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Nanopores, due to their advantages of being modifiable, controllability and sensitivity, have made a splash in recent years in the fields of biomolecular sequencing, small molecule detection, salt differential power generation, and biomimetic ion channels. In these applications, the role of chemical or biological modification is indispensable. Compared with small molecules, the modification of polymers is more difficult and the methods are more diverse. Choosing an appropriate modification method directly determines the success or failure of a research project; therefore, it is necessary to summarize polymer modification methods toward nanopores. In addition, it is also important to provide clear and convincing evidence that the nanopore modification is successful, the corresponding characterization methods are also indispensable. Therefore, this review will summarize the methods of polymer modification of nanopores and efficient characterization methods. We hope that this review will provide some reference value for like‐minded researchers. [ABSTRACT FROM AUTHOR]

Osmotic energy represents a promising energy resource because it is sustainable and environmentally benign. Subnanoscale channels are considered as a competitive platform for generating this blue energy due to their highly selective and ultrafast ion transport. However, fabricating functional subnanochannels capable of high energy output remains challenging. Here, a heterogeneous subnanochannel membrane formed by coating a functionalized self‐assembled metal−organic framework (MOF) monolayer (SAMM) film on a porous anodic aluminum oxide membrane, is reported. The SAMM film, with a thickness of ≈160 nm, is fabricated by self‐assembly of poly(methyl methacrylate‐co‐vinylimidazole)‐modified UiO‐66‐NH2 nanoparticles at the water−air interface. In the SAMM, imidazole and NH2 groups provide abundant positive charges, while the angstrom‐scale windows act as ionic filters for selective screening of anions with different hydration diameters. As a result, the heterogeneous membrane exhibits excellent capacity for anion‐selective transport, which contributes to an optimal osmotic power of 6.76 W m−2 under a 100‐fold NaCl gradient, as well as a high Cl−/SO42− selectivity of ≈42.2. Further, the output power is increased to 10.5 W m−2 by methylating imidazole moieties on the MOF surface. This work provides a facile and modular approach to fabricate subnanochannels for enabling highly selective and efficient osmotic energy conversion. [ABSTRACT FROM AUTHOR]

The reduction of ketones or alkenes is an attractive and challenging task in organic chemistry and has widespread applications in the production of fine chemicals, fragrances, pharmaceuticals, vitamins, and functional materials. Classical reduction methods usually require the use of potentially dangerous hydrogen and the reaction under high temperature and pressure conditions, so environmentally friendly, economical, simple, and safe reduction methods are urgently needed. This paper innovatively reports a method for the electrochemical reduction of diarylketones or aryl alkenes in a mixed solvent system of CH3CN/THF. The reaction proceeds smoothly, and the corresponding products are obtained in high yields. The mechanistic study shows that the reaction is a free radical reaction, and reveals the necessity of CH3CN solvent, which plays the three roles of solvent, proton donors, and reactant at the same time. Furthermore, the high yield of the gram‐scale experiment successfully confirmed the potential industrial application of this electrochemical method. [ABSTRACT FROM AUTHOR]

Designing a sustainable security model that carries multilevel information with numerous optical states will significantly enhance anti‐counterfeiting abilities to deter counterfeits, ranging from artworks, currencies, and foods to medicines, but is enormously challenging. Herein, ambient‐friendly, large‐area, quadruple‐level, and chiral luminescent materials are prepared by incorporating lanthanide complexes wrapped in poly(ethylene glycol) matrix into chiral nematic cellulose nanocrystal (CNC) films through a co‐assembly strategy. Due to the regulation of the chiral nematic structures, the composite films enable full‐color structural colors and tunable fluorescence. Notably, the brightest fluorescent film radiates right‐handed circularly polarized luminescence with an asymmetric factor over −0.36, a lifetime up to 510 µs, and an absolute quantum yield up to 66.7%. More interestingly, a fascinating chiro‐optical behavior ranging from azure to khaki can be controlled by a polarizing filter at given 0° and 90° rotation angles. This anti‐counterfeiting system showcases the comprehensive properties of bright and responsive photoluminescence, quadruple and convertible color, and flexible and solvent‐resistant abilities. This CNC‐derived photonic material can act as the multimodal security label on a model banknote, which greatly facilitates its development for practical applications. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Excited‐state hydrogen bond strongly affects the intramolecular charge conversion process, which is very suitable for the design and development of high‐performance fluorescent probes. However, as one of the most common solvents or additives used in sensing, the role of dimethyl sulfoxide (DMSO) in the system of the excited‐state hydrogen bond is seldom explored. As the goal of this research, we investigated the sensing mechanism of a CORM3‐green fluorescent probe system for carbon monoxide releasing molecule (CORM‐3) detection and tracking in vivo, through quantum chemistry calculations based on density‐functional‐theory (DFT)/ time‐dependent density‐functional‐theory (TDDFT) methods. Based on the analysis of the solvent effect of DMSO by the reduced density gradient function and IR spectroscopy, we provided a new strategy to explain the fluorescence mechanism. Subsequently, we verified the result through the potential energy curve of Phthalimide (PTI, the reduced product of CORM3‐green). The excited‐state hydrogen bond between PTI and DMSO promotes radiation transition and leads to obvious difference in the photophysical properties of PTI and PTI‐DMSO. [ABSTRACT FROM AUTHOR]