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Metal‐organic frameworks (MOFs) have drawn growing attention as promising electrode candidates for rechargeable batteries. However, most studies focus on the direct use of MOF electrodes without any modification. Post‐synthetic modification, a judicious tool to modify targeted properties of MOFs, has been long‐neglected in the field of batteries. Herein, crystal‐facet engineering is proposed to design MOF‐based electrodes with high capacity and fast electrochemical kinetics. We found that a thermally‐modified strategy can regulate the dominant exposed facet of Ni‐based MOF (PFC‐8). With the optimally exposed facets, the battery exhibited admirable rate capability (139.4 mAh g−1 at 2.5 A g−1 and 110.0 mAh g−1 at 30 A g−1) and long‐term stability. Furthermore, density functional theory calculations demonstrate that stronger OH− adsorption behaviors and optimized electronic structures induced by the regulated exposed facets boost the electrochemical performance. [ABSTRACT FROM AUTHOR]

Protocells containing enzyme‐driven biomolecular circuits that can process and exchange information offer a promising approach for mimicking cellular features and developing molecular information platforms. Here, we employ synthetic transcriptional circuits together with CRISPR/Cas‐based DNA processing inside semipermeable protein‐polymer microcompartments. We first establish a transcriptional protocell that can be activated by external DNA strands and produce functional RNA aptamers. Subsequently, we engineer a transcriptional module to generate RNA strands functioning as diffusive signals that can be sensed by neighboring protocells and trigger the activation of internalized DNA probes or localization of Cas nucleases. Our results highlight the opportunities to combine CRISPR/Cas machinery and DNA nanotechnology for protocellular communication and provide a step towards the development of protocells capable of distributed molecular information processing. [ABSTRACT FROM AUTHOR]

Blood–brain barrier (BBB)‐crossing ability of drugs is of paramount importance for the treatments of central nervous system diseases. However, the known methods for drug transport across the BBB are generally complicated and inefficient, and exhibit serious side effects in some cases. Herein, we report an exciting finding that fluorination and betaine modification can significantly augment the BBB‐crossing ability of cylindrical polymer brushes (CPBs), which was demonstrated by the comparison with the CPBs modified with alkyl and poly(ethylene glycol) chains, respectively. We surmise that fluorination enhances the BBB penetration of the CPBs by increasing the hydrophobicity and reducing the surface energy, and betaine medication achieves this function via a betaine transporter BGT1 expressed on brain capillaries. By means of an in vitro BBB model, we demonstrated that the CPBs penetrated the BBB through transendothelial transport. This work provides a novel strategy for enhancing the BBB‐crossing ability of nanomaterials. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) heterostructures with domain‐controlled emissive colors have shown great potential for achieving high‐throughput sensing, anti‐counterfeit and information security. Here, a strategy based on steric‐hindrance effect is proposed to construct lateral lanthanide‐MOFs (Ln‐MOFs) epitaxial heterostructures, where the channel‐directed guest molecules are introduced to rebalance in‐plane and out‐of‐plane growth rates of the Ln‐MOFs microrods and eventually generate lateral MOF epitaxial heterostructures with controllable aspect ratios. A library of lateral Ln‐MOFs heterostructures are acquired through a stepwise epitaxial growth procedure, from which rational modulation of each domain with specific lanthanide doping species allows for definition of photonic barcodes in a two‐dimensional (2D) domain with remarkably enlarged encoding capacity. The results provide molecular‐level insight into the use of modulators in governing crystallite morphology for spatially assembling multifunctional heterostructures. [ABSTRACT FROM AUTHOR]

Unravelling how the complexity of living systems can (have) emerge(d) from simple chemical reactions is one of the grand challenges in contemporary science. Evolving systems of self‐replicating molecules may hold the key to this question. Here we show that, when a system of replicators is subjected to a regime where replication competes with replicator destruction, simple and fast replicators can give way to more complex and slower ones. The structurally more complex replicator was found to be functionally more proficient in the catalysis of a model reaction. These results show that chemical fueling can maintain systems of replicators out of equilibrium, populating more complex replicators that are otherwise not readily accessible. Such complexification represents an important requirement for achieving open‐ended evolution as it should allow improved and ultimately also new functions to emerge. [ABSTRACT FROM AUTHOR]

Whispering‐gallery‐mode (WGM) microcavities featuring distinguishable sharp peaks in a broadband exhibit enormous advantages in the field of miniaturized photonic barcodes. However, such kind of barcodes developed hitherto are primarily based on microcavities wherein multiple gain medias were blended into a single matrix, thus resulting in the limited and indistinguishable coding elements. Here, a surface tension assisted heterogeneous assembly strategy is proposed to construct the spatially resolved WGM hetero‐microrings with multiple spatial colors along its circular direction. Through precisely regulating the charge‐transfer (CT) strength, full‐color microrings covering the entire visible range were effectively acquired, which exhibit a series of sharp and recognizable peaks and allow for the effective construction of high‐quality photonic barcodes. Notably, the spatially resolved WGM hetero‐microrings with multiple coding elements were finally acquired through heterogeneous nucleation and growth controlled by the directional diffusion between the hetero‐emulsion droplets, thus remarkably promoting the security strength and coding capacity of the barcodes. The results would be useful to fabricate new types of organic hierarchical hybrid WGM heterostructures for optical information recording and security labels. [ABSTRACT FROM AUTHOR]

Keywords: 2D photonic barcodes; anti-counterfeiting applications; dimensional modulation; lanthanides; MOF heterostructures EN 2D photonic barcodes anti-counterfeiting applications dimensional modulation lanthanides MOF heterostructures 24931 24931 1 11/02/21 20211108 NES 211108 B Mehrfarbige Heterostrukturen b auf der Basis von Lanthanoid-basierten metallorganischen Gerüsten (Ln-MOFs) haben großes Potenzial für fälschungssichere Anwendungen gezeigt. Innenrücktitelbild: Laterally Engineering Lanthanide-MOFs Epitaxial Heterostructures for Spatially Resolved Planar 2D Photonic Barcoding (Angew. In ihrem Forschungsartikel auf S. 24724 präsentieren Zhenhua Gao, Xiangeng Meng, Yong Sheng Zhao et al. eine Strategie, um laterale 2D-Ln-MOFs zu konstruieren. [Extracted from the article]

X‐ray scintillators have gained significant attention in medical diagnostics and industrial applications. Despite their widespread utility, scintillator development faces a significant hurdle when exposed to elevated temperatures, as it usually results in reduced scintillation efficiency and diminished luminescence output. Here we report a molecular design strategy based on a hybrid perovskite (TpyBiCl5) that overcomes thermal quenching through multi‐excited state switching. The structure of perovskite provides a platform to modulate the luminescence centers. The rigid framework constructed by this perovskite structure stabilized its triplet states, resulting in TpyBiCl5 exhibiting an approximately 12 times higher (45 % vs. 3.8 %) photoluminescence quantum yield of room temperature phosphorescence than that of its organic ligand (Tpy). Most importantly, the interactions between the components of this perovskite enable the mixing of different excited states, which has been revealed by experimental and theoretical investigations. The TpyBiCl5 scintillator exhibits a detection limit of 38.92 nGy s−1 at 213 K and a detection limit of 196.31 nGy s−1 at 353 K through scintillation mode switching between thermally activated delayed fluorescence and phosphorescence. This work opens up the possibility of solving the thermal quenching in X‐ray scintillators by tuning different excited states. [ABSTRACT FROM AUTHOR]

In their Research Article (e202310263), Zhenhua Gao, Yong Sheng Zhao et al. have developed a surface tension assisted heterogeneous assembly strategy to construct WGM hetero-microrings through regulating the charge-transfer (CT) interactions along circular boundaries, which remarkably promotes the security level and encoding capacity of the barcodes. Keywords: Anti-Counterfeiting Applications; Heterogeneous Assembly; Organic Hetero-Microring; Photonic Barcodes; Whispering-Gallery-Mode EN Anti-Counterfeiting Applications Heterogeneous Assembly Organic Hetero-Microring Photonic Barcodes Whispering-Gallery-Mode 1 1 1 11/09/23 20231113 NES 231113 B Whispering-gallery-mode b (WGM) microcavities featuring distinguishable sharp peaks in a broadband exhibit enormous advantages in the field of miniaturized photonic barcodes. Anti-Counterfeiting Applications, Heterogeneous Assembly, Organic Hetero-Microring, Photonic Barcodes, Whispering-Gallery-Mode. [Extracted from the article]

The Catellani reaction has received substantial attention because it enables rapid multiple derivatization on aromatics. While using alkyl electrophiles to achieve ortho‐alkylation was one of the earliest applications of the Catellani reaction, ipso‐alkylation‐terminated reactions with β‐H‐containing reactants has not been realized to date. Herein, we report alkylation‐terminated Catellani reaction using alkyl carbagermatranes (abbreviated as alkyl‐Ge) as nucleophiles. The reactivity of alkyl‐Ge and alkyl‐B(OH)2 in this reaction is discussed. This approach enables efficient dialkylation with β‐H‐containing reactants, which was previously inaccessible by Catellani reactions. [ABSTRACT FROM AUTHOR]

Electrolyte environments, including cations, anions, and solvents are critical for the performance delivery of cathodes of batteries. Most works focused on interactions between cations and cathode materials, in contrast, there is a lack of in‐depth research on the correlation between anions and cathodes. Here, we systematically investigated how anions manipulate the coulombic efficiency (CE) of cathodes of zinc batteries. We take intercalation‐type V2O5 and conversion‐type I2 cathodes as typical cases for profound studies. It was found that electronic properties of anions, including charge density and its distribution, can tune conversion or intercalation reactions, leading to significant CE differences. Using operando visual Raman microscopy and theoretical simulations, we confirm that competitive coordination between anions and I− can regulate CEs by modulating polyiodide diffusion rates in Zn−I2 cells. In Zn−V2O5 cells, anion‐tuned solvation structures vastly affect CEs through varying Zn2+ intercalation kinetics. Conversion I2 cathode achieves a 99 % CE with highly electron‐donating anions, while anions with preferable charge structures that interact strongly with Zn2+ afford an intercalation V2O5 a nearly 100 % CE. Understanding the mechanism of anion‐governed CEs will help us evaluate compatibility of electrolytes with electrodes, thus providing a guideline for anion selection and electrolyte design for high‐energy, long‐cycling zinc batteries. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed enantioselective addition of aryl organometallic reagents to imines has emerged as one of the most powerful tools for the formation of optically active diarylmethylamines. Here, we report the first asymmetric reductive (hetero)arylations of imines using aryl and heteroaryl halides enabled by a chiral cobalt‐bisphosphine catalyst. This approach shows good functional group compatibility and complements the reported strategy without use of organometallic reagents. Mechanistic investigations supported that aryl‐cobalt, instead of an arylzinc reagent, was formed in situ in this reductive aryl‐addition event. [ABSTRACT FROM AUTHOR]

Two‐dimensional covalent organic frameworks (2D‐COFs) have emerged as attractive platforms for solar‐to‐chemical energy conversion. In this study, we have implemented a gradient heating strategy to synthesize a sp2‐carbon‐linked triazine‐based COF, COF‐JLU100, exhibiting high crystallinity, large surface area, good durability and carrier mobility for solar‐driven photocatalytic hydrogen evolution. The Pt‐doped COF‐JLU100 demonstrated a high hydrogen evolution rate of over 100 000 μmol g−1 h−1 for water splitting under visible‐light illumination (λ>420 nm). Experimental and theoretical studies corroborate that the cyano‐vinylene segments in COF‐JLU100 extend the π‐delocalization and enable fast charge transfer and separation rates as well as good dispersion in water. Moreover, COF‐JLU100 can be prepared by low‐cost and easily available monomers and has excellent stability, which is desirable for practical solar‐driven hydrogen production. [ABSTRACT FROM AUTHOR]

The 3d‐transition‐metal (hydro)oxides belong to a group of highly efficient, scalable and inexpensive electrocatalysts for widespread energy‐related applications that feature easily tailorable crystal and electronic structures. We propose a general strategy to further boost their electrocatalytic activities by introducing organic ligands into the framework, considering that most 3d‐metal (hydro)oxides usually exhibit quite strong binding with reaction intermediates and thus compromised activity due to the scaling relations. Involving weakly bonded ligands downshifts the d‐band center, which narrows the band gap, and optimizes the adsorption of these intermediates. For example, the activity of the oxygen evolution reaction (OER) can be greatly promoted by ≈5.7 times over a NiCo layered double hydroxide (LDH) after a terephthalic acid (TPA)‐induced conversion process, arising from the reduced energy barrier of the deprotonation of OH* to O*. Impressively, the proposed ligand‐induced conversion strategy is applicable to a series of 3d‐block metal (hydro)oxides, including NiFe2O4, NiCo2O4, and NiZn LDH, providing a general structural upgrading scheme for existing high‐performance electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have recently emerged as appealing platforms to construct microlasers owing to their compelling characters combining the excellent stability of inorganic materials and processable characters of organic materials. However, MOF microstructures developed thus far are generally composed of multiple edge boundaries due to their crystalline nature, which consequently raises significant scattering losses that are detrimental to lasing performance. In this work, we propose a strategy to overcome the above drawback by designing spherically shaped MOFs microcavities. Such spherical MOF microstructures are constructed by amorphizing MOFs with a topological distortion network through introducing flexible building blocks into the growth environment. With an ultra‐smooth surface and excellent circular boundaries, the acquired spherical microcavities possess a Q factor as high as ≈104 and can provide sufficient feedback for high‐quality single‐mode lasing oscillations. We hope that these results will pave an avenue for the construction of new types of flexible MOF‐based photonic components. [ABSTRACT FROM AUTHOR]