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The pursuit of fabricating high‐performance graphene films has aroused considerable attention due to their potential for practical applications. However, developing both stretchable and tough graphene films remains a formidable challenge. To address this issue, we herein introduce mechanical bond to comprehensively improve the mechanical properties of graphene films, utilizing [2]rotaxane as the bridging unit. Under external force, the [2]rotaxane cross‐link undergoes intramolecular motion, releasing hidden chain and increasing the interlayer slip distance between graphene nanosheets. Compared with graphene films without [2]rotaxane cross‐linking, the presence of mechanical bond not only boosted the strength of graphene films (247.3 vs 74.8 MPa) but also markedly promoted the tensile strain (23.6 vs 10.2 %) and toughness (23.9 vs 4.0 MJ/m3). Notably, the achieved tensile strain sets a record high and the toughness surpasses most reported results, rendering the graphene films suitable for applications as flexible electrodes. Even when the films were stretched within a 20 % strain and repeatedly bent vertically, the light‐emitting diodes maintained an on‐state with little changes in brightness. Additionally, the film electrodes effectively actuated mechanical joints, enabling uninterrupted grasping movements. Therefore, the study holds promise for expanding the application of graphene films and simultaneously inspiring the development of other high‐performance two‐dimensional films. [ABSTRACT FROM AUTHOR]

The family of MAX phases and their two‐dimensional derivative MXenes attract significant attention due to their unparalleled properties. Synthesis of MAX phases and MXene from biomass sources is important to expand their biology‐related applications, while it remains a challenge. The present work explores the possibility to synthesize MAX phases and subsequently derive MXenes by using biomass precursor. Ti3AlC2 MAX phase was synthesized by using glucose as the carbon source in molten salt. The conversion behavior from glucose to Ti3AlC2 was investigated, and the conversion rate of carbon from glucose reached to 70.4% by optimizing the reaction conditions. The as‐obtained Ti3AlC2 can be derived into Ti3C2Tx MXene and MXene quantum dots by common chemical treatments, which provides possibility for biomass‐derived nanolaminates applying in biological applications such as biological catalysis, bioinstrumentation, and biological tracking. [ABSTRACT FROM AUTHOR]

Facing the future development trend of miniaturization and intelligence of electronic devices, solar‐blind photodetectors based on ultrawide‐bandgap 2D semiconductors have the advantages of low dark current, and high signal‐to‐noise ratio, as well as the features of micro‐nanometer miniaturization and multi‐functionalization of 2D material devices, which have potential applications in the photoelectric sensor part of high‐performance machine vision systems. This study reports a 2D oxide semiconductor, AsSbO3, with an ultrawide bandgap (4.997 eV for monolayer and 4.4 eV for multilayer) to be used to fabricate highly selective solar‐blind UV photodetectors, of which the dark current as low as 100 fA and rejection ratio of UV‐C and UV‐A reaches 7.6 × 103. Under 239 nm incident light, the responsivity is 105 mA W−1 and the detectivity is 7.58 × 1012 Jones. Owing to the remarkable anisotropic crystal structure, AsSbO3 also shows significant linear dichroism and nonlinear optical properties. Finally, a simple machine vision system is simulated by combining the real‐time imaging function in solar‐blind UV with a convolutional neural network. This study enriches the material system of ultrawide‐bandgap 2D semiconductors and provides insight into the future development of high‐performance solar‐blind UV optoelectronic devices. [ABSTRACT FROM AUTHOR]

In recent years, valleytronics researches based on 2D semiconducting transition metal dichalcogenides have attracted considerable attention. On the one hand, strong spin–orbit interaction allows the presence of spin–valley coupling in this system, which provides spin addressable valley degrees of freedom for information storage and processing. On the other hand, large exciton binding energy up to hundreds of meV enables excitons to be stable carriers of valley information. Valley polarization, marked by an imbalanced exciton population in two inequivalent valleys (+ K and − K), is the core of valleytronics as it can be utilized to store binary information. Motivated by the potential applications, we present a thorough overview of the recent advancements in the generation, relaxation, manipulation, and transport of the valley polarization in nonmagnetic transition metal dichalcogenide layered semiconductors. We also discuss the development of valleytronic devices and future challenges in this field. [ABSTRACT FROM AUTHOR]

Basophils are crucial in regulating allergic reactions via immediate secretion of multiple mediators upon IgE‐induced degranulation. IL‐3 regulates the development and activation of human basophils while epithelial cytokine thymic stromal lymphopoietin (TSLP) is another key regulator for murine basophils. Despite association of increased TSLP with exaggerated basophil responses in oesophageal biopsies, the effects of TSLP in regulating human basophil degranulation and activation are under debate. In this study, we aimed to examine whether human basophils responded to TSLP by co‐expression of TSLP receptors, TSLPR and IL‐7Rα (CD127), upon in vitro activation and in sputum of allergic asthmatic patients. Flow cytometric analysis of fresh basophils from healthy controls revealed no detectable TSLPR and CD127. Further flow cytometric analysis of basophils from healthy controls in vitro stimulated by multiple established basophil modulators for 24 hours showed induction of TSLPR but not CD127 by IL‐3 (10 ng/ml), anti‐IgE (10 μg/ml) and C5a (50 ng/ml). One‐hour stimulation of basophils from allergic asthmatic patients and healthy controls by TSLP (50 ng/ml) with or without IL‐3 (10 ng/ml) and anti‐IgE (10 μg/ml) had no effect on induction of CD63+ degranulated basophils. Similarly, TSLP (50 ng/ml) with or without IL‐3 (10 ng/ml) and anti‐IgE (10 μg/ml) did not induce IL‐4 and IL‐13 production by basophils from healthy controls. Further ex vivo analysis revealed that sputum basophils from allergic asthmatic patients did not express CD127. We conclude that human basophils from healthy controls and allergic asthmatic patients do not respond to TSLP as lacking CD127. [ABSTRACT FROM AUTHOR]