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Excess PbI2 has been deemed as indispensable component to boost the efficiency of perovskite solar cells (PSCs). However, the random aggregation of PbI2 crystals seriously disturbs the transport behavior of the carrier and accelerates the degradation of perovskite film. Herein, an effective strategy to in situ disperse excess PbI2 crystals via the columnar liquid crystal (T6TE) is developed. Rapid self‐assembly induced by intermolecular π–π interaction enables T6TE to form the ordered columnar phase with "edge‐on" orientation in perovskite. The columnar T6TE can efficiently disperse excess PbI2 crystals with the merits of strong negative electrostatic potential and highly steric hindrance. Target perovskite deserves preferable crystallization and reconstructed surface, leading to reduced defects density, less residual stress, and efficient carrier transport. Besides, the T6TE significantly impedes the degradation of perovskite film and the formation of Pb0 defects. Resultant T6TE‐assisted PSCs achieve the champion power conversion efficiency (PCE) of 24.27% for mixed Cs+‐FA+‐MA+ perovskite. The PCE of a larger area (1 cm2) device reaches to 21.50%. The unencapsulated device maintains ≈85% of the initial PCE after 1500 h storage in the atmosphere with 40–60% relative humidity. This work provides a new strategy to in situ disperse excess PbI2 by incorporating columnar liquid crystal for the first time. [ABSTRACT FROM AUTHOR]

Perovskite Solar Cells In article number 2303166, Hongli Liu and co‐workers developed a columnar liquid crystal, in situ dispersing the excess PbI2 component in perovskite. Target perovskite gains optimal crystallization, released residual stress, and less defects with no aggregated PbI2 crystals, leading to efficient carrier transfer. The optimized perovskite solar cells achieve a power conversion efficiency of 24.27% with preferable stability. [ABSTRACT FROM AUTHOR]

Hybridized local and charge‐transfer (HLCT) with the utilization of both singlet and triplet excitons through the “hot excitons” channel have great application potential in highly efficient blue organic light‐emitting diodes (OLEDs). The proportion of charge‐transfer (CT) and locally excited (LE) components in the relevant singlet and triplet states makes a big difference for the high‐lying reverse intersystem crossing process. Herein, three novel donor (D)‐acceptor (A) type HLCT materials, 7‐([1,1′‐biphenyl]‐4‐yl(9,9‐dimethyl‐9H‐fluoren‐2‐yl)amino)‐3‐phenyl‐1H‐isochromen‐1‐one (pPh‐7P), 7‐([1,1′‐biphenyl]‐4‐yl(9,9‐dimethyl‐9H‐fluoren‐2‐yl)amino)‐3‐methyl‐1H‐isochromen‐1‐one (pPh‐7M), and 6‐([1,1′‐biphenyl]‐4‐yl(9,9‐dimethyl‐9H‐fluoren‐2‐yl)amino)‐3‐methyl‐1H‐isochromen‐1‐one (pPh‐6M), were rationally designed and synthesized with diphenylamine derivative as donor and oxygen heterocyclic coumarin moiety as acceptors. The proportions of CT and LE components were fine controlled by changing the connection site of diphenylamine derivative at C6/C7‐position and the substituent at C3‐position of coumarin moiety. The HLCT characteristics of pPh‐7P, pPh‐7M, and pPh‐6M were systematically demonstrated through photophysical properties and density functional theory calculations. The solution‐processed doped OLEDs based on pPh‐6M exhibited deep‐blue electroluminescence with the maximum emission wavelength of 446 nm, maximum luminance of 8755 cd m−2, maximum current efficiency of 5.83 cd A−1, and maximum external quantum efficiency of 6.54 %. The results reveal that pPh‐6M with dominant 1LE and 3CT components has better OLED performance. [ABSTRACT FROM AUTHOR]

Background: Studies have suggested that acute myeloid leukemia (AML) patients with incomplete hematologic recovery undergoing allogeneic stem cell transplantation (allo‐HSCT) had inferior overall survival (OS). Study Design and Methods: This single‐center, retrospective study of AML patients evaluated the relationship between red blood cell (RBC) and platelet (PLT) transfusion requirements during the first 30 days and long‐term outcomes after allo‐HSCT through multivariate analyses. Results: A total of 692 AML patients received peripheral blood stem cells (89.2%), marrow (5.6%), or umbilical cord (5.2%) from matched related (37.4%), unrelated (49.1%), or haploidentical (8.2%) donors in 2011–2017. Transfusion requirements during the first 30 days for RBC (89.5% transfused, median 3, range 1–18 units) or PLT (98.2% transfused, median 6, range 1–144 units) were variable. By Day 30, 56.7% (95% confidence interval [CI]: 52.8–60.3%) and 86.1% (95% CI: 83.2–88.5%) had achieved RBC and PLT transfusion independence, respectively. Median follow‐up among survivors (n = 307) was 7.1 years (range: 2.7–11.8). Lack of RBC transfusion independence by Day 30 was strongly and independently associated with worse 5‐year OS (39.2% vs. 59.6%, adjusted hazard ratio [HR] 1.83, 95% CI: 1.49–2.25), leukemia‐free survival (35.8% vs. 55.5%, HR = 1.75, 95% CI: 1.43–2.14), and NRM (29.7% vs. 13.7%, HR = 2.05, 95% CI: 1.45–2.89) (p <.001). There was no difference in relapse rates among patients who achieved or did not achieve RBC (p =.34) or PLT (p =.64) transfusion independence. Conclusion: Prolonged RBC dependence predicted worse survival and NRM rates, but not increased relapse. Posttransplant surveillance of such patients should be adjusted with more attention to non‐relapse complications. [ABSTRACT FROM AUTHOR]

Carbon nanotube reinforced natural rubber composites (CNT/NRs) have been increasingly used in industry. However, due to the large aspect ratio and high curling of CNTs, the traditional theoretical models that have been used for inclusion-reinforced composites cannot be applied to CNT/NRs directly. Therefore, a longer time is needed to predict the elastic properties of CNT/NRs in experiments. In this work, the classical macroscopic model and mesoscopic method were used to predict the elastic performance of CNT/NRs prepared by the latex blending method. Three types of phenomenological models were employed: Mooney–Rivlin, Ogden, and Yeoh. A comparison with the experimental results shows that the Ogden model describes the constitutive behavior of CNT/NRs more accurately. In addition, at the mesoscale, the Halpin–Tsai equation, Mori–Tanaka model, and finite element method were employed to predict the elastic modulus based on the persistent length theory. The stress-strain curves under large deformations were compared with those of the experimental results. Therefore, the applicability of the three mesoscale models were verified for the CNT/NRs studied in this work. [ABSTRACT FROM AUTHOR]

[Display omitted] • This material is capable of withstanding highly acidic (3–8 M HNO 3), highly radioactive (∼200 kGy), and highly heated (∼200 °C) conditions. • It has good stability, being able to withstand prolonged exposure to high acid without any impact on its efficacy. • The material has great selectivity, and even when there are hundreds or thousands of times more interfering ions, it still has a particular selectivity to Eu(III). • This material is cost-effective, its synthesis is uncomplicated, the raw materials are readily available, and it can be reused - these are all advantages. Americium (Am), a radioactive element, is highly valued for its commercial uses. Its source is primarily derived from high-acid, high-radiation, and high-temperature high-level radioactive waste liquids, requiring materials that are capable of enduring the most intense conditions for its capture. For this challenging environment, we successfully created a composite material TODGA@SiO 2 that is capable of effectively separating Am3+. An exhaustive evaluation of the material was undertaken, focusing on essential parameters and the column behavior of the material to ascertain its suitability for engineering applications. The composite is highly resistant to acid (>3 M HNO 3), can withstand temperatures up to 200 °C, and is radiation resistant up to 200 kGy, making it a great choice. Highlighting its suitability for radioactive waste, the adsorbent exhibited outstanding stability even after being soaked in 3 M HNO 3 for 11 days. In terms of performance, this material had a rapid kinetics (1 min, >95 %), a considerable adsorption capacity (K d value close to 3 × 105 mL/g), and a high selectivity for Am3+. From a cost and environmental protection perspective, the adsorbent can be regenerated and reused at least five times, and the extractant structure adheres to the CHON (Carbon, Hydrogen, Oxygen, and Nitrogen) principle, so orderly disposal is simple. At the same time, the high column efficiency, with a recovery rate of Am3+ of more than 94 %, makes its industrial application highly practical. In comparison to existing adsorbents, the material reported in this work has shown greater efficacy, making it a suitable inorganic composite for Am3+ extraction from radioactive liquid waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • The strategy of FAECDIP simultaneously realizes mixed-halide and doping for efficient deep-blue PQDs. • Ca2+ passivates the defects and enhances the exciton binding energy of PQDs to favor structural stability and carrier transportation. • The Ca2+-introduced deep blue PeLED enables a record EQE of 5.88 % (447 nm) with a CIE of (0.158, 0.018) up to date. Despite the impressive development of perovskite light-emitting diodes (PeLEDs), it is still challenging to achieve high-efficiency deep-blue PeLEDs using colloid perovskite quantum dots (PQDs). The efficiency of PQDs with a wavelength below 460 nm, which meets the requirements for deep-blue emission in the Telecommunication Union UHD television standard (ITU REC. 2020), lags far behind those of their sky-blue counterparts. To address this issue, a novel strategy of fast anion-exchange & cation-doping inter-promotion (FAECDIP) is proposed to achieve highly efficient deep-blue PQDs by introducing CaBr 2 into the CsPbCl 3 PQDs. Owing to the presence of Ca2+, the speed of ion exchange is increased, driven by the smaller cation, Ca2+, improving the preparation efficiency. Additionally, Ca2+ was doped on the surface of PQDs. Based on studies of fast anion-exchange and theoretical calculations, Ca2+ improves the optical performance by decreasing the number of traps and increasing the crystallinity of target PQDs, facilitating the stability of treated films and PeLEDs by enhancing the formation energy of halogen vacancies. Here, a high PLQY of 80.3 % CaBr 2 -induced CsPb(Cl/Br) 3 deep-blue PQDs (∼446 nm) was achieved. The correspondent PeLEDs (∼447 nm) achieved a superior EQE of 5.88 %, which is the state-of-the-art among the reported deep-blue PeLEDs. Our strategy provides a potential route to achieve deep-blue PeLEDs, which differs from the previous tedious-complex methods. [ABSTRACT FROM AUTHOR]