A Versatile Naphthalimide–Sulfonamide‐Coated Tetraphenylethene: Aggregation‐Induced Emission Behavior,Mechanochromism, and Tracking Glutathione in Living Cells

A tetraphenylethene (TPE) derivative substituted with a sulfonyl‐based naphthalimide unit ( TPE‐Np ) was designed and synthesized. Its optical properties in solution and in the solid state were investigated. Photophysical properties indicated that the target molecule, TPE‐Np , possessed aggregation‐induced emission (AIE) behavior, although the linkage between TPE and the naphthalimide unit was nonconjugated. Additionally, it exhibited an unexpected, highly reversible mechanochromism in the solid state, which was attributed to the change in manner of aggregation between crystalline and amorphous states. On the other hand, a solution of TPE‐Np in a mixture of dimethyl sulfoxide/phosphate‐buffered saline was capable of efficiently distinguishing glutathione (GSH) from cysteine and homocysteine in the presence of cetyltrimethylammonium bromide. Furthermore, the strategy of using poly(ethylene glycol)–polyethylenimine (PEG‐PEI) nanogel as a carrier to cross‐link TPE‐Np to obtain a water‐soluble PEG‐PEI/ TPE‐Np nanoprobe greatly improved the biocompatibility, and this nanoprobe could be successfully applied in the visualization of GSH levels in living cells.     

An All‐Inorganic Perovskite‐Phase Rubidium Lead Bromide Nanolaser

Rubidium lead halides (RbPbX₃), an important class of all‐inorganic metal halide perovskites, are attracting increasing attention for photovoltaic applications. However, limited by its lower Goldschmidt tolerance factor t≈0.78, all‐inorganic RbPbBr₃ has not been reported. Now, the crystal structure, X‐ray diffraction (XRD) pattern, and band structure of perovskite‐phase RbPbBr₃ has now been investigated. Perovskite‐phase RbPbBr₃ is unstable at room temperature and transforms to photoluminescence (PL)‐inactive non‐perovskite. The structural evolution and mechanism of the perovskite–non‐perovskite phase transition were clarified in RbPbBr₃. Experimentally, perovskite‐phase RbPbBr₃ was realized through a dual‐source chemical vapor deposition and annealing process. These perovskite‐phase microspheres showed strong PL emission at about 464 nm. This new perovskite can serve as a gain medium and microcavity to achieve broadband (475–540 nm) single‐mode lasing with a high Q of about 2100.     

Hole‐Boosted Cu(Cr,M)O2 Nanocrystals for All‐Inorganic CsPbBr3 Perovskite Solar Cells

The all‐inorganic CsPbBr₃ perovskite solar cell (PSC) is a promising solution to balance the high efficiency and poor stability of state‐of‐the‐art organic–inorganic PSCs. Setting inorganic hole‐transporting layers at the perovskite/electrode interface decreases charge carrier recombination without sacrificing superiority in air. Now, M‐substituted, p‐type inorganic Cu(Cr,M)O₂ (M=Ba²⁺, Ca²⁺, or Ni²⁺) nanocrystals with enhanced hole‐transporting characteristics by increasing interstitial oxygen effectively extract holes from perovskite. The all‐inorganic CsPbBr₃ PSC with a device structure of FTO/c‐TiO₂/m‐TiO₂/CsPbBr₃/Cu(Cr,M)O₂/carbon achieves an efficiency up to 10.18 % and it increases to 10.79 % by doping Sm³⁺ ions into perovskite halide, which is much higher than 7.39 % for the hole‐free device. The unencapsulated Cu(Cr,Ba)O₂‐based PSC presents a remarkable stability in air in either 80 % humidity over 60 days or 80 °C conditions over 40 days or light illumination for 7 days.     

Insight into Three‐Coordinate Aluminum Species on Ethanol‐to‐Olefin Conversion over ZSM‐5 Zeolites

Commercial bioethanol can be readily converted into ethylene by a dehydration process using solid acids, such as Brønsted acidic H‐ZSM‐5 zeolites, and thus, it is an ideal candidate to replace petroleum and coal for the sustainable production of ethylene. Now, strong Lewis acidic extra‐framework three‐coordinate Al³⁺ species were introduced into H‐ZSM‐5 zeolites to improve their catalytic activity. Remarkably, Al³⁺ species working with Brønsted acid sites can accelerate ethanol dehydration at a much lower reaction temperature and shorten the unsteady‐state period within 1–2 h, compared to >9 h for those without Al³⁺ species, which can significantly enhance the ethanol dehydration efficiency and reduce the cost. The reaction mechanism, studied by solid‐state NMR, shows that strong Lewis acidic EFAl‐Al³⁺ species can collaborate with Brønsted acid sites and promote ethanol dehydration either directly or indirectly via an aromatics‐based cycle to produce ethylene.     

A New Perspective on Borane Chemistry: The Nucleophilicity of the B−H Bonding Pair Electrons

A number of recently discovered nucleophilic boron compounds, such as boryl anions and borylenes, are breaking the rules regarding boron and boron‐containing compounds and their reputation as Lewis acids/electrophiles. In a similar fashion, the B?H bonding pair electrons in boranes also show nucleophilicity which is ascribed to the lower electronegativity of boron relative to that of hydrogen. However, this nucleophilicity of the B?H bond has received far less attention. Explorations of the nucleophilicity of the B?H bonding pair electrons have led to the formation of B?H?B bonded units and B?H???H?Y dihydrogen bonds, based on which new chemistry has been uncovered, including the elucidation of the mechanism of formation of aminodiborane (ADB), the diammoniate of diborane (DADB), and lithium or sodium salts of octahydrotriborates (B₃H₈^?), as well as the development of more convenient and straightforward synthetic routes to these reagents. Moreover, the recognition of the nucleophilic properties of the B?H bonding pair electrons will also help to more deeply understand the different mechanisms operating in hydroboration reactions.     

Bio‐inspired Design and Additive Manufacturing of Soft Materials,Machines, Robots,and Haptic Interfaces

Soft materials possess several distinctive characteristics, such as controllable deformation, infinite degrees of freedom, and self‐assembly, which make them promising candidates for building soft machines, robots, and haptic interfaces. In this Review, we give an overview of recent advances in these areas, with an emphasis on two specific topics: bio‐inspired design and additive manufacturing. Biology is an abundant source of inspiration for functional materials and systems that mimic the function or mechanism of biological tissues, agents, and behaviors. Additive manufacturing has enabled the fabrication of materials and structures prevalent in biology, thereby leading to more‐capable soft robots and machines. We believe that bio‐inspired design and additive manufacturing have been, and will continue to be, important tools for the design of soft robots.     

Eutectic Molecular Liquids Based on Hydrogen Bonding and π–π Interaction for Exfoliating Two‐dimensional Materials and Recycling Polymers

Eutectic molecular liquids (EMLs) based on hydrogen‐bonding interaction and π–π stacking were prepared. We found that the thermodynamic properties like initial decomposition temperature and glass transition temperature of EMLs are mainly dominated by the hydrogen bond donor, which is beneficial for designing and preparing new EMLs. These new liquid systems could be applied in the field of environmental and material science.