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Efficiency reduction in perovskite solar cells (PSCs) during the magnification procedure significantly hampers commercialization. Vacuum‐flash (VF) has emerged as a promising method to fabricate PSCs with consistent efficiency across scales. However, the slower solvent removal rate of VF compared to the anti‐solvent method leads to perovskite films with buried defects. Thus, this work employs low‐toxic Lewis base ligand solvent N‐ethyl‐2‐pyrrolidone (NEP) to improve the nucleation process of perovskite films. NEP, with a mechanism similar to that of N‐methyl‐2‐pyrrolidone in FA‐based perovskite formation, enhances the solvent removal speed owing to its lower coordination ability. Based on this strategy, p–i–n PSCs with an optimized interface attain a power conversion efficiency (PCE) of 24.19% on an area of 0.08 cm2. The same nucleation process enables perovskite solar modules (PSMs) to achieve a certified PCE of 23.28% on an aperture area of 22.96 cm2, with a high geometric fill factor of 97%, ensuring nearly identical active area PCE (24%) in PSMs as in PSCs. This strategy highlights the potential of NEP as a ligand solvent choice for the commercialization of PSCs. [ABSTRACT FROM AUTHOR]

Ultra‐thin stainless‐steel substrates with excellent water‐oxygen barrier properties and high thermal and electrical conductivities are suitable for the fabrication of lightweight and flexible perovskite solar cells (FPSCs). However, the deposition of dense perovskite films on stainless steel by the solution method is crucial because short circuits caused by perovskite holes are fatal to parallel structures. Herein, a single crystal (SC) is incorporated into the precursor solution to reduce the formation of holes in perovskite films on smooth stainless‐steel substrates. Additionally, a magnetic method is developed based on the properties of stainless steel to fix and fabricate FPSCs nondestructively on ultra‐thin stainless‐steel films with a thickness as low as 5 μm. Furthermore, 4,6‐dimethyl‐2‐mercaptopyrimidine (DMI) was introduced to passivate the surface of the perovskite film, optimizing the contact properties of the perovskite heterojunction and adjusting the energy level of the perovskite/C60 interface. Finally, ultra‐thin FPSCs achieved a champion power conversion efficiency (PCE) of 20.24% on an active area of 1.012 cm2 and a power‐to‐weight ratio over 3000 W kg−1. Moreover, under continuous illumination, the stainless‐steel substrates exhibited better photothermal stability than the polymer substrates. This method provides a basis for the fabrication of lightweight, low‐cost, and large‐area FPSCs. [ABSTRACT FROM AUTHOR]

Objective: Hip fractures are the most common fractures among older adults, with most patients undergoing surgery. The debate regarding the type of anesthetic technique for hip fracture surgery is still ongoing. This meta‐analysis aimed to compare the intraoperative and postoperative outcomes of spinal and general anesthesia in older patients undergoing hip fracture surgery. Methods: Eligible studies that compared the effects of spinal and general anesthesia were systematically searched from PubMed, Embase, and the Cochrane Library until May 27, 2022. The intraoperative and postoperative outcomes of the two anesthesia techniques were compared. Quality assessment, heterogeneity analysis, and publication bias of the studies were also assessed. Results: Nine articles of methodological quality were included in the meta‐analysis. The pooled results revealed that there were significant differences in hypotension (risk ratio [RR] (95% confidence interval [CI]) = 0.81 (0.68, 0.97), p = 0.02) and ephedrine dose (weighted mean difference [WMD] [95%CI] = −20.94 [−37.50, −4.37] mg, p = 0.01) between the spinal and general anesthesia groups. However, no significant differences were observed in the use of ephedrine (RR [95% CI] = 0.77 [0.19, 3.05]), blood loss (WMD [95%CI] = −34.38 [−89.56, 20.80) mL], myocardial infarction (RR [95% CI] = 0.78 [0.31, 1.94] mL), heart failure (RR [95% CI] = 0.87 [0.17, 4.36] mL), stroke (RR [95%CI) = 0.65 [0.22, 1.95] mL), postoperative nausea and vomiting (RR [95% CI] = 0.88 [0.17, 4.35] mL), delirium (RR [95% CI] = 1.08 [0.89, 1.31] mL), and mortality (RR [95% CI] = 1.10 [0.72, 1.68] mL) (all p < 0.05). No publication bias was observed in any of the included studies. Conclusion: Compared to general anesthesia, spinal anesthesia was associated with a lower risk of intraoperative hypotension and lower doses of ephedrine in older patients undergoing hip fracture surgery. [ABSTRACT FROM AUTHOR]

P‐type NiOx films are widely used as hole‐transport layers (HTLs) in p–i–n perovskite solar cells (PSCs) owing to their wide bandgap, stability, and optical transmittance. Chemical bath deposition (CBD) is an effective method for growing metal oxide HTLs. However, NiOx films prepared by the CBD method have pinholes because of their small grain size, which makes it difficult to cover the substrate in all directions, leading to severe carrier recombination at the interface between NiOx and perovskite. Herein, the device efficiency is improved from 18.13% to 22.51% using NiOx prepared by CBD with seed‐assisted growth and Cu‐ion doping as the HTL. The addition of crystal seeds significantly enhances the grain size, resulting in better substrate coverage by the prepared NiOx films. Cu‐ion doping improves the conductivity of the film and enhances its ability to extract holes. In addition, the results confirm that this method is suitable for the manufacturing of large‐area modules and has good reproducibility. This research demonstrates an effective CBD method for creating NiOx films for use in PSCs and offers a new approach for preparing inorganic HTLs using CBD. [ABSTRACT FROM AUTHOR]

Uniform and pinhole‐free functional layers are essential for high‐efficient flexible perovskite solar modules (FPSMs). However, the poor wettability of self‐assembled monolayers (SAMs) with carbazole bodies and phosphonic acid binding groups usually leads to porous large‐area perovskite films. Herein, a layer of nickel oxide nanoparticles is inserted between sputtered nickel oxide and the SAM to increase the surface energy, and thus simultaneously improving the wettability and nucleation of the perovskite during vacuum‐quenching method. Following this strategy, the best flexible perovskite solar cells with an active area of 0.09 cm2 achieve a power conversion efficiency (PCE) of 21.97% under 1 sun illumination. In addition, FPSMs with the same structure exhibit a high fill factor approach 80% and reach a champion PCE of 19.71% on 58.14 cm2 active area and a certified PCE of 18.17% on 61.26 cm2 aperture area, which is the highest recorded PCE to the best knowledge. Furthermore, the optimized interface also enhances the adhesion between hole‐transport layer and perovskite, and the encapsulated device retains 95% of its initial PCE after 1000 cycles under a 2 cm bending radius. [ABSTRACT FROM AUTHOR]

Objective: No consensus has been reached regarding optimal implantation for a syndesmotic screw. Thus, we aimed to explore the feasibility of a reliable and static fibular incisura plane reference for ideal syndesmotic screw placement. Methods: A retrospective review of computed tomography (CT) scans of 42 uninjured adult ankles with foot fractures were analyzed to measure the tibiofibular vertical distance (TFVD) at 2.5 cm proximal to the plafond from August 2016 to June 2017 in our hospital. The patients (20 females, 22 males) were divided into four groups according to their TFVD: 0–1, 1–2, 2–3, and 3–4 mm, and patients in each group were counted. We retrospectively assessed 41 patients (15 females, 26 males) who underwent syndesmotic screw fixation for ankle fractures from December 2015 to June 2020. We performed t‐testing of two independent samples to determine the differences in the angle between the anatomic axis of the syndesmosis and screw axis (AAS) and ankle function using the American Orthopaedic Foot and Ankle Society (AOFAS) score at 3 and 6 months postoperatively between the conventional (20 patients) and K‐wire marker (21 patients) groups. The correlation between the AAS and AOFAS score was analyzed. Results: The TFVD measured 2.23 ± 1.01 mm at 2.5 cm proximal to the plafond, and occurred at 25% of the distance from 2 to 3 mm in 47.6% of the patients. This new technique decreased AAS deformation by 62%, from 13.01° ± 2.84° to 4.89° ± 2.43°, in the conventional group (p < 0.001). At 3 months postoperatively, the AOFAS scores of ankle function were similar in both groups, but it was significantly better in the new group than that of conventional group at the 6‐month follow‐up (p = 0.024). There was a moderate negative correlation between AAS and AOFAS score at 6 months postoperatively (R = −0.684). No obvious complications affecting ankle function were observed in either group postoperatively. Conclusions: Surgeons can accurately place a screw trajectory using the fibular incisura plane as a reliable intraoperative reference. A 1.6‐mm K‐wire placed in the syndesmosis at 2.5 cm proximal to the tibial plafond could act as a static marker of the syndesmotic plane. [ABSTRACT FROM AUTHOR]

Objective: To develop a new approach to intraoperatively identify the presence of coronal plane deformities (both valgus and varus) when treating tibial fractures with closed reduction and intramedullary nail fixation. Methods: A retrospective analysis was conducted by enrolling 33 consecutive patients with tibial fractures who received closed reduction and intramedullary nail fixation from January 2018 to January 2019 at our trauma center. Out of the 33 patients, 23 were males and 10 were females and the average age was 41 years (ranging 22 to 69 years of age). Standard anteroposterior and lateral preoperative radiographs were routinely performed. After intraoperatively inserting the tibial intramedullary nail through the standard entry point, the parallel relationship between the distal horizontal interlocking screw and the tibiotalar joint surface on the anteroposterior fluoroscopy was used to determine the occurrence of valgus or varus deformities of the distal tibial fragment. Radiographic and clinical outcomes were analyzed using the average interval from injury to surgery, the lateral distal tibial angle (LDTA) of the unaffected and affected sides, complications and the Olerud–Molander ankle score. Results: All 33 patients were postoperatively followed for 13 to 25 months (mean 18.7 months). The fractures achieved bone union at an average of 4.3 months (ranging from 3 to 6 months). The total complication rate was 60.6% (20 cases), including four cases that showed deep vein thrombosis, one case showing an infection and delayed union and 15 cases showing slight to moderate anterior knee pain. The postoperative LDTA of the unaffected side measured 87.3° to 89.6 ° (average 88.7° ± 0.8°), and the LDTA of the affected side was 87.5° to 90.4° (average 88.9° ± 1.1°). There was no significant difference between the unaffected and affected sides (t = −1.865, P = 0.068). The intraoperative measurement indicated six cases of valgus angulation and three cases of varus angulation deformities, and all deformities were corrected during surgery. According to the Olerud–Molander ankle score, clinical outcomes demonstrated 22 excellent cases, eight good cases, two fair cases, and one poor case 12 months after surgery. Conclusion: The parallel relationship between the distal horizontal interlocking screw and tibiotalar joint surface on intraoperative anteroposterior films were able to determine the onset of valgus or varus angulations of the distal tibial fragment in the fracture zone after the tibial intramedullary nail was inserted through the standard entry point. [ABSTRACT FROM AUTHOR]

Ligand‐solvent engineering has been widely applied to improve the quality of perovskite films by forming intermediate films. However, there is an inconsistent understanding in the studies on the composition and mechanism of intermediate films formed by different ligand solvents, and the influence on perovskite film morphology is still elusive. Herein, the pure intermediate films (composed of pure crystal nucleus and amorphous precursor) are fabricated by the addition of ligand solvents with different coordination abilities. Notably, a single heterogeneous nucleation process is induced by the pure intermediate film, resulting in the formation of vertically arranged internal perovskite crystals with few horizontal boundaries, that improve charge transfer and device performance. Furthermore, the small and uniform crystals obtained by adding a ligand solvent with weak coordination ability result in smooth films and a smaller device current (Jsc = 22.74 mA cm−2, PCE = 19.58%). In contrast, the large and uneven crystals obtained by strong coordination ability lead to rough films and a larger device current (Jsc = 23.24 mA cm−2, PCE = 20.72%). This study is devoted to providing a significance reference for the fabrication of perovskite films with vertically arranged internal grains and superior surface textures. [ABSTRACT FROM AUTHOR]

The nucleation and crystallization processes within solution‐processed deposition is key for obtaining perovskite films with high quality. Herein, the synergistic effect of Cs+, ligand solvent (tetramethylene sulfoxide, TMSO), and methylammonium ions (MA+) on nucleation and crystallization procedures of preparing perovskites films is studied. The results reveal that producing α‐phase nuclei in the intermediate‐phase film (a perovskite film formed by removing the solvent before annealing) is the key factor for obtaining α‐phase‐pure perovskites, wherein Cs+ is necessary for reducing the formation energy of the α‐phase. In addition, the nonvolatile ligand (TMSO) is used to inhibit rapid nucleation, because it can form a stable intermediate phase. Furthermore, the introduction of the volatile MA+ cations compound (MACl) combined with Cs+ contributed to the direct formation of α‐phase nuclei in the intermediate‐phase film, and ion exchange (between FA+ and MA+) occurs during the subsequent annealing process, which leads to the formation of large‐grain perovskite film with good crystallinity. Maximum power conversion efficiencies of 22.08% and 16.88% are obtained via this strategy for a perovskite solar cell on a small area (active area: 0.09 cm2) and a perovskite solar module (aperture area: 12.92 cm2), respectively. [ABSTRACT FROM AUTHOR]

The fabrication of large area perovskite solar modules (PSMs) is attracting increasing attention. Traditionally, thin film solar modules are prepared by laser‐engraving several isolated lines to create a series of subcells. This process inevitably leads to an increase in series resistance when combining the subcells. Herein, a facile structure combining series and parallel cell connections is designed and developed for constructing PSMs. A champion power conversion efficiency (PCE) of 18.82% is achieved for perovskite composite modules with a designated area of 21.06 cm2. Furthermore, the PSMs can continue to operate even when parts of the device are shaded or broken. Because of the repeated structural arrangement, these modules may be suitable for fabrication on a broader scale for commercial applications. [ABSTRACT FROM AUTHOR]

As the power conversion efficiency (PCE) of perovskite solar cells (PSCs) is increased to as high over 25%, it becomes pre‐eminent to study a scalable process with wide processing window to fabricate large‐area uniform perovskite films with good light‐trapping performance. A stable and uniform intermediate‐state complex film is obtained by using tetramethylene sulfoxide (TMSO), which extends the annealing window to as long as 20 min, promotes the formation of a high‐quality perovskite film with larger grains (over 400 nm) and spontaneously forms the surface texture to result in an improved fill factor and open‐circuit voltage (Voc). Moreover, the superior surface texture significantly increases the long‐wavelength response, leading to an improved short‐circuit current density (Jsc). As a result, the maximum PCE of 21.14% is achieved based on a simple planar cell structure without any interface passivation. Moreover, a large area module with active area of 6.75 cm2 is assembled using the optimized TMSO process, showing efficiency as high as 16.57%. The study paves the way to the rational design of highly efficient PSCs for potential scaled‐up production. [ABSTRACT FROM AUTHOR]

Perovskite solar cells are sensitive to subtle changes in atmospheric conditions, resulting in problems such as the collapse of the perovskite structure and sharp drops in efficiency. Internal defects are also a big obstacle for high‐quality polycrystalline perovskites. At present, it is difficult to control the density of the trapping sites. By using the bidentate chelating agent thenoyltrifluoroacetone (ttfa), the crystallization kinetics, grain sizes, and crystal defect of Cs‐, methylammonium‐, and formamidinium‐based perovskite materials can be to effectively controlled through a nucleation and growth process for the preparation of perovskite crystals. Crystalline‐state tuning during the crystallization process to obtain better quality perovskite thin films can be achieved with no additional operation, which is suitable for the needs of modern industrial production and management. The chelating agent can effectively passivate the defects in perovskite films, leading to a low defect density and a long charge carrier lifetime. As a result, the ttfa‐passivated perovskite solar cell demonstrated a high power conversion efficiency of 19.70 % with superior stability retention of 64 % of the initial power conversion efficiency after two weeks unencapsulated storage in an adverse atmosphere with approximately 50 % relative humidity. [ABSTRACT FROM AUTHOR]

P-Stereogenic chiral phosphine BI-BOP is employed for the first time as ligand to promote catalytic enantioselective synthesis of phosphoryl-substituted atropisomeric vinylarenes through a palladium−carbene pathway. This strategy utilizes 10 mol% palladium(II) acetate, 10 mol% phosphine ligand as well as a variety of N-tosylhydrazones and phosphoryl-substituted aryl bromides as the reaction partners. The desired axially chiral vinylarenes were isolated with up to 80% yield and 96:4 er, and can be further converted effectively and stereoselectively into dialkylphosphoryl-substituted atropisomeric arenes through a Grignard reaction. This protocol offers a general approach to synthesize phosphoryl-substituted atropisomeric vinylarenes with high enantiomeric purities. [ABSTRACT FROM AUTHOR]

The use of chiral phosphinamides is relatively unexplored because of the lack of a general method for the synthesis. Reported herein is the development of a general, efficient, and highly enantioselective method for the synthesis of structurally diverse P-stereogenic phosphinamides. The method relies on nucleophilic substitution of a chiral phosphinate derived from the versatile chiral phosphinyl transfer agent 1,3,2-benzoxazaphosphinine-2-oxide. These chiral phosphinamides were utilized for the first synthesis of readily tunable P-stereogenic Lewis base organocatalysts, which were used successfully for highly enantioselective catalysis. [ABSTRACT FROM AUTHOR]

The use of chiral phosphinamides is relatively unexplored because of the lack of a general method for the synthesis. Reported herein is the development of a general, efficient, and highly enantioselective method for the synthesis of structurally diverse P-stereogenic phosphinamides. The method relies on nucleophilic substitution of a chiral phosphinate derived from the versatile chiral phosphinyl transfer agent 1,3,2-benzoxazaphosphinine-2-oxide. These chiral phosphinamides were utilized for the first synthesis of readily tunable P-stereogenic Lewis base organocatalysts, which were used successfully for highly enantioselective catalysis. [ABSTRACT FROM AUTHOR]