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Perovskite light‐emitting diodes (PeLEDs) that can be air‐processed promises the development of displaying optoelectronic device, while is challenged by technical difficulty on both the active layer and hole transport layer (HTL) caused by the unavoidable humidity interference. Here, we propose and validate that, planting the polymer brush with tailored functional groups in inorganic HTL, provides unique bilateral embedded anchoring that is capable of simultaneously addressing the n phases crystallization rates in the active layer as well as the deteriorated particulate surface defects in HTL. Exemplified by zwitterionic polyethyleneimine‐sulfonate (PEIS) in present study, its implanting in NiOx HTL offers abundant nuclei sites of amino and sulfonate groups that balance the growth rate of different n phases in quasi‐2D perovskite films. Moreover, the PEIS effectively nailed the interfacial contact between perovskite and NiOx, and reduced the particulate surface defects in HTL, leading to the enhanced PLQY and stability of large‐area blue perovskite film in ambient air. By virtue of these merits, present work achieves the first demonstration of the air‐processed blue PeLEDs in large emitting area of 1.0 cm2 with peak external quantum efficiency (EQE) of 2.09 %, which is comparable to the similar pure‐bromide blue PeLEDs fabricated in glovebox. [ABSTRACT FROM AUTHOR]

ABSTRACT Encouraged by the emerging infrared thermography (IT)–based technique for determining fatigue limit of composite materials, this study introduces a novel approach for the quick fatigue limit determination based on acoustic emission (AE) technology. The AE‐based method expands fatigue testing capabilities beyond the IT‐based methods. Fatigue experiments were conducted for the composite laminates and composite sandwich panels subjected to stepwise increasing cyclic loads. For composite laminate specimens subjected to tension–tension and tension–compression fatigue loads, the fatigue limits obtained by the AE‐based method are in good correlation with those acquired from the IT‐based method as well as the conventional up‐and‐down test procedure. In the tests for out‐of‐plane shearing fatigue limits of composite sandwich panel specimens, where the IT‐based method did not work properly, the AE‐based method performed well and obtained the fatigue limit estimation, which is in line with that derived from the S–N curve data, thereby demonstrating its high adaptability. [ABSTRACT FROM AUTHOR]

The deep‐blue perovskite light‐emitting diodes (PeLEDs) are of essential and indispensable for the application in full‐gamut display. However, the deep blue emission required large bandgap in small n phase exhibits high surface activity that gives rise to the difficulty of n phase distribution control spatially and proportionally in quasi‐2D perovskite films. Here, the deep‐blue pure‐bromide perovskite films is present that exhibit spatially vertical n phase distribution, owing to the partially ionized amino acid salt of 3‐Ammonium propionic acid bromide (3CBr) modulated crystallization kinetic of perovskite. The strong interaction of 3CBr and perovskite lattice improves the stability of small n phases, showing tunable photoluminescence (PL) emission and enhanced PL quantum yield (PLQY). The achieved champion deep blue PeLED shows a maximum EQE of 3.64% at electroluminescence (EL) emission wavelength of 466 nm, locating at the top rank of the similar devices. This work provides an effective strategy to fabricating efficient deep‐blue perovskite films and devices, promoting the development of perovskite‐based application in display. [ABSTRACT FROM AUTHOR]

Formamide (HCONH2) plays a pivotal role in the manufacture of a diverse array of chemicals, fertilizers, and pharmaceuticals. Photocatalysis holds great promise for green fabrication of carbon‐nitrogen (C−N) compounds owing to its environmental friendliness and mild redox capability. However, the selective formation of the C−N bond presents a significant challenge in the photocatalytic synthesis of C−N compounds. This work developed a photocatalytic radical coupling method for the formamide synthesis from co‐oxidation of ammonia (NH3) and methanol (CH3OH). An exceptional formamide yield rate of 5.47±0.03 mmol ⋅ gcat−1 ⋅ h−1 (911.87±5 mmol ⋅ gBi−1 ⋅ h−1) was achieved over atomically dispersed Bi sites (BiSAs) on TiO2. An accumulation of 45.68 mmol ⋅ gcat−1 (2.0 g ⋅ gcat−1) of formamide was achieved after long‐term illumination, representing the highest level of photocatalytic C−N compounds synthesis. The critical C−N coupling for formamide formation originated from the "σ–σ" interaction between electrophilic ⋅CH2OH with nucleophilic ⋅NH2 radical. The BiSAs sites facilitated the electron transfer between reactants and photocatalysts and enhanced the nucleophilic attack of ⋅NH2 radical on the ⋅CH2OH radical, thereby advancing the selective C−N bond formation. This work deepens the understanding of the C−N coupling mechanism and offers an intriguing photocatalytic approach for the efficient and sustainable production of C−N compounds. [ABSTRACT FROM AUTHOR]