐5 zeolite crystals and perovskite nanocrystals. The zeolite matrix provides quantum confinement for perovskite nanocrystals, achieving efficient green emission, and it passivates the defects of perovskite by H‐bonding interaction, which leads to a longer lifetime compared to bulk perovskite film. Furthermore, the AlPO‐5 zeolite also acts as a protection shield and enables ultrahigh stability of perovskite nanocrystals under 150 °C heat stress, under a 15‐month long‐term ambient exposure, and even in water for more than 2 weeks, respectively. The strategy of in situ passivation and encapsulation for the perovskite@AlPO‐5 composite was amenable to a range of perovskites, from MA‐ to Cs‐based perovskites. Benefiting from high stability and photoluminescence performance, the composite exhibits great potential to be virtually applied in light‐emitting diodes (LEDs) and backlight displays. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) AA′n−1MnX3n+1 type halide perovskites incorporating straight‐chain symmetric diammonium cations define a new type of structure, but their optoelectronic properties are largely unexplored. Reported here is the synthesis of a centimeter‐sized AA′n−1MnX3n+1 type perovskite, BDAPbI4 (BDA=NH3C4H8NH3), single crystal and its charge‐transport properties under X‐ray excitation. The crystal shows a staggered configuration of the [PbI6]4− layers, a band gap of 2.37 eV, and a low trap density of 3.1×109 cm−3. The single‐crystal X‐ray detector exhibits an excellent sensitivity of 242 μC Gyair−1 cm−2 under the 10 V bias (0.31 V μm−1), a detection limit as low as 430 nGyair s−1, ultrastable response current, a stable baseline with the lowest dark current drift of 6.06×10−9 nA cm−1 s−1 V−1, and rapid response time of τrise=7.3 ms and τfall=22.5 ms. These crystals are promising candidates for the next generation of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Pb‐based metal halide perovskites (MHPs) have emerged as efficient light absorbers in third‐generation photovoltaic devices, and the latest certified power conversion efficiency (PCE) of Pb‐based perovskite solar cells (PSCs) has reached 25.2%. Despite great progress, Pb‐based MHPs are affected by toxicity, which hinders their market entry in a potential future large‐scale commercialization effort. Therefore, the exploration of Pb‐free MHPs has become one of the alternative solutions sought in the community. Among all the Pb‐free MHPs, Sn‐based MHPs show great promise owing to their similar or even superior theoretical optoelectronic characteristics. After several years of development, the PCE of Sn‐based PSCs has recently been approaching 10%, with the breakthroughs mainly coming from A‐site cation engineering of Sn‐based MHPs. In this review, the crucial status of A‐site cation engineering strategies in the research of Sn‐based PSCs is highlighted. First, the way the features of A‐site cation influence the structure and characteristics of MHPs is systematically demonstrated. Then, the state‐of‐the‐art developments, focusing on A‐site cation engineering of Sn‐based MHPs, are comprehensively reviewed. Subsequently, the current challenges and opportunities for further boosting the performance of Sn‐based PSCs are discussed. Finally, conclusions and perspectives on the promising Sn‐based optoelectronic devices are discussed. [ABSTRACT FROM AUTHOR]

All‐inorganic lead halide perovskites are promising candidates for optoelectronic applications. However, fundamental questions remain over the component interaction in the perovskite precursor solution due to the limitation of the most commonly used solvents of N,N‐dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Here, we report an interaction tailoring strategy for all‐inorganic CsPbI3−xBrx perovskites by involving the ionic liquid solvent methylammonium acetate (MAAc). C=O shows strong interaction with lead (Pb2+) and N−H⋅⋅⋅I hydrogen bond formation is observed. The interactions stabilize the perovskite precursor solution and allow production of the high‐quality perovskite films by retarding the crystallization. Without the necessity for antisolvent treatment, the one‐step air‐processing approach delivers photovoltaic cells regardless of humidity, with a high efficiency of 17.10 % along with long operation stability over 1500 h under continuous light illumination. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites (OIHPs) have emerged as a novel class of functional materials with applications in solar cells, photodetectors, light‐emitting diodes, and resistive switching memories. Generally, perovskite films are fabricated with toxic solvents and antisolvent technique under inert atmosphere, which limits the commercial applications of OIHP‐based devices. To address this issue, uniform CH3NH3PbBr3 (MAPbBr3) film is fabricated through a facile one‐step spin‐coating method by directly dissolving perovskite precursor in a room‐temperature molten salt methylammonium acetate under air ambient condition. The nonvolatile resistive switching devices based on MAPbBr3 exhibit robust and reproducible write‐once‐read‐many‐times (WORM) memory properties with a large ON/OFF ratio (106), reliable retention properties (104 s), and somewhat ternary resistive characteristic. The conductive filaments in the perovskite thin film are proposed to induce the electrical conductivity switching. Additionally, the MAPbBr3 films can be dissolved rapidly in deionized water within 5 s, showing the transient characteristics. This work demonstrates a new perspective on the perovskite film fabrication and shows the potential application of MAPbBr3 in transient WORM devices. [ABSTRACT FROM AUTHOR]

Perovskite solar cell has made a steady research progress with superior photovoltaic power conversion efficiency (PCE) over 25%. The quality of perovskite film is a key factor affecting device efficiency. Lewis bases such as urea, DMSO and thiourea etc. have been applied in perovskite precursor solutions for one step processing to effectively control the film morphology. Herein, we report urea treatment in a two‐step processing for obtaining high quality methylammonium lead triiodide perovskite (CH3NH3PbI3) film, which is accomplished by immersing the PbI2 film into the mixture solution of urea/methylammonium iodide (MAI). The optimized urea concentration in the MAI solution is 0.4 mg/mL, leading to larger‐sized and better crystalline perovskite grains than that without urea additive. The main function of the urea additive is the formation of the adduct MAI⋅PbI2⋅O=C(NH2)2, retarding the crystallization process of the perovskite film. The steady‐state and time‐resolved photoluminescence measurements revealed that perovskite CH3NH3PbI3 grown using optimized concentration of urea has prolonged carrier lifetime and reduced carrier recombination. Finally, the carbon‐based perovskite solar cells fabricated from the optimal urea concentration of 0.4 mg/mL achieved the enhanced photovoltaic performance with the highest PCE of 13.10% and an average value of 11.34%, in comparison to devices without urea treatment exhibiting an average PCE of only 8.67%. [ABSTRACT FROM AUTHOR]

Overwhelming evidence demonstrates that exosomes, a series of biologically functional small vesicles of endocytic origin carrying a variety of active constituents, especially tumor‐derived exosomes, contribute to tumor progression and metastasis. This review focuses on the specific multifaceted roles of exosomes in affecting sequenced four crucial processes of metastasis, through which cancer cells spread from primary to secondary organs and finally form macroscopic metastatic lesions. First, exosomes modulate the primary tumor sites to assist cancer growth and dissemination. In this part, five main biological events are reviewed, including the transfer of oncogenic constituents, the recruitment and activation of fibroblasts, the induction of angiogenesis, immunosuppression and epithelial‐mesenchymal transition (EMT) promotion. In Step 2, we list two recently disclosed mechanisms during the organ‐specific homing process: the exosomal integrin model and exosomal epidermal growth factor receptor (EGFR)/miR‐26/hepatocyte growth factor (HGF) model. Subsequently, Step 3 focuses on the interactions between exosomes and pre‐metastatic niche, in which we highlight the specific functions of exosomes in angiogenesis, lymphangiogenesis, immune modulation and metabolic, epigenetic and stromal reprogramming of pre‐metastatic niche. Finally, we summarize the mechanisms of exosomes in helping the metastatic circulating tumor cells escape from immunologic surveillance, survive in the blood circulation and proliferate in host organs. [ABSTRACT FROM AUTHOR]

All‐inorganic perovskite nanocrystals have attracted much attention in recent years due to their long stability, spectral tunability, suitable bandgap, long carrier diffusion length and high photoluminescence quantum yield (PLQY). Their excellent optical properties and stability make them suitable candidates for optoelectronic devices. In this review, we first provide an up‐to‐date review on the synthesis of all‐inorganic NCs, such as hot‐injection, room‐temperature, ultrasonication, solvothermal, fast microwave‐assisted and amine‐free methods. In addition, recent research progress of optoelectronic applications in light emitting diodes and solar cells is presented. Finally, we show the new challenges and give suggestions to make a broad range of applications in the near future. All‐inorganic perovskite nanocrystals (NCs) have attracted much attention in recent years due to their long stability, spectral tunability, suitable bandgap, long carrier diffusion length and high photoluminescence quantum yield. Their excellent optical properties and stability make them suitable candidates for optoelectronic devices. In this review, we provide an up‐to‐date review on the synthesis of all‐inorganic NCs and their applications in light emitting diodes and solar cells. Finally, challenges and possible developing directions of all‐inorganic NCs are discussed. [ABSTRACT FROM AUTHOR]