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A bis‐urea‐functionalized ditopic subcomponent assembled with 2‐formylpyridine and FeII, resulting in a dynamic library of metal–organic assemblies: an irregular FeII4L6 structure and three FeII2L3 stereoisomers: left‐ and right‐handed helicates and a meso‐structure. This library reconfigured in response to the addition of monosaccharide derivatives, which served as guests for specific library members, and the rate of saccharide mutarotation was also enhanced by the library. The (P) enantiomer of the FeII2L3 helical structure bound β‐D‐glucose selectively over α‐D‐glucose. As a consequence, the library collapsed into the (P)‐FeII2L3 helicate following glucose addition. The α‐D‐glucose was likewise transformed into the β‐D‐anomer during equilibration and binding. Thus, β‐D‐glucose and (P)‐3 amplified each other in the product mixture, as metal–organic and saccharide libraries geared together into a single equilibrating system. [ABSTRACT FROM AUTHOR]

Achieving a large dissymmetry factor (glum) is a challenge in the field of circularly polarized luminescence (CPL). A chiral charge‐transfer (CT) system consisting of chiral electron donor and achiral electron acceptor shows bright circularly polarized emission with large glum value. The chiral emissive CT complexes could be fabricated through various approaches, such as grinding, crystallization, spin coating, and gelatinization, by simply blending chiral donor and achiral acceptor. The structural synergy originating from π–π stacking and strong CT interactions resulted in the long‐range ordered self‐assembly, enabling the formation of supramolecular gels. Benefiting from the large magnetic dipole transition moment in the CT state, the CPL activity of CT complexes exhibited large circular polarization. Our design strategy of the chiral emissive CT complexes is expected to help the development of new molecular engineering strategies for designing highly efficient CPL‐active materials. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells have attracted widespread research effort because of their potential in portable electronics. The efficiency has exceeded 18 % owing to the high‐quality perovskite film achieved by various low‐temperature fabrication methods and matching of the interface and electrode materials. This Review focuses on recent progress in flexible perovskite solar cells concerning low‐temperature fabrication methods to improve the properties of perovskite films, such as full coverage, uniform morphology, and good crystallinity; demonstrated interface layers used in flexible perovskite solar cells, considering key figures‐of‐merit such as high transmittance, high carrier mobility, suitable band gap, and easy fabrication via low‐temperature methods; flexible transparent electrode materials developed to enhance the mechanical stability of the devices; mechanical and long‐term environmental stability; an outlook of flexible perovskite solar cells in portable electronic devices; and perspectives of commercialization for flexible perovskite solar cells based on cost. Flexible perovskite solar cells have attracted significant attention owing to their promising potential in practical applications. This Review discusses the prerequisite conditions for flexible perovskite solar cells, provides an outlook of flexible perovskite devices in portable electronic products, and estimates their production cost by roll‐to‐roll vacuum deposition for commercialization. [ABSTRACT FROM AUTHOR]

Abstract: Through mimicking both the chiral and energy transfer in an artificial self‐assembled system, not only was chiral transfer realized but also a dual upconverted and downconverted energy transfer system was created that emit circularly polarized luminescence. The individual chiral π‐gelator can self‐assemble into a nanofiber exhibiting supramolecular chirality and circularly polarized luminescence (CPL). In the presence of an achiral sensitizer PdII octaethylporphyrin derivative, both chirality transfer from chiral gelator to achiral sensitizer and triplet‐triplet energy transfer from excited sensitizer to chiral gelator could be realized. Upconverted CPL could be observed through a triplet–triplet annihilation photon upconversion (TTA‐UC), while downconverted CPL could be obtained from chirality‐transfer‐induced emission of the achiral sensitizer. The interplay between chiral energy acceptor and achiral sensitizer promoted the communication of chiral and excited energy information. [ABSTRACT FROM AUTHOR]

The development of flexible near-infrared (NIR) photovoltaic (PV) devices containing silicon meets the strong demands for solar utilization, portability, and sustainable manufacture; however, improvements in the NIR light absorption and conversion efficiencies in ultrathin crystalline Si are required. We have developed an approach to improve the quantum efficiency of flexible PV devices in the NIR spectral region by integrating Si nanowire arrays with plasmonic Ag nanoplates. The Ag nanoplates can directly harvest and convert NIR light into plasmonic hot electrons for injection into Si, while the Si nanowire arrays offer light trapping. Taking the wavelength of 800 nm as an example, the external quantum efficiency has been improved by 59 % by the integration Ag nanoplates. This work provides an alternative strategy for the design and fabrication of flexible NIR PVs. [ABSTRACT FROM AUTHOR]

Caged supramolecular systems are promising hosts for guest inclusion, separation, and stabilization. Well-studied examples are mainly metal-coordination-based or covalent architectures. An anion-coordination-based cage that is capable of encapsulating halocarbon guests is reported for the first time. This A4L4-type (A=anion) tetrahedral cage, [(PO4)4 L4]12−, assembled from a C3-symmetric tris(bisurea) ligand ( L) and phosphate ion (PO43−), readily accommodates a series of quasi-tetrahedral halocarbons, such as the Freon components CFCl3, CF2Cl2, CHFCl2, and C(CH3)F3, and chlorocarbons CH2Cl2, CHCl3, CCl4, C(CH3)Cl3, C(CH3)2Cl2, and C(CH3)3Cl. The guest encapsulation in the solid state is confirmed by crystal structures, while the host-guest interactions in solution were demonstrated by NMR techniques. [ABSTRACT FROM AUTHOR]

A persistent challenge in utilizing Au nanocrystals for surface‐enhanced Raman spectroscopy (SERS) lies in achieving controllable superstructures that maximize SERS performance. Here, a novel strategy is proposed to enhance the SERS performance by precisely adjusting the tip arrangements of Au nanobipyramids (BPs) in two‐dimensional (2D) superlattices (SLs). This is achieved through ligand‐exchange of Au BPs, followed by liquid‐air interfacial assembly, resulting in large‐area, transferrable SL membranes. The key to controlling the arrangement of Au BPs in the SLs is the regulation of the amount of free ligands added during self‐assembly, which allows for the precise formation of various configurations such as tilted SLs, tip‐on‐tip SLs, and tip‐to‐tip SLs. Among these configurations, tip‐on‐tip SLs exhibit the highest enhancement factor for SERS, reaching an impressive value of 1.95×108, with uniform and consistent SERS signals across a large area. The experimental findings are further corroborated by simulations using the finite element method. This study establishes an efficient method for engineering the microstructure of 2D SLs composed of Au BPs, highlighting the importance of fine‐tuning the tip arrangements of Au BPs to regulate SERS performance. [ABSTRACT FROM AUTHOR]

Lattice mismatch significantly influences microscopic transport in semiconducting devices, affecting interfacial charge behavior and device efficacy. This atomic‐level disordering, often overlooked in previous research, is crucial for device efficiency and lifetime. Recent studies have highlighted emerging challenges related to lattice mismatch in perovskite solar cells, especially at heterojunctions, revealing issues like severe tensile stress, increased ion migration, and reduced carrier mobility. This review systematically discusses the effects of lattice mismatch on strain, material stability, and carrier dynamics. It also includes detailed characterizations of these phenomena and summarizes current strategies including epitaxial growth and buffer layer, as well as explores future solutions to mitigate mismatch‐induced issues. We also provide the challenges and prospects for lattice mismatch, aiming to enhance the efficiency and stability of perovskite solar cells, and contribute to renewable energy technology advancements. [ABSTRACT FROM AUTHOR]

Functional thin films, being fabricated by incorporating discrete supramolecular architectures, have potential applications in research areas such as sensing, energy storage, catalysis, and optoelectronics. Here, we have determined that an anion‐coordinated triple helicate can be solution‐processed into a functional thin film by incorporation into a polymethyl methacrylate (PMMA) matrix. The thin films fabricated by the incorporation of the anion‐coordinated triple helicate show multiple optical properties, such as fluorescence, CD, and CPL. In addition, the film has the ability to recognize choline and choline derivatives in a water system. The successful recognition of Ch+ by the film represents the first example of utilizing 'aniono'‐supramolecular architectures for biomolecule detection in aqueous solution and opens up a new route for designing biocompatible functional materials. [ABSTRACT FROM AUTHOR]

Sulfur incorporation into natural products is a critical area of biosynthetic studies. Recently, a subset of sulfur‐containing angucyclines has been discovered, and yet, the sulfur incorporation step is poorly understood. In this work, a series of thioether‐bridged angucyclines were discovered, and a cryptic epoxide Michael acceptor intermediate was revealed en route to thioangucyclines (TACs) A and B. However, systematic gene deletion of the biosynthetic gene cluster (BGC) by CRISPR/Cas9 could not identify any gene responsible for the conversion of the epoxide intermediate to TACs. Instead, a series of in vitro and in vivo experiments conclusively showed that the conversion is the result of two non‐enzymatic steps, possibly mediated by endogenous hydrogen sulfide. Therefore, the TACs are proposed to derive from a detoxification process. These results are expected to contribute to the study of both angucyclines and the utilization of inorganic sulfur in natural product biosynthesis. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) with structural designability and tunability of photophysical properties enable them to be a promising class of organic luminescent materials by incorporating well‐designed fluorescent units directly into the periodic skeletons. The photophysical properties of COFs are mainly affected by the structural features, which determine the conjugation degree, charge delocalization ability, and exciton dynamics of COFs. To understand the relationship between COF structures and their photophysical properties, two COFs with the same pyrene chromophore units but different linkages (imine or vinylene) were designed and synthesized. Interestingly, different linkages endow COFs with huge differences in solid‐state photoluminescence quantum yield (PLQY) for imine‐ and vinylene‐linked pyrene‐based COFs, which possess PLQY values of 0.34 % and 15.43 %, respectively. The femtosecond‐transient absorption spectra and time‐dependent density functional theory reveal the different charge‐transfer pathways in imine‐ and vinylene‐linked COFs, which influence the exciton relaxation way and fluorescence intensity. In addition, an effective white‐light device was obtained by coating the vinylene‐linked COF on a light‐emitting diode strip. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells (FPSCs) with excellent recoverability show a wide range of potential applications in portable power sources. The recoverability of FPSCs requires outstanding bendability of each functional layer, including the flexible substrates, electrodes, perovskite light absorbers, and charge transport materials. This review highlights the recent progress and practical applications of high‐recoverability FPSCs, and illustrates the routes toward improvement of the recoverability and environmental stability through the choice of flexible substrates and the preparation of high‐quality perovskite films, as well as the optimization of charge‐selective contacts. In addition, we explore the intrinsic properties of each functional layer from the physical perspective and analyze how to select suitable functional layers. Additionally, some effective strategies are summarized, including material modification engineering of selective contacts, additives and interface engineering of interlayers, which can release mechanical stress and increase the power‐conversion efficiency (PCE) and recoverability of the FPSCs. The challenges of making high‐performance FPSCs with long‐term stability and high recoverability are discussed. Finally, future applications and perspectives for FPSCs are discussed, aiming to promote more extensive commercialization processes for lightweight and durable FPSCs. [ABSTRACT FROM AUTHOR]

Constructing a powerful photocatalytic system that can achieve the carbon dioxide (CO2) reduction half‐reaction and the water (H2O) oxidation half‐reaction simultaneously is a very challenging but meaningful task. Herein, a porous material with a crystalline topological network, named viCOF‐bpy‐Re, was rationally synthesized by incorporating rhenium complexes as reductive sites and triazine ring structures as oxidative sites via robust −C=C− bond linkages. The charge‐separation ability of viCOF‐bpy‐Re is promoted by low polarized π‐bridges between rhenium complexes and triazine ring units, and the efficient charge‐separation enables the photogenerated electron–hole pairs, followed by an intramolecular charge‐transfer process, to form photogenerated electrons involved in CO2 reduction and photogenerated holes that participate in H2O oxidation simultaneously. The viCOF‐bpy‐Re shows the highest catalytic photocatalytic carbon monoxide (CO) production rate (190.6 μmol g−1 h−1 with about 100 % selectivity) and oxygen (O2) evolution (90.2 μmol g−1 h−1) among all the porous catalysts in CO2 reduction with H2O as sacrificial agents. Therefore, a powerful photocatalytic system was successfully achieved, and this catalytic system exhibited excellent stability in the catalysis process for 50 hours. The structure–function relationship was confirmed by femtosecond transient absorption spectroscopy and density functional theory calculations. [ABSTRACT FROM AUTHOR]

The slow reaction kinetics and structural instability of organic electrode materials limit the further performance improvement of aqueous zinc‐organic batteries. Herein, we have synthesized a Z‐folded hydroxyl polymer polytetrafluorohydroquinone (PTFHQ) with inert hydroxyl groups that could be partially oxidized to the active carbonyl groups through the in situ activation process and then undertake the storage/release of Zn2+. In the activated PTFHQ, the hydroxyl groups and S atoms enlarge the electronegativity region near the electrochemically active carbonyl groups, enhancing their electrochemical activity. Simultaneously, the residual hydroxyl groups could act as hydrophilic groups to enhance the electrolyte wettability while ensuring the stability of the polymer chain in the electrolyte. Also, the Z‐folded structure of PTFHQ plays an important role in reversible binding with Zn2+ and fast ion diffusion. All these benefits make the activated PTFHQ exhibit a high specific capacity of 215 mAh g−1 at 0.1 A g−1, over 3400 stable cycles with a capacity retention of 92 %, and an outstanding rate capability of 196 mAh g−1 at 20 A g−1. [ABSTRACT FROM AUTHOR]

Hydrophobic tagging (HyT) is a potential therapeutic strategy for targeted protein degradation (TPD). Norbornene was discovered as an unprecedented hydrophobic tag in this study and was used to degrade the anaplastic lymphoma kinase (ALK) fusion protein by linking it to ALK inhibitors. The most promising degrader, Hyt‐9, potently reduced ALK levels through Hsp70 and the ubiquitin−proteasome system (UPS) in vitro without compensatory upregulation of ALK. Furthermore, Hyt‐9 exhibited a significant tumor‐inhibiting effect in vivo with moderate oral bioavailability. More importantly, norbornene can also be used to degrade the intractable enhancer of zeste homolog 2 (EZH2) when tagged with the EZH2 inhibitor tazemetostat. Thus, the discovery of novel hydrophobic norbornene tags shows promise for the future development of TPD technology. [ABSTRACT FROM AUTHOR]

Three tetrahedral organic cages have been obtained by condensing a triamino linker with a set of three ostensibly analogous triformyl precursors. Despite the large number of imine bonds formed, the corresponding cages were obtained in exceptionally high yields. Both theory and experimental results demonstrate that intramolecular CH⋅⋅⋅π interactions within all of the cage frameworks play an important role in abetting the condensations and contributing to the near-quantitative synthetic yields. The three cages of this study exhibit high thermodynamic and kinetic stability. A variety of small neutral guest molecules with complementary sizes and geometries may be used as templates in the cage forming reactions. Among the guests that may be used in this way is white phosphorus (P4), whose inherent reactivity towards oxygen is almost fully attenuated when bound within one of the cages. [ABSTRACT FROM AUTHOR]

To enhance the fluorescence efficiency of semiconductor nanocrystal quantum dots (QDs), strategies via enhancing photo‐absorption and eliminating non‐radiative relaxation have been proposed. In this study, we demonstrate that fluorescence efficiency of molybdenum disulfide quantum dots (MoS2 QDs) can be enhanced by single‐atom metal (Au, Ag, Pt, Cu) modification. Four‐fold enhancement of the fluorescence emission of MoS2 QDs is observed with single‐atom Au modification. The underlying mechanism is ascribed to the passivation of non‐radiative surface states owing to the new defect energy level of Au in the forbidden band that can trap excess electrons in n‐type MoS2, increasing the recombination probability of conduction band electrons with valence band holes of MoS2. Our results open an avenue for enhancing the fluorescence efficiency of QDs via the modification of atomically dispersed metals, and extend their scopes and potentials in a fundamental way for economic efficiency and stability of single‐atom metals. [ABSTRACT FROM AUTHOR]

The fabrication of anion‐coordinated assemblies into functional soft materials remains a major challenge. To this end, four C2‐symmetric anion‐binding ligands equipped with ortho‐phenylene‐bridged bis(urea) and amine or amide ends were designed, which generated A2L3 triple helical architectures upon self‐assembly with phosphate ions. Hierarchical intermolecular hydrogen bonds among the terminal amine/amide groups and urea moieties resulted in the formation of functional gels. The obtained gels were further applied for conductive adhesion between different surfaces, displaying excellent flexibility and selective wettability. The viscoelastic gels constructed from anion‐coordinated assemblies described in this work represent the first example of a new class of anion‐coordination‐driven smart materials. [ABSTRACT FROM AUTHOR]

Surface defects have been a key constraint for perovskite photovoltaics. Herein, 1,3‐dimethyl‐3‐imidazolium hexafluorophosphate (DMIMPF6) ionic liquid (IL) is adopted to passivate the surface of a formamidinium‐cesium lead iodide perovskite (Cs0.08FA0.92PbI3) and also reduce the energy barrier between the perovskite and hole transport layer. Theoretical simulations and experimental results demonstrate that Pb‐cluster and Pb‐I antisite defects can be effectively passivated by [DMIM]+ bonding with the Pb2+ ion on the perovskite surface, leading to significantly suppressed non‐radiative recombination. As a result, the solar cell efficiency was increased to 23.25 % from 21.09 %. Meanwhile, the DMIMPF6‐treated perovskite device demonstrated long‐term stability because the hydrophobic DMIMPF6 layer blocked moisture permeation. [ABSTRACT FROM AUTHOR]

Propane dehydrogenation (PDH) has great potential to meet the increasing global demand for propylene, but the widely used Pt‐based catalysts usually suffer from short‐term stability and unsatisfactory propylene selectivity. Herein, we develop a ligand‐protected direct hydrogen reduction method for encapsulating subnanometer bimetallic Pt–Zn clusters inside silicalite‐1 (S‐1) zeolite. The introduction of Zn species significantly improved the stability of the Pt clusters and gave a superhigh propylene selectivity of 99.3 % with a weight hourly space velocity (WHSV) of 3.6–54 h−1 and specific activity of propylene formation of 65.5 molC3H6 gPt−1 h−1 (WHSV=108 h−1) at 550 °C. Moreover, no obvious deactivation was observed over PtZn4@S‐1‐H catalyst even after 13000 min on stream (WHSV=3.6 h−1), affording an extremely low deactivation constant of 0.001 h−1, which is 200 times lower than that of the PtZn4/Al2O3 counterpart under the same conditions. We also show that the introduction of Cs+ ions into the zeolite can improve the regeneration stability of catalysts, and the catalytic activity kept unchanged after four continuous cycles. [ABSTRACT FROM AUTHOR]

The lithium (Li)–air battery has an ultrahigh theoretical specific energy, however, even in pure oxygen (O2), the vulnerability of conventional organic electrolytes and carbon cathodes towards reaction intermediates, especially O2−, and corrosive oxidation and crack/pulverization of Li metal anode lead to poor cycling stability of the Li‐air battery. Even worse, the water and/or CO2 in air bring parasitic reactions and safety issues. Therefore, applying such systems in open‐air environment is challenging. Herein, contrary to previous assertions, we have found that CO2 can improve the stability of both anode and electrolyte, and a high‐performance rechargeable Li–O2/CO2 battery is developed. The CO2 not only facilitates the in situ formation of a passivated protective Li2CO3 film on the Li anode, but also restrains side reactions involving electrolyte and cathode by capturing O2−. Moreover, the Pd/CNT catalyst in the cathode can extend the battery lifespan by effectively tuning the product morphology and catalyzing the decomposition of Li2CO3. The Li–O2/CO2 battery achieves a full discharge capacity of 6628 mAh g−1 and a long life of 715 cycles, which is even better than those of pure Li–O2 batteries. [ABSTRACT FROM AUTHOR]

By constructing a supramolecular light‐harvesting chiral nanotube in the aqueous phase, we demonstrate a cooperative energy and chirality transfer. It was found that a cyanostilbene‐appended glutamate compound (CG) self‐assembled into helical nanotubes exhibiting both supramolecular chirality and circularly polarized luminescence (CPL). When two achiral acceptors, ThT and AO, with different energy bands were co‐assembled with the nanotube, the CG nanotube could transfer its chirality to both of the acceptors. The excitation energy could be transferred to ThT but only be sequentially transferred to AO. During this process, the CPL ascribed to the acceptor could be sequentially amplified. This work provides a new insight into the understanding the cooperative chirality and energy transfer in a chiral supramolecular system, which is similar to the natural light‐harvesting antennas. On the other hand: When the achiral acceptors thioflavin T (ThT) and acridine orange (AO), with different energy bands, were co‐assembled with the nanotube CG it could transfer its chirality to both of the acceptors to give an enhancement of acceptor circularly polarized luminescence (CPL). The excitation energy could be transferred to ThT but only be sequentially transferred to AO. [ABSTRACT FROM AUTHOR]

Abstract: An anion‐coordination‐based A4L6 (“A” denotes anion and “L” is ligand) tetrahedral cage was constructed by a C2‐symmetric bis‐bis(urea) ligand and phosphate anion, which showed reversible interconversion with the A2L3 triple helicate as a response to the template, concentration, or solvent. Notably, an unusual “peripheral” templation was found to be critical to stabilize the tetrahedral structure. This peripheral effect was utilized to assemble an “empty” A4L6 cage that allows the multi‐stimuli‐controlled capture/release of biologically important species such as choline and acetylcholine. [ABSTRACT FROM AUTHOR]

Adhesives, Gels, Self-Assembly, Anion Coordination, Hydrogen Bonding Inside Back Cover: Hierarchical Self-Assembly of Adhesive and Conductive Gels with Anion-Coordinated Triple Helicate Junctions (Angew. Keywords: Adhesives; Anion Coordination; Gels; Hydrogen Bonding; Self-Assembly EN Adhesives Anion Coordination Gels Hydrogen Bonding Self-Assembly 1 1 1 05/18/22 20220523 NES 220523 B The hierarchical self-assembly b of functional gels with anion-coordinated architecture junctions will open up a new avenue for the design and fabrication of a broad range of smart materials. [Extracted from the article]

Boron–nitrogen units were incorporated into thiophene‐fused polycyclic aromatic compounds. Organic field‐effect transistors based on these azaborine compounds were fabricated, demonstrating a novel engineering concept of organic semiconductors and providing opportunities of a broad class of BN‐containing compounds for application in future organic electronic devices (see picture; μFET=hole mobility). [ABSTRACT FROM AUTHOR]