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The recent discovery of frustrated Lewis pairs (FLPs) during the activation of small molecules has inspired extensive research across the full span of chemical science. Owing to the nature of weak interactions, it is experimentally challenging to directly observe and modulate FLP at the molecular scale. Here we design a boron cluster anion building block (B 10 H 8 2- ) and organic amine cations ([NR 4 ] + , R=-CH 3 , -C 2 ) as the FLP to prove the feasibility of controlling their interaction in the electric double layer (EDL) via an electrochemical strategy. In situ single-molecule electrical measurements and Raman monitoring of B 5 ) as the FLP to prove the feasibility of controlling their interaction in the electric double layer (EDL) via an electrochemical strategy. In situ single-molecule electrical measurements and Raman monitoring of B 10 H 8 2- -[NR 4 ] + near or below the potential of zero charge (PZC). Furthermore, this FLP chemistry leads to a shift in the local density of states of boron clusters towards the E 10 for enhancing electron transport, providing a new prototype of a reversible single-cluster switch that digitally switches upon controlling FLP chemistry in the electric double layer.8 2- near or below the potential of zero charge (PZC). Furthermore, this FLP chemistry leads to a shift in the local density of states of boron clusters towards the E F for enhancing electron transport, providing a new prototype of a reversible single-cluster switch that digitally switches upon controlling FLP chemistry in the electric double layer., (© 2024 Wiley-VCH GmbH.)

To study the effect of a dye on the photoluminescence (PL) properties of metal complexes, a series of gold(I) complexes were synthesized, containing a 7-amino-4-methylcoumarin luminophore. The complexes are comprised of a coumarin moiety featuring different ancillary ligands, specifically N-heterocyclic carbenes, triphenylphosphine, and diphenyl-2-pyridylphosphine. The synthesized gold(I) complexes are luminescent both in solution and the solid state at room temperature and 77 K. Complexes of different nuclearity, i.e., mono-, di- and trinuclear compounds were synthesized. A clear trend between the nuclearity and the quantum yields can be seen. The coumarin dye not only improves the PL properties, but also enhances the luminescence of trinuclear clusters, which are otherwise known to be weak emitters in solution. The optical absorption properties were investigated in detail by quantum chemical calculations., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The introduction of 4,5-dihydroazuleno[2,1,8-ija]azulene as a central core between two 1,4-dithiafulvene (DTF) units provides a novel class of extended tetrathiafulvalene (TTF) electron donors. Herein we present the synthesis of such compounds with the azulenoazulene further expanded by annulation to benzene, naphthalene, or thiophene rings. Moreover, unsymmetrical donor-acceptor chromophores with one DTF and one carbonyl at the central core are presented. The effect of the odd-membered rings of the polycyclic aromatic hydrocarbon cores on the geometrical features and the extent of bond conjugation in these systems were investigated by UV/Vis absorption spectroscopy, (spectro)electrochemical studies, X-ray and electron diffraction, and computational studies. Altogether these studies reveal that, upon oxidation, the non-planar core of the bis(benzo)-fused dihydro-azulenoazulene-extended TTF generates a large 22π-aromatic system (together with two 6π-aromatic 1,3-dithiolium appendages) characterized by significant bond length equalizations. The dication formed by oxidation is EPR silent, indicating a singlet ground state. Computations reveal that the closed-shell singlet species and its open-shell singlet counterpart are nearly degenerate and of lower energy than a triplet species. According to cyclic voltammetry, the compounds can be oxidized further and present multi-redox systems., (© 2024 Wiley-VCH GmbH.)

Precision graphene nanoribbons (GNRs) offer distinctive physicochemical properties that are highly dependent on their geometric topologies, thereby holding great potential for applications in carbon-based optoelectronics and spintronics. While the edge structure and width control has been a popular strategy for engineering the optoelectronic properties of GNRs, non-hexagonal-ring-containing GNRs remain underexplored due to synthetic challenges, despite offering an equally high potential for tailored properties. Herein, we report the synthesis of a wavy GNR (wGNR) by embedding periodic eight-membered rings into its carbon skeleton, which is achieved by the A 2 B 2 -type Diels-Alder polymerization between dibenzocyclooctadiyne (6) and dicyclopenta[e,l]pyrene-5,11-dione derivative (8), followed by a selective Scholl reaction of the obtained ladder-type polymer (LTP) precursor. The obtained wGNR, with a length of up to 30 nm, has been thoroughly characterized by solid-state NMR, FT-IR, Raman, and UV/Vis spectroscopy with the support of DFT calculations. The non-planar geometry of wGNR efficiently prevents the inter-ribbon π-π aggregation, leading to photoluminescence in solution. Consequently, the wGNR can function as an emissive layer for organic light-emitting electrochemical cells (OLECs), offering a proof-of-concept exploration in implementing luminescent GNRs into optoelectronic devices. The fast-responding OLECs employing wGNR will pave the way for advancements in OLEC technology and other optoelectronic devices., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

With ordered and periodic network structures, adjustable pore sizes and high chemical stability, covalent organic frameworks (COFs) have drawn much attention for the fabrication of superior separation membranes. However, it is challenging to prepare COF membranes with a molecular sieving property for gas separation due to their relatively large pore size. In this work, we develop the MOF-in-COF concept for vacuum-assisted synthesis of metal-organic framework (MOF) ZIF-8 inside the pores of TB-COF formed from trihydroxy-benzene-tricarbaldehyde (T) and diamino-biphenyl-disulfonic acid (B), thus constructing a novel ZIF-8@TB-COF membrane. Attributing to the formation of a well-defined one-dimensional (1D) nanoscale transport channel, the ZIF-8@TB-COF membrane displays a high hydrogen permselectivity. At 100 °C and 200 kPa, the mixture separation factors of H 2 /CO 2 , H 2 /CH 4 and H 2 /C 3 H 8 are 21.9, 63.1 and 134.4, respectively, which are much higher than those of the pristine TB-COF membrane due to the precise size sieving channels brought about by the incorporated MOF. The synthesis of ZIF-67@TB-COF membrane demonstrates the versatility of the synthesis strategy., (© 2024 Wiley-VCH GmbH.)

Metal-organic framework (MOF)-based membranes excel in molecular separation, attracting significant research interest. The crystallographic microstructure and selective adsorption capacity of MOFs closely correlate with their gas separation performance. Here, aniline was added to the ZIF-8 synthesis in varying concentrations. Aniline, encapsulated within ZIF-8 cavities, interacts strongly with the 2-methylimidazole linker, resulting in both a shift in crystallographic phase from I_43 m to Cm in Rietveld refinement of X-ray diffraction (XRD) patterns and the selective adsorption behavior between propylene and propane. Consequently, an aniline decorative ZIF-8 (Ani x -ZIF-8) membrane was prepared using a fast current-driven synthesis method, which exhibits good propylene/propane separation selectivity of up to 85. Calculation of the interaction energy between aniline and the various crystallographic phases of ZIF-8 using density functional theory (DFT) further verifies that aniline not only promotes the formation of crystallographic Cm phase, but also enhances the adsorption selectivity of propylene over propane. Aniline modification effectively tunes the crystallographic microstructure of ZIF-8, thereby, improving molecular sieving capabilities., (© 2024 Wiley-VCH GmbH.)

Riboswitches control gene regulation upon external stimuli such as environmental factors or ligand binding. The fluoride sensing riboswitch from Thermotoga petrophila is a complex regulatory RNA proposed to be involved in resistance to F - cytotoxicity. The details of structure and dynamics underpinning the regulatory mechanism are currently debated. Here we demonstrate that a combination of pulsed electron paramagnetic resonance (ESR/EPR) spectroscopies, detecting distances in the angstrom to nanometre range, can probe distinct regions of conformational flexibility in this riboswitch. PELDOR (pulsed electron-electron double resonance) revealed a similar preorganisation of the sensing domain in three forms, i.e. the free aptamer, the Mg 2+ -bound apo, and the F - -bound holo form. 19 F ENDOR (electron-nuclear double resonance) was used to investigate the active site structure of the F - -bound holo form. Distance distributions without a priori structural information were compared with in silico modelling of spin label conformations based on the crystal structure. While PELDOR, probing the periphery of the RNA fold, revealed conformational flexibility of the RNA backbone, ENDOR indicated low structural heterogeneity at the ligand binding site. Overall, the combination of PELDOR and ENDOR with sub-angstrom precision gave insight into structural organisation and flexibility of a riboswitch, not easily attainable by other biophysical techniques., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Copper-exchanged zeolite omega (Cu-omega) is a potent material for the selective conversion of methane-to-methanol (MtM) via the oxygen looping approach. However, its performance exhibits substantial variation depending on the operational conditions. Under an isothermal temperature regime, Cu-omega demonstrates subdued activity below 230 °C, but experiences a remarkable increase in activity at 290 °C. Applying a high-temperature activation protocol at 450 °C causes a rapid deactivation of the material. This behavioral divergence is investigated by combining reactivity studies, neutron diffraction and in situ high-resolution anomalous X-ray powder diffraction (HR-AXRPD), as well as electron paramagnetic resonance spectroscopy, to reveal that the migration of Cu throughout the framework is the primary cause of these behaviors, which in turn is predominantly governed by the degree of hydration of the system. This work suggests that control over the Cu migration throughout the zeolite framework may be harnessed to significantly increase the activity of Cu-omega by generating more active sites for the MtM conversion. These results underscore the power of in situ HR-AXRPD for unraveling the behavior of materials under reaction conditions and suggest that a re-evaluation of Cu-zeolites priorly deemed inactive for the MtM conversion across a broader range of conditions and looping protocols may be warranted., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

2-Bromo-1-(3,3-dinitroazetidin-1-yl)ethan-1-one (RRx-001) is a hypoxic cell chemotherapeutics with already demonstrated synergism in combined chemo-radiation therapy. The interaction of the compound with secondary low-energy electrons formed in large amounts during the physico-chemical phase of the irradiation may lead to these synergistic effects. The present study focuses on the first step of RRx-001 interaction with low-energy electrons in which a transient anion is formed and fragmented. Combination of two experiments allows us to disentangle the decay of the RRx-001 anion on different timescales. Sole presence of the electron initiates rapid dissociation of NO 2 and HNO 2 neutrals while NO 2 - and Br - ) and σ*(C-Br) states explains the experimental spectra. The fast dynamics monitored will impact the condensed phase chemistry of the anion as well.2 ) and σ*(C-Br) states explains the experimental spectra. The fast dynamics monitored will impact the condensed phase chemistry of the anion as well., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea-salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br - ) by O 2 and H 2 O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br - , O 2 and H 3 O + could spontaneously generate Br and HO 2 radicals through a proton-electron transfer process at the air-water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br - and the production of Br 2 . The estimated gaseous Br 2 production rate was up to 1.55×10 10  molecules cm -2  ⋅ s -1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br - activation could promote the multiphase oxidation of SO 2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br - activation. Our findings highlight the crucial role of the proton-electron transfer process in Br 2 production; here, H 3 O + facilitates the activation of Br - by O 2 , serves as a significant source of atmospheric reactive bromine and exerts a profound impact on the atmospheric oxidation capacity., (© 2024 Wiley-VCH GmbH.)

The charging behavior of molecular Au clusters protected by alkanethiolate (SC n H 2n+1 =SCn) is, under electrochemical conditions, significantly affected by the penetration of solvents and electrolytes into the SCn layer. In this study, we estimated the charging energy E C (n) associated with [PtAu 24 (SCn) 18 ] - +e - →[PtAu 24 (SCn) 18 ] 2- (n=4, 8, 12, and 16) in vacuum using mass-selected gas-phase anion photoelectron spectroscopy of [PtAu 24 (SCn) 18 ] z (z=-1 and -2). The E C (n) values of PtAu 24 (SCn) 18 in vacuum are significantly larger than those in solution and decrease with n in contrast to the behavior reported for Au 25 (SCn) 18 in solution. The effective relative permittivity (ϵ m *) of the SCn layer in vacuum is estimated to be 2.3-2.0 based on the double-concentric-capacitor model. Much smaller ϵ m * values in vacuum than those in solution are explained by the absence of solvent/electrolyte penetration into the monolayer. The gradual decrease of ϵ m * with n is ascribed to the appearance of an exposed surface region due to the bundle formation of long alkyl chains., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The concepts of sustainability and sustainable chemistry have attracted increasing attention in recent years, being of great importance to the younger generation. In this Viewpoint Article, we share how early-career chemists can contribute to the sustainable transformation of their discipline. We identify ways in which they can engage to catalyse action for change. This article does not attempt to answer questions about the most promising or pressing areas driving research and chemical innovation in the context of sustainability. Instead, we want to inspire and engage early-career chemists in pursuing sustainable actions by showcasing opportunities in education, outreach and policymaking, research culture and publishing, while highlighting existing challenges and the complexity of the topic. We want to empower early-career chemists by providing resources and ideas for engagement for a sustainable future globally. While the article focuses on students and early-career chemists, it provides insights to further stimulate the engagement of scientists from diverse backgrounds., (© 2024 Wiley-VCH GmbH.)

Optoacoustic (or photoacoustic) imaging promises micron-resolution noninvasive bioimaging with much deeper penetration (>cm) than fluorescence. However, optoacoustic imaging of enzyme activity would require loud, photostable, NIR-absorbing molecular contrast agents, which remain unknown. Most organic molecular contrast agents are repurposed fluorophores, with severe shortcomings of photoinstability or phototoxicity under optoacoustic imaging, as consequences of their slow S 1 →S 0 electronic relaxation. We now report that known fluorophores can be rationally modified to reach ultrafast S 1 →S 0 rates, without much extra molecular complexity, simply by merging them with molecular switches. Here, we merge azobenzene switches with cyanine dyes to give ultrafast relaxation (<10 ps, >100-fold faster). Without even adapting instrument settings, these azohemicyanines display outstanding improvements in signal longevity (>1000-fold increase of photostability) and signal loudness (>3-fold even at time zero). We show why this simple but unexplored design strategy can still offer stronger performance in the future, and can also increase the spatial resolution and the quantitative linearity of photoacoustic response over extended longitudinal imaging. By bringing the world of molecular switches and rotors to bear on problems facing optoacoustic agents, this practical strategy will help to unleash the full potential of optoacoustic imaging in fundamental studies and translational uses., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Elastomeric solid polymer electrolytes (SPEs) are highly promising to address the solid-solid-interface issues of solid-state lithium metal batteries (LMBs), but compromises have to be made to balance the intrinsic trade-offs among their conductive, resilient and recyclable properties. Here, we propose a dual-bond crosslinking strategy for SPEs to realize simultaneously high ionic conductivity, elastic resilience and recyclability. An elastomeric SPE is therefore designed with hemiaminal dynamic covalent networks and Li + -dissociation co-polymer chains, where the -C-N- bond maintains the load-bearing covalent network under stress but is chemically reversible through a non-spontaneous reaction, the weaker intramolecular hydrogen bond is mechanically reversible, and the soft chains endow the rapid ion conduction. With this delicate structure, the optimized SPE elastomer achieves high elastic resilience without loading-unloading hysteresis, outstanding ionic conductivity of 0.2 mS cm -1 (25 °C) and chemical recyclability. Then, exceptional room-temperature performances are obtained for repeated Li plating/stripping tests, and stable cycling of LMBs with either LiFePO 4 or 4.3 V-class LiFe 0.2 Mn 0.8 PO 4 cathode. Furthermore, the recycled and reprocessed SPEs can be circularly reused in LMBs without significant performance degradation. Our findings provide an inspiring design principle for SPEs to address the solid-solid-interface and sustainability challenges of solid-state LMBs., (© 2024 Wiley-VCH GmbH.)

The extent to which electrophores covalently bridged by a saturated linker are electrochemically independent was investigated considering the charge/spin duality of the electron and functionality of the electrophore as a spin carrier upon reduction. By combining computational modeling with electrochemical experiments, we investigated the mechanism by which tethered electrophores react together within 4,4'-oligo[n]methylene-bipyridinium assemblies (with n=2 to 5). We show that native dicationic electrophores (redox state Z=+2) are folded prior to electron injection into the system, allowing the emergence of supra-molecular orbitals (supra-MOs) likely to support the process of the reductive σ bond formation giving cyclomers. Indeed, for Z=+2, London Dispersion (LD) forces contribute to flatten the potential energy surface such that all-trans and folded conformers are approximately isoenergetic. Then, upon one-electron injection, for radical cations (Z=+1), LD forces significantly stabilize the folded conformers, except for the ethylene derivative deprived of supra-MOs. For radical cations equipped with supra-MOs, the unpaired electron is delocalized over both heterocycles through space. Cyclomer completion (Z=0) upon the second electron transfer occurs according to the inversion of redox potentials. This mechanism explains why intramolecular reactivity is favored and why pyridinium electrophores are not independent., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The development of improved solid electrolytes (SEs) plays a crucial role in the advancement of bulk-type solid-state battery (SSB) technologies. In recent years, multicomponent or high-entropy SEs are gaining increased attention for their advantageous charge-transport and (electro)chemical properties. However, a comprehensive understanding of how configurational entropy affects ionic conductivity is largely lacking. Herein we investigate a series of multication-substituted lithium argyrodites with the general formula Li 6+x [M1 a M2 b M3 c M4 d ]S 5 I, with M being P, Si, Ge, and Sb. Structure-property relationships related to ion mobility are probed using a combination of diffraction techniques, solid-state nuclear magnetic resonance spectroscopy, and charge-transport measurements. We present, to the best of our knowledge, the first experimental evidence of a direct correlation between occupational disorder in the cationic host lattice and lithium transport. By controlling the configurational entropy through compositional design, high bulk ionic conductivities up to 18 mS cm -1 at room temperature are achieved for optimized lithium argyrodites. Our results indicate the possibility of improving ionic conductivity in ceramic ion conductors via entropy engineering, overcoming compositional limitations for the design of advanced electrolytes and opening up new avenues in the field., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Organic-inorganic heterostructures play a pivotal role in modern electronic and optoelectronic applications including photodetectors and field effect transistors, as well as in solar energy conversion such as photoelectrodes of dye-sensitized solar cells, photoelectrochemical cells, and in organic photovoltaics. To a large extent, performance of such devices is controlled by charge transfer dynamics at and across (inner) interfaces, e.g., between a wide band gap semiconductor and molecular sensitizers and/or catalysts. Hence, a detailed understanding of the structure-dynamics-function relationship of such functional interfaces is necessary to rationalize possible performance limitations of these materials and devices on a molecular level. Vibrational sum-frequency generation (VSFG) spectroscopy, as an interface-sensitive spectroscopic technique, allows to obtain chemically specific information from interfaces and combines such chemical insights with ultrafast time resolution, when integrated as a spectroscopic probe into a pump-probe scheme. Thus, this minireview discusses the advantages and potential of VSFG spectroscopy for investigating interfacial charge transfer dynamics and structural changes at inner interfaces. A critical perspective of the unique spectroscopic view of otherwise inaccessible interfaces is presented, which we hope opens new opportunities for an improved understanding of function-determining processes in complex materials, and brings together communities who are devoted to designing materials and devices with spectroscopists., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

We report on the synthesis and characterization of a series of (mostly) air-stable diorganyl bis(pyridylimino) isoindolide (BPI) aluminum complexes and their chemistry upon visible-light excitation. The redox non-innocent BPI pincer ligand allows for efficient charge transfer homolytic processes of the title compounds. This makes them a universal platform for the generation of carbon-centered radicals. The photo-induced homolytic cleavage of the Al-C bonds was investigated by means of stationary and transient UV/Vis spectroscopy, spin trapping experiments, as well as EPR and NMR spectroscopy. The experimental findings were supported by quantum chemical calculations. Reactivity studies enabled the utilization of the aluminum complexes as reactants in tin-free Giese-type reactions and carbonyl alkylations under ambient conditions, which both indicated radical-polar crossover behavior. A deeper understanding of the physical fundamentals and photochemical process was provided, furnishing in turn a new strategy to control the reactivity of bench-stable aluminum organometallics., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Magnesium (Mg) batteries hold promise as a large-scale energy storage solution, but their progress has been hindered by the lack of high-performance cathodes. Here, we address this challenge by unlocking the reversible four-electron Te 0 /Te 4+ conversion in elemental Te, enabling the demonstration of superior Mg//Te dual-ion batteries. Specifically, the classic magnesium aluminum chloride complex (MACC) electrolyte is tailored by introducing Mg bis(trifluoromethanesulfonyl)imide (Mg(TFSI) 2 ), which initiates the Te 0 /Te 4+ conversion with two distinct charge-storage steps. Te cathode undergoes Te/TeCl 4 conversion involving Cl - as charge carriers, during which a tellurium subchloride phase is presented as an intermediate. Significantly, the Te cathode achieves a high specific capacity of 543 mAh g Te and an outstanding energy density of 850 Wh kg -1 , outperforming most of the previously reported cathodes. Our electrolyte analysis indicates that the addition of Mg(TFSI) Te reduces the overall ion-molecule interaction and mitigates the strength of ion-solvent aggregation within the MACC electrolyte, which implies the facilized Cl -1 , outperforming most of the previously reported cathodes. Our electrolyte analysis indicates that the addition of Mg(TFSI) 2 is verified as an essential buffer to mitigate the corrosion and passivation of Mg anodes caused by the consumption of the electrolyte MgCl - in Mg//Te dual-ion cells. These findings provide crucial insights into the development of advanced Mg-based dual-ion batteries.2 is verified as an essential buffer to mitigate the corrosion and passivation of Mg anodes caused by the consumption of the electrolyte MgCl 2 in Mg//Te dual-ion cells. These findings provide crucial insights into the development of advanced Mg-based dual-ion batteries., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Two-dimensional (2D) materials with high chemical stability have attracted intensive interest in membrane design for the separation of organic solvents. As a novel 2D material, polymeric fullerenes (C 60 ) ∞ with distinctive properties are very promising for the development of innovative membranes. In this work, we report the construction of a 2D (C 60 ) ∞ nanosheet membrane for organic solvent separation. The pathways of the (C 60 ) ∞ nanosheet membrane are constructed by sub-1-nm lateral channels and nanoscale in-plane pores created by the depolymerization of the (C 60 ) ∞ nanosheets. Attributing to ordered and shortened transport pathways, the ultrathin porous (C 60 ) ∞ membrane is superior in organic solvent separation. The hexane, acetone, and methanol fluxes are up to 1146.3±53, 900.4±41, and 879.5±42 kg ⋅ m -2  ⋅ h -1 , respectively, which are up to 130 times higher than those of the state-of-the-art membranes with similar dye rejection. Our findings demonstrate the prospect of 2D (C 60 ) ∞ as a promising nanofiltration membrane in the separation of organic solvents from macromolecular compounds such as dyes, drugs, hormones, etc., (© 2024 Wiley‐VCH GmbH.)

Reactions of open-shell molecular graphene fragments are typically thought of as undesired decomposition processes because they lead to the loss of desired features like π-magnetism. Oxidative dimerization of phenalenyl to peropyrene shows, however, that these transformations hold promise as a synthetic tool for making complex structures via formation of multiple bonds and rings in a single step. Here, we explore the feasibility of using this "undesired" reaction of phenalenyl to build up strain and provide access to non-planar polycyclic aromatic hydrocarbons. To this end, we designed and synthesized a biradical system with two phenalenyl units linked via a biphenylene backbone. The design facilitates an intramolecular cascade reaction to a helically twisted saddle-shaped product, where the key transformations-ring-closure and ring-fusion-occur within one reaction. The negative curvature of the final peropyrene product, induced by the formed eight-membered ring, was confirmed by single-crystal X-ray diffraction analysis and the helical twist was validated via resolution of the product's enantiomers that display circularly polarized luminescence and high configurational stability., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The hydrogen molecule, which exists in two spin isomers (ortho- and parahydrogen), is a highly studied system due to its fundamental properties and practical applications. Parahydrogen is used for Nuclear Magnetic Resonance signal enhancement, which is hyperpolarization of other molecules, including biorelevant ones. Hyperpolarization can be achieved by using Signal Amplification by Reversible Exchange (SABRE). SABRE can also convert parahydrogen into orthohydrogen, and surprisingly, in some cases, it has been discovered that orthohydrogen's resonance has the Partially Negative Line (PNL) pattern. Here, an approach for obtaining orthohydrogen with a PNL signal is presented for two catalysts: Ir-IMes, and Ir-IMesBn. The type of solvent in which SABRE is conducted is crucial for the observation of PNL. Specifically, a PNL signal can be easily generated in benzene using both catalysts, but it is more intense for Ir-IMesBn. In acetone, PNL is observed only for Ir-IMesBn. In methanol, no PNL is detected. The PNL effect is only detectable during the initial steps of pre-catalyst activation, and disappears as the activation process progresses. We have proposed a working hypothesis that explains our results. The presented data may facilitate the further investigation of PNL and its applications in material science and catalysis., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Water molecules play an important role in the structure, function, and dynamics of (bio-) materials. A direct access to the number of water molecules in nanoscopic volumes can thus give new molecular insights into materials and allow for fine-tuning their properties in sophisticated applications. The determination of the local water content has become possible by the finding that H 2 O quenches the fluorescence of red-emitting dyes. Since deuterated water, D 2 O, does not induce significant fluorescence quenching, fluorescence lifetime measurements performed in different H 2 O/D 2 O-ratios yield the local water concentration. We combined this effect with the recently developed fluorescence lifetime single molecule localization microscopy imaging (FL-SMLM) in order to nanoscopically determine the local water content in microgels, i.e. soft hydrogel particles consisting of a cross-linked polymer swollen in water. The change in water content of thermo-responsive microgels when changing from their swollen state at room temperature to a collapsed state at elevated temperature could be analyzed. A clear decrease in water content was found that was, to our surprise, rather uniform throughout the entire microgel volume. Only a slightly higher water content around the dye was found in the periphery with respect to the center of the swollen microgels., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The character of the electronic structure of acenes has been the subject of longstanding discussion. However, convincing experimental evidence of their open-shell character has so far been missing. Here, we present the on-surface synthesis of tridecacene molecules by thermal annealing of octahydrotridecacene on a Au(111) surface. We characterized the electronic structure of the tridecacene by scanning probe microscopy, which reveals the presence of an inelastic signal at 126 meV. We attribute the inelastic signal to spin excitation from the singlet diradical ground state to the triplet excited state. To rationalize the experimental findings, we carried out many-body ab initio calculations as well as model Hamiltonians to take into account the effect of the metallic substrate. Moreover, we provide a detailed analysis of how the dynamic electron correlation and virtual charge fluctuation between the molecule and metallic surface reduces the singlet-triplet band gap. Thus, this work provides the first experimental confirmation of the magnetic character of tridecacene., (© 2024 Wiley-VCH GmbH.)

A critical step in photocatalytic water dissociation is the hole-mediated oxidation reaction. Molecular-level insights into the mechanism of this complex reaction under realistic conditions with high temporal resolution are highly desirable. Here, we use femtosecond time-resolved, surface-specific vibrational sum frequency generation spectroscopy to study the photo-induced reaction directly at the interface of the photocatalyst TiO 2 in contact with liquid water at room temperature. Thanks to the inherent surface specificity of the spectroscopic method, we can follow the reaction of solely the interfacial water molecules directly at the interface at timescales on which the reaction takes place. Following the generation of holes at the surface immediately after photoexcitation of the catalyst with UV light, water dissociation occurs on a sub-20 ps timescale. The reaction mechanism is similar at pH 3 and 11. In both cases, we observe the conversion of H 2 O into Ti-OH groups and the deprotonation of pre-existing Ti-OH groups. This study provides unique experimental insights into the early steps of the photo-induced dissociation processes at the photocatalyst-water interface, relevant to the design of improved photocatalysts., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Ruddlesden-Popper-type oxides exhibit remarkable chemical stability in comparison to perovskite oxides. However, they display lower oxygen permeability. We present an approach to overcome this trade-off by leveraging the anisotropic properties of Nd 2 NiO 4+δ . Its (a,b)-plane, having oxygen diffusion coefficient and surface exchange coefficient several orders of magnitude higher than its c-axis, can be aligned perpendicular to the gradient of oxygen partial pressure by a magnetic field (0.81 T). A stable and high oxygen flux of 1.40 mL min -1  cm -2 was achieved for at least 120 h at 1223 K by a textured asymmetric disk membrane with 1.0 mm thickness under the pure CO 2 sweeping. Its excellent operational stability was also verified even at 1023 K in pure CO 2 . These findings highlight the significant enhancement in oxygen permeation membrane performance achievable by adjusting the grain orientation. Consequently, Nd 2 NiO 4+δ emerges as a promising candidate for industrial applications in air separation, syngas production, and CO 2 capture under harsh conditions., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The exceptional thermal stability of diarylethene closed isomers enabled many applications but also prevented utilization in photochromic systems that require rapid thermal reversibility. Herein, we report the diaryltriazolium (DAT + ) photoswitch undergoing thermal cycloreversion within a few milliseconds and absorption of the closed form in the near-infrared region above 900 nm. Click chemistry followed by alkylation offers modular and fast access to the electron-deficient DAT + scaffold. In addition to excellent fatigue resistance, the introduced charge increases water solubility, rendering this photoswitch an ideal candidate for exploring biological applications., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Ion-selective membranes are crucial in various chemical and physiological processes. Numerous studies have demonstrated progress in separating monovalent/multivalent ions, but efficient monovalent/monovalent ion sieving remains a great challenge due to their same valence and similar radii. Here, this work reports a two-dimensional (2D) MXene membrane with super-aligned slit-shaped nanochannels with ultrahigh monovalent ion selectivity. The MXene membrane is prepared by applying shear forces to a liquid-crystalline (LC) MXene dispersion, which is conducive to the highly-ordered stacking of the MXene nanosheets. The obtained LC MXene membrane (LCMM) exhibits ultrahigh selectivities toward Li + /Na + , Li + /K + , and Li + /Rb + separation (≈45, ≈49, and ≈59), combined with a fast Li + transport with a permeation rate of ≈0.35 mol m -2  h -1 , outperforming the state-of-the-art membranes. Theoretical calculations indicate that in MXene nanochannels, the hydrated Li + with a tetrahedral shape has the smallest diameter among the monovalent ions, contributing to the highest mobility. Besides, the weakest interaction is found between hydrated Li + and MXene channels which also contributes to the ultrafast permeation of Li + through the super-aligned MXene channels. This work demonstrates the capability of MXene membranes in monovalent ion separation, which also provides a facile and general strategy to fabricate lamellar membranes in a large scale., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The soaring development of industry exacerbates the shortage of fresh water, making drinking water production an urgent demand. Membrane techniques feature the merits of high efficiency, low energy consumption, and easy operation, deemed as the most potential technology to purify water. Recently, a new type of two-dimensional materials, MXenes as the transition metal carbides or nitrides in the shape of nanosheets, have attracted enormous interest in water purification due to their extraordinary properties such as adjustable hydrophilicity, easy processibility, antifouling resistance, mechanical strength, and light-to-heat transformation capability. In pioneering studies, MXene-based membranes have been evaluated in the past decade for drinking water production including the separation of bacteria, dyes, salts, and heavy metals. This review focuses on the recent advancement of MXene-based membranes for drinking water production. A brief introduction of MXenes is given first, followed by descriptions of their unique properties. Then, the preparation methods of MXene membranes are summarized. The various applications of MXene membranes in water treatment and the corresponding separation mechanisms are discussed in detail. Finally, the challenges and prospects of MXene membranes are presented with the hope to provide insightful guidance on the future design and fabrication of high-performance MXene membranes., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Electrochemical proton storage plays an essential role in designing next-generation high-rate energy storage devices, e.g., aqueous batteries. Two-dimensional conjugated covalent organic frameworks (2D c-COFs) are promising electrode materials, but their competitive proton and metal-ion insertion mechanisms remain elusive, and proton storage in COFs is rarely explored. Here, we report a perinone-based poly(benzimidazobenzophenanthroline) (BBL)-ladder-type 2D c-COF for fast proton storage in both a mild aqueous Zn-ion electrolyte and strong acid. We unveil that the discharged C-O - groups exhibit largely reduced basicity due to the considerable π-delocalization in perinone, thus affording the 2D c-COF a unique affinity for protons with fast kinetics. As a consequence, the 2D c-COF electrode presents an outstanding rate capability of up to 200 A g -1 (over 2500 C), surpassing the state-of-the-art conjugated polymers, COFs, and metal-organic frameworks. Our work reports the first example of pure proton storage among COFs and highlights the great potential of BBL-ladder-type 2D conjugated polymers in future energy devices., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

CuBi 2 O 4 has recently emerged as a promising photocathode for photo-electrochemical (PEC) water splitting. However, its fast degradation under operation currently poses a limit to its application. Here, we report a novel method to study operando the semiconductor-electrolyte interface during PEC operation by surface-sensitive high-energy X-ray scattering. We find that a fast decrease in the generated photocurrents correlates directly with the formation of a metallic Bi phase. We further show that the slower formation of metallic Cu, as well as the dissolution of the electrode in contact with the electrolyte, further affect the CuBi 2 O 4 activity and morphology. Our study provides a comprehensive picture of the degradation mechanisms affecting CuBi 2 O 4 electrodes under operation and poses the methodological basis to investigate the photocorrosion processes affecting a wide range of PEC materials., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Mimicking the structures and functions of cells to create artificial organelles has spurred the development of efficient strategies for production of hollow nanoreactors with biomimetic catalytic functions. However, such structure are challenging to fabricate and are thus rarely reported. We report the design of hollow nanoreactors with hollow multishelled structure (HoMS) and spatially loaded metal nanoparticles. Starting from a molecular-level design strategy, well-defined hollow multishelled structure phenolic resins (HoMS-PR) and carbon (HoMS-C) submicron particles were accurately constructed. HoMS-C serves as an excellent, versatile platform, owing to its tunable properties with tailored functional sites for achieving precise spatial location of metal nanoparticles, internally encapsulated (Pd@HoMS-C) or externally supported (Pd/HoMS-C). Impressively, the combination of the delicate nanoarchitecture and spatially loaded metal nanoparticles endow the pair of nanoreactors with size-shape-selective molecular recognition properties in catalytic semihydrogenation, including high activity and selectivity of Pd@HoMS-C for small aliphatic substrates and Pd/HoMS-C for large aromatic substrates. Theoretical calculations provide insight into the pair of nanoreactors with distinct behaviors due to the differences in energy barrier of substrate adsorption. This work provides guidance on the rational design and accurate construction of hollow nanoreactors with precisely located active sites and a finely modulated microenvironment by mimicking the functions of cells., (© 2023 Wiley-VCH GmbH.)

The regeneration of the reduced form cofactor NAD(P)H is essential for the extra-cellular application of bio-reduction, which necessitates not only the development of efficient artificial NAD(P)H regeneration catalytic system but also its well compatibility with the cascade enzymatic reduction system. In this work, we reported the preparation of a metal nanoparticle (NP) and metal complex integrated core-shell nanoreactor for H 2 -driven NAD(P)H regeneration through the immobilization of a Rh complex on Ni/TiO 2 surface via a bipyridine contained 3D porous organic polymer (POP). In comparison with the corresponding single component metal NPs and the immobilized Rh complex, the integrated catalyst presented simultaneously enhanced activity and selectivity in NAD(P)H regeneration thanks to the rapid spillover of activated H species from metal NPs to Rh complex. In addition, the size-sieving effect of POP precluded the direct interaction of enzyme and Rh complex confined in the pores, enabling the success coupling of core-shell nanoreactor and aldehyde ketone reductase (AKR) for chemoenzymatic reduction of acetophenone to (R)-1-phenylethan-1-ol. This work provides a strategy for the rational manipulation of multicomponent cooperation catalysis., (© 2023 Wiley-VCH GmbH.)

Carbohydrates are the most abundant organic material on Earth and the structural "material of choice" in many living systems. Nevertheless, design and engineering of synthetic carbohydrate materials presently lag behind that for protein and nucleic acids. Bottom-up engineering of carbohydrate materials demands an atomic-level understanding of their molecular structures and interactions in condensed phases. Here, high-resolution scanning tunneling microscopy (STM) is used to visualize at submolecular resolution the three-dimensional structure of cellulose oligomers assembled on Au(1111) and the interactions that drive their assembly. The STM imaging, supported by ab initio calculations, reveals the orientation of all glycosidic bonds and pyranose rings in the oligomers, as well as details of intermolecular interactions between the oligomers. By comparing the assembly of D- and L-oligomers, these interactions are shown to be enantioselective, capable of driving spontaneous enantioseparation of cellulose chains from its unnatural enantiomer and promoting the formation of engineered carbohydrate assemblies in the condensed phases., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The incorporation of nanopores into graphene nanostructures has been demonstrated as an efficient tool in tuning their band gaps and electronic structures. However, precisely embedding the uniform nanopores into graphene nanoribbons (GNRs) at the atomic level remains underdeveloped especially for in-solution synthesis due to the lack of efficient synthetic strategies. Herein we report the first case of solution-synthesized porous GNR (pGNR) with a fully conjugated backbone via the efficient Scholl reaction of tailor-made polyphenylene precursor (P1) bearing pre-installed hexagonal nanopores. The resultant pGNR features periodic subnanometer pores with a uniform diameter of 0.6 nm and an adjacent-pores-distance of 1.7 nm. To solidify our design strategy, two porous model compounds (1 a, 1 b) containing the same pore size as the shortcuts of pGNR, are successfully synthesized. The chemical structure and photophysical properties of pGNR are investigated by various spectroscopic analyses. Notably, the embedded periodic nanopores largely reduce the π-conjugation degree and alleviate the inter-ribbon π-π interactions, compared to the nonporous GNRs with similar widths, affording pGNR with a notably enlarged band gap and enhanced liquid-phase processability., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A new approach towards highly enantioselective halogen-bonding catalysis has been developed. To circumvent the intrinsic issues of the nature of the halogen-bond (XB) and the resultant unresolved limitations in asymmetric catalysis, fine-tuned halogen-halogen interactions between the substrate and XB-donor were designed to preorganize the substrate in the catalyst's cavity and boost enantiocontrol. The present strategy exploits both the electron cloud (Lewis base site) and the sigma (σ)-hole site of the halogen substituent of the substrates to form a tight catalyst-substrate-counteranion chiral complex, thus enabling a controlled induction of high levels of chirality transfer. Remarkable enantioselectivities of up to 95 : 5 e.r. (90 % ee) have been achieved in a model dearomatization reaction of halogen-substituted (iso)quinolines with tetrakis-iodotriazole multidentate anion-binding catalysts., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Fragmentation dynamics of ligated coinage metal clusters reflects their structural and bonding properties. So far methodological challenges limited probing structures of the fragments. Herein, we resolve the geometric structures of the primary fragments of [Ag 29 L 12 ] 3- , i.e. [Ag 24 L 9 ] 2- , [Ag 19 L 6 ] - and [Ag 5 L 3 ] - (L is 1,3-benzene dithiolate). For this, we used trapped ion mobility mass spectrometry to determine collision cross sections of the fragments and compared them to structures calculated by density functional theory. We also report that following two sequential [Ag 5 L 3 ] - elimination steps, further dissociation of [Ag 19 L 6 ] - also involves a new channel of Ag 2 loss and Ag-S and C-S bond cleavages. This reflects a competition between retaining the electronic stability of 8 e - superatom cluster cores and increasing steric strain of ligands and staples. These results are also of potential interest for future soft-landing deposition studies aimed at probing catalytic behavior of Ag clusters on supports., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Two-dimensional van der Waals heterostructures (2D vdWHs) have recently gained widespread attention because of their abundant and exotic properties, which open up many new possibilities for next-generation nanoelectronics. However, practical applications remain challenging due to the lack of high-throughput techniques for fabricating high-quality vdWHs. Here, we demonstrate a general electrochemical strategy to prepare solution-processable high-quality vdWHs, in which electrostatic forces drive the stacking of electrochemically exfoliated individual assemblies with intact structures and clean interfaces into vdWHs with strong interlayer interactions. Thanks to the excellent combination of strong light absorption, interfacial charge transfer, and decent charge transport properties in individual layers, thin-film photodetectors based on graphene/In 2 Se 3 vdWHs exhibit great promise for near-infrared (NIR) photodetection, owing to a high responsivity (267 mA W -1 ), fast rise (72 ms) and decay (426 ms) times under NIR illumination. This approach enables various hybrid systems, including graphene/In 2 Se 3 , graphene/MoS 2 and graphene/MoSe 2 vdWHs, providing a broad avenue for exploring emerging electronic, photonic, and exotic quantum phenomena., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Microwave three-wave mixing has emerged as a novel approach for studying chiral molecules in the gas phase. This technique employs resonant microwave pulses and is a non-linear and coherent approach. It serves as a robust method to differentiate between the enantiomers of chiral molecules and to determine the enantiomeric excess, even in complex chiral mixtures. Besides such analytical applications, the use of tailored microwave pulses allows us to control and manipulate chirality at the molecular level. Here, an overview of some recent developments in the area of microwave three-wave mixing and its extension to enantiomer-selective population transfer is provided. The latter is an important step towards enantiomer separation-in energy and finally in space. In the last section, we present new experimental results on how to improve enantiomer-selective population transfer to achieve an enantiomeric excess of about 40 % in the rotational level of interest using microwave pulses alone., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Plasmon-enhanced electrocatalysis (PEEC), based on a combination of localized surface plasmon resonance excitation and an electrochemical bias applied to a plasmonic material, can result in improved electrical-to-chemical energy conversion compared to conventional electrocatalysis. Here, we demonstrate the advantages of nano-impact single-entity electrochemistry (SEE) for investigating the intrinsic activity of plasmonic catalysts at the single-particle level using glucose electrooxidation and oxygen reduction on gold nanoparticles as model reactions. We show that in conventional ensemble measurements, plasmonic effects have minimal impact on photocurrents. We suggest that this is due to the continuous equilibration of the Fermi level (E F ) of the deposited gold nanoparticles with the E F of the working electrode, leading to fast neutralization of hot carriers by the measuring circuit. The photocurrents detected in the ensemble measurements are primarily caused by photo-induced heating of the supporting electrode material. In SEE, the E F of suspended gold nanoparticles is unaffected by the working electrode potential. As a result, plasmonic effects are the dominant source of photocurrents under SEE experimental conditions., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The formation of an appropriate solid electrolyte interphase (SEI) at the anode of a sodium battery is crucially dependent on the electrochemical stability of solvent and electrolyte at the redox potential of Na/Na + in the respective system. In order to determine entropic contributions to the relative stability of the electrolyte solution, we measure the reaction entropy of Na metal deposition for diglyme (DG) and propylene carbonate (PC) based electrolyte solutions by electrochemical microcalorimetry at single electrodes. We found a large positive reaction entropy for Na + deposition in DG of Δ R S DG ≈ ${S\left({\rm { DG}}\right)\approx \ }$ 234 J mol -1  K -1 (c.f.: Δ R S PC ≈ ${S\left({\rm { PC}}\right)\approx \ }$ 83 J mol -1  K -1 ), which signals substantial entropic destabilization of Na + in DG by about 0.73 eV, thus increasing the stability of solvent and electrolyte relative to Na + reduction. We attribute this strong entropic destabilization to a highly negative solvation entropy of Na + , due to the low dielectric constant and high freezing entropy of DG., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

As alternative energy sources are essential to reach a climate-neutral economy, hydrogen peroxide (H 2 O 2 ) as futuristic energy carrier gains enormous awareness. However, seeking for stable and electrochemically selective H 2 O 2 ORR electrocatalyst is yet a challenge, making the design of-ideally-bifunctional catalysts extremely important and outmost of interest. In this study, we explore the application of a trimetallic cobalt(II) triazole pyridine bis-[cobalt(III) corrole] complex Co II TP[Co III C] 2 3 in OER and ORR catalysis due to its remarkable physicochemical properties, fast charge transfer kinetics, electrochemical reversibility, and durability. With nearly 100 % selective catalytic activity towards the two-electron transfer generated H 2 O 2 , an ORR onset potential of 0.8 V vs RHE and a cycling stability of 50 000 cycles are detected. Similarly, promising results are obtained when applied in OER catalysis. A relatively low overpotential at 10 mA cm -2 of 412 mV, Faraday efficiency 98 % for oxygen, an outstanding Tafel slope of 64 mV dec -1 combined with superior stability., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Graphdiynes (GDYs), two-dimensional graphene-like carbon systems, are considered as potential advanced membrane material due to their unique physicochemical features. Nevertheless, the scale-up of integrated GDY membranes is technologically challenging, and most studies remain at the theoretical stage. Herein, we report a simple and efficient alkynylated surface-mediated strategy to prepare hydrogen-substituted graphdiyne (HsGDY) membranes on commercial alumina tubes. Surface alkynylation initiates an accelerated surface-confined coupling reaction in the presence of a copper catalyst and facilitates the nanoscale epitaxial lateral growth of HsGDY. A continuous and ultra-thin HsGDY membrane (∼100 nm) can be produced within 15 min. The resulting membranes exhibit outstanding molecular sieving together with excellent water permeances (ca. 1100 L m -2  h -1 MPa -1 ), and show a long-term durability in cross-flow nanofiltration, owing to the superhydrophilic surface and hydrophobic pore walls., (© 2023 Wiley-VCH GmbH.)

This study employs TLD1433, a Ru II -based photodynamic therapy (PDT) agent in human clinical trials, as a benchmark to establish protocols for studying the excited-state dynamics of photosensitizers (PSs) in cellulo, in the local environment provided by human cancer cells. Very little is known about the excited-state properties of any PS in live cells, and for TLD1433, it is terra incognita. This contribution targets a general problem in phototherapy, which is how to interrogate the light-triggered, function-determining processes of the PSs in the relevant biological environment, and establishes methodological advances to study the ultrafast photoinduced processes for TLD1433 when taken up by MCF7 cells. We generalize the methodological developments and results in terms of molecular physics by applying them to TLD1433's analogue TLD1633, making this study a benchmark to investigate the excited-state dynamics of phototoxic compounds in the complex biological environment., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Azeotropic organic solvent mixture separation is common in the chemical industry but extremely difficult. Zeolitic imidazolate framework-67 (ZIF-67) shows great potential in organic solvent mixture separation due to its rigid micropores and excellent stability. However, due to the fast nucleation rate, it is a great challenge to prepare continuous ZIF-67 membrane layers with ultrathin thickness. In this study, a hydroxy salt layer with high inducible activity was synthesized as a precursor on different porous substrates to prepare ZIF-67 membranes at room temperature. The precursor layer enables an intact ZIF-67 membrane with an ultrathin thickness of 176±12 nm. The experimental and simulation results confirmed that the size sieving through the pore windows and the preferential adsorption of polar solvent molecules provide the ZIF-67 membrane an unprecedented separation performance such as high separation factors and fluxes, for four types of azeotropic organic solvent mixtures., (© 2023 Wiley-VCH GmbH.)

Organic/inorganic interfaces greatly affect Li + transport in composite solid electrolytes (SEs), while SE/electrode interfacial stability plays a critical role in the cycling performance of solid-state batteries (SSBs). However, incomplete understanding of interfacial (in)stability hinders the practical application of composite SEs in SSBs. Herein, chemical degradation between Li 6 PS 5 Cl (LPSCl) and poly(ethylene glycol) (PEG) is revealed. The high polarity of PEG changes the electronic state and structural bonding of the PS 4 tetrahedra, thus triggering a series of side reactions. A substituted terminal group of PEG not only stabilizes the inner interfaces but also extends the electrochemical window of the composite SE. Moreover, a LiF-rich layer can effectively prevent side reactions at the Li/SE interface. The results provide insights into the chemical stability of polymer/sulfide composites and demonstrate an interface design to achieve dendrite-free lithium metal batteries.3- tetrahedra, thus triggering a series of side reactions. A substituted terminal group of PEG not only stabilizes the inner interfaces but also extends the electrochemical window of the composite SE. Moreover, a LiF-rich layer can effectively prevent side reactions at the Li/SE interface. The results provide insights into the chemical stability of polymer/sulfide composites and demonstrate an interface design to achieve dendrite-free lithium metal batteries., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The unique structural characteristics of three-dimensional (3D) covalent organic frameworks (COFs) like high surface areas, interconnected pore system and readily accessible active sites render them promising platforms for a wide set of functional applications. Albeit promising, the reticular construction of 3D COFs with large pores is a very demanding task owing to the formation of interpenetrated frameworks. Herein we report the designed synthesis of a 3D non-interpenetrated stp net COF, namely TUS-64, with the largest pore size of all 3D COFs (47 Å) and record-low density (0.106 g cm -3 ) by reticulating a 6-connected triptycene-based linker with a 4-connected porphyrin-based linker. Characterized with a highly interconnected mesoporous scaffold and good stability, TUS-64 shows efficient drug loading and controlled release for five different drugs in simulated body fluid environment, demonstrating the competency of TUS-64 as drug nanocarriers., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Solid-state batteries (SSBs) with high-voltage cathode active materials (CAMs) such as LiNi 1-x-y Co x Mn y O 2 (NCM) and poly(ethylene oxide) (PEO) suffer from "noisy voltage" related cell failure. Moreover, reports on their long-term cycling performance with high-voltage CAMs are not consistent. In this work, we verified that the penetration of lithium dendrites through the solid polymer electrolyte (SPE) indeed causes such "noisy voltage cell failure". This problem can be overcome by a simple modification of the SPE using higher molecular weight PEO, resulting in an improved cycling stability compared to lower molecular weight PEO. Furthermore, X-ray photoelectron spectroscopy analysis confirms the formation of oxidative degradation products after cycling with NCM, for what Fourier transform infrared spectroscopy is not suitable as an analytical technique due to its limited surface sensitivity. Overall, our results help to critically evaluate and improve the stability of PEO-based SSBs., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The hydroxylation of fatty acids is an appealing reaction in synthetic chemistry, although the lack of selective catalysts hampers its industrial implementation. In this study, we have engineered a highly regioselective fungal peroxygenase for the ω-1 hydroxylation of fatty acids with quenched stepwise over-oxidation. One single mutation near the Phe catalytic tripod narrowed the heme cavity, promoting a dramatic shift toward subterminal hydroxylation with a drop in the over-oxidation activity. While crystallographic soaking experiments and molecular dynamic simulations shed light on this unique oxidation pattern, the selective biocatalyst was produced by Pichia pastoris at 0.4 g L -1 in a fed-batch bioreactor and used in the preparative synthesis of 1.4 g of (ω-1)-hydroxytetradecanoic acid with 95 % regioselectivity and 83 % ee for the S enantiomer., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)