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It has long been an aspirational goal to create artificial channel structures that replicate the feat achieved by ion channel proteins. Biological ion channels occasionally demonstrate multiple conductance states (known as subconductance), remaining a challenging property to achieve in artificial channel molecules. We report a funnel‐shaped single‐molecule channel constructed by an electron‐deficient macrocycle and two electron‐deficient aromatic imide arms. Planar lipid bilayer measurements reveal distinct current recordings, including a closed state, two conducting states, and spontaneous transitions between the three states, resembling the events seen in biological ion channels. The transitions result from conformational changes induced by chloride transport in the channel molecule. Both opening states show a non‐linear and rectifying I–V relationship, indicating voltage‐dependent transport due to the asymmetrical channel structure. This work could enhance our understanding of ion permeation and channel opening mechanism. [ABSTRACT FROM AUTHOR]

Although dearomative functionalizations enable the direct conversion of flat aromatics into precious three‐dimensional architectures, the case for simple arenes remains largely underdeveloped owing to the high aromatic stabilization energy. We herein report a dearomative sequential addition of two nucleophiles to arene π‐bonds through umpolung of chromium–arene complexes. This mode enables divergent dearomative carbonylation reactions of benzene derivatives by tolerating various nucleophiles in combination with alcohols or amines under CO‐gas‐free conditions, thus providing modular access to functionalized esters or amides. The tunable synthesis of 1,3‐ or 1,4‐cyclohexadienes as well as the construction of carbon quaternary centers further highlight the versatility of this dearomatization. Diverse late‐stage modifications and derivatizations towards synthetically challenging and bioactive molecules reveal the synthetic utility. A possible mechanism was proposed based on control experiments and intermediate tracking. [ABSTRACT FROM AUTHOR]

Suffering from the susceptibility to decomposition, the potential electrochemical application of FeOCl has greatly been hindered. The rational design of the soft‐hard material interface can effectively address the challenge of stress concentration and thus decomposition that may occur in the electrodes during charging and discharging. Herein, interlayer structure manipulation of FeOCl/MXene using soft‐hard interface design method were conducted for electrochemical dechlorination. FeOCl was encapsulated in Ti3C2Tx MXene nanosheets by electrostatic self‐assembly layer by layer to form a soft‐hard mechanical hierarchical structure, in which Ti3C2Tx was used as flexible buffer layers to relieve the huge volume change of FeOCl during Cl− intercalation/deintercalation and constructed a conductive network for fast charge transfer. The CDI dechlorination system of FeOCl/Ti3C2Tx delivered outstanding Cl− adsorption capacity (158.47 ± 6.98 mg g−1), rate (6.07 ± 0.35 mg g−1 min−1), and stability (over 94.49 % in 30 cycles), and achieved considerable energy recovery (21.14 ± 0.25 %). The superior dechlorination performance was proved to originate from the Fe2+/Fe3+ topochemical transformation and the deformation constraint effect of Ti3C2Tx on FeOCl. Our interfacial design strategy enables a hard‐to‐soft integration capacity, which can serve as a universal technology for solving the traditional problem of electrode volume expansion. [ABSTRACT FROM AUTHOR]

The construction of organic–inorganic hybrid supramolecular polymers using polyoxometalate (POM) as building block is expected to bring new opportunities to the functionalization of supramolecular polymers and the development of novel POM‐based soft materials. Here, by using the orthogonal self‐assembly based on host–guest interactions and metal‐ligand interactions, we report the in situ construction of a novel POM‐based hybrid supramolecular polymer (POM‐SP) at the oil‐water interface, while the redox and competitive responsiveness can be triggered independently. Moreover, the binding energy of POM‐SP at the interface is sufficiently strong so that the assembly of POM‐SP jams, allowing the stabilization of liquids in nonequilibrium shapes, offering the possibility of fabricating all‐liquid constructs with reconfigurability. [ABSTRACT FROM AUTHOR]

The promotion of intersystem crossing (ISC) is critical for achieving a high‐efficiency long‐persistent luminescence (LPL) from organic materials. However, the use of a transition‐metal complex for LPL materials has not been explored because it can also shorten the emission lifetime by accelerating the phosphorescence decay. Here, we report a new class of LPL materials by doping a monovalent Au‐carbene complex into a boron‐embedded molecular host. The donor‐acceptor systems exhibit photoluminescence with both high efficiencies (>57 %) and long lifetimes (ca. 40 ms) at room temperature. It is revealed that the Au atom promotes the population of low‐lying triplet excited states of the host aggregate (T1*) which can be converted into the charge‐transfer (CT) state, thereby resulting in afterglow luminescence. Moreover, the use of a chirality unit on the guest molecule results in the LPL being circularly polarized. This work illustrates that transition‐metal complexes can be used for developing organic afterglow systems by exquisite control over the excited state mechanism. [ABSTRACT FROM AUTHOR]

The high local electron density and efficient charge carrier separation are two important factors to affect photocatalytic activity, especially for the CO2 photoreduction reaction. However, the systematic studies on the structure‐functional relationship regarding the above two factors based on precisely structure model are rarely reported. Herein, as a proof‐of‐concept, we developed a new strategy on the evaluation of local electron density by controlling the relative electron‐deficient (ED) and electron‐rich (ER) intensity of monomer at a molecular level based on three rational‐designed vinylene‐linked sp2 carbon‐covalent organic frameworks (COFs). As expected, the as‐prepared vinylene‐linked sp2 carbon‐conjugated metal‐covalent organic framework (MCOFs) (VL‐MCOF‐1) with molecular junction exhibited excellent activities for CO2‐to‐HCOOH conversion (283.41 μmol g−1 h−1) and high selectivity of 97.1 %, much higher than the VL‐MCOF‐2 and g‐C34N6‐COF, which is due to the synergistic effect of the multi‐electronic metal clusters (Cu3(PyCA)3) (PyCA=pyrazolate‐4‐carboxaldehyde) as strong ER roles and cyanopyridine units as ED roles and active sites, as well as the boosted photo‐induced charge separation efficiency of vinyl connection and increased light utilization ability. These results not only provide a strategy for regulating the electron‐density distribution of photocatalysts at the molecular level but also offers profound insights for metal clusters‐based COFs to effective CO2 conversion. [ABSTRACT FROM AUTHOR]

In this work, we innovatively assembled two types of traditional photosensitizers, that is pyridine ruthenium/ferrum (Ru(bpy)32+/Fe(bpy)32+) and porphyrin/metalloporphyrin complex (2HPor/ZnPor) by covalent linkage to get a series of dual photosensitizer‐based three‐dimensional metal‐covalent organic frameworks (3D MCOFs), which behaved strong visible light‐absorbing ability, efficient electron transfer and suitable band gap for highly efficient photocatalytic hydrogen (H2) evolution. Rubpy‐ZnPor COF achieved the highest H2 yield (30 338 μmol g−1 h−1) with apparent quantum efficiency (AQE) of 9.68 %@420 nm, which showed one of the best performances among all reported COF based photocatalysts. Furthermore, the in situ produced H2 was successfully tandem used in the alkyne hydrogenation with ≈99.9 % conversion efficiency. Theoretical calculations reveal that both the two photosensitizer units in MCOFs can be photoexcited and thus contribute optimal photocatalytic activity. This work develops a general strategy and shows the great potential of using multiple photosensitive materials in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

H2O2 photosynthesis coupled with biomass valorization can not only maximize the energy utilization but also realize the production of value‐added products. Here, a series of COFs (i.e. Cu3‐BT‐COF, Cu3‐pT‐COF and TFP‐BT‐COF) with regulated redox molecular junctions have been prepared to study H2O2 photosynthesis coupled with furfuryl alcohol (FFA) photo‐oxidation to furoic acid (FA). The FA generation efficiency of Cu3‐BT‐COF was found to be 575 mM g−1 (conversion ≈100 % and selectivity >99 %) and the H2O2 production rate can reach up to 187 000 μM g−1, which is much higher than Cu3‐pT‐COF, TFP‐BT‐COF and its monomers. As shown by theoretical calculations, the covalent coupling of the Cu cluster and the thiazole group can promote charge transfer, substrate activation and FFA dehydrogenation, thus boosting both the kinetics of H2O2 production and FFA photo‐oxidation to increase the efficiency. This is the first report about COFs for H2O2 photosynthesis coupled with biomass valorization, which might facilitate the exploration of porous‐crystalline catalysts in this field. [ABSTRACT FROM AUTHOR]