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A negatively curved aza‐nanographene (NG) containing two octagons was synthesized by a regioselective and stepwise cyclodehydrogenation procedure, in which a double aza[7]helicene was simultaneously formed as an intermediate. Their saddle‐shaped structures with negative curvature were unambiguously confirmed by X‐ray crystallography, thereby enabling the exploration of the structure–property relationship by photophysical, electrochemical and conformational studies. Moreover, the assembly of the octagon‐embedded aza‐NG with fullerenes was probed by fluorescence spectral titration, with record‐high binding constants (Ka=9.5×103 M−1 with C60, Ka=3.7×104 M−1 with C70) found among reported negatively curved polycyclic aromatic compounds. The tight association of aza‐NG with C60 was further elucidated by X‐ray diffraction analysis of their co‐crystal, which showed the formation of a 1 : 1 complex with substantial concave‐convex interactions. [ABSTRACT FROM AUTHOR]

Tautomers coexisting in an equilibrium system have significant potential for regulating luminescent properties because of their structural differences. However, separating and stabilizing tautomers at room temperature is a considerable challenge. In this study, it is found that hydrogen‐bonded organic frameworks (HOFs) composed of Br‐ anions can effectively separate and stabilize two proton‐transfer tautomers of triarylformamidinium bromide: namely, the nitrogen cation (BA‐N) and carbon cation (BA‐C). The BA‐N crystal consisting of a dense anionic HOF and parallelly aligned organic cations exhibits green thermally activated delayed fluorescence and red room‐temperature phosphorescence (RTP). The BA‐C crystal contains acetone molecules that induce an antiparallel arrangement of the organic cations to form a loose HOF, producing blue prompt fluorescence and green RTP. Interestingly, switching of the HOFs between BA‐N and BA‐C can be achieved through the uptake and release of acetone, thereby dynamically adjusting multiple luminescent properties. Consequently, the HOF crystals can be used for the highly sensitive and specific sensing of acetone with a detection limit of 66.74 ppm. This study not only stabilizes tautomeric luminescent materials at room temperature, but also provides a new method for constructing smart HOFs with a sensitive response to a stimulus. [ABSTRACT FROM AUTHOR]

Ionische Flüssigkeiten (ionic liquids, ILs) eingebettet in feste Polymer‐Elektrolyte (iono‐SPEs) weisen eine hohe ionische Leitfähigkeit auf, zeigen jedoch einen nicht‐uniformen Li+‐Transport in den verschiedenen Phasen. In dieser Arbeit wird gezeigt wie der Li+‐Transport in Polymerphasen erheblich durch ein Poly(vinylidenfluorid‐trifluorethylen‐chlorotrifluorethylen)‐Netzwerk [P(VDF‐TrFE‐CTFE), PTC] ILs zur Herstellung von iono‐SPEs verbessert werden kann. Im Gegensatz zu PVDF zeigt PTC mit geeigneter Polarität eine schwächere Adsorptionsenergie an IL‐Kationen, wodurch ihre Möglichkeit, Li+‐Sprungstellen zu besetzen, reduziert wird. Die deutlich höhere Dielektrizitätskonstante von PTC als PVDF erleichtert die Dissoziation von Li‐Anionen‐Clustern. Diese beiden Faktoren verstärken den Li+‐Transport entlang von PTC‐Ketten, wodurch der Unterschied des Li+‐Transports zwischen den verschiedenen Phasen verringert wird. Die LiFePO4/PTC iono‐SPE/Li‐Zellenzyklen stabil mit einer Kapazitätserhaltung von 91.5 % nach 1000 Zyklen bei 1 C und 25 °C. Diese Arbeit ebnet einen neuen Weg zur Erzeugung eines gleichmäßigen Li+‐Flusses in iono‐SPEs durch Optimierung der Polarität und Dielektrizität der Polymermatrix. [ABSTRACT FROM AUTHOR]

Since the breakthrough of conductive polymers in 1977, scientists have made great efforts to create small band gap (Eg) conjugated polymers. Two general strategies to design small Eg conjugated polymers are quinoid structure and donor‐acceptor structure. Ultrasmall Eg conjugated polymers (Eg<1.0 eV) always suffer from poor air stability because of high‐lying HOMO energy levels. In this work, we report a new strategy to design ultrasmall Eg conjugated polymers by N−B←N unit, i.e. balanced resonant boron‐nitrogen covalent bond (B−N) and boron‐nitrogen coordination bond (B←N). The resulting polymer exhibits an Eg of 0.82 eV and an onset absorption wavelength of >1500 nm. Moreover, the polymer exhibits excellent air stability because of its low‐lying LUMO/HOMO energy levels. An unprecedented property of this polymer is the selective light absorption in the infrared range (800–1500 nm) and high transparency in the visible range (400–780 nm). Using this property, for the first time, we demonstrate the application of conjugated polymers as transparent thermal‐shielding coating layer on glass, which reduces indoor solar irradiation through window and consequently reduces power consumption for cooling of buildings and cars in summer. [ABSTRACT FROM AUTHOR]

As a green route for large‐scale energy storage, aqueous organic redox flow batteries (AORFBs) are attracting extensive attention. However, most of the reported AORFBs were operated in an inert atmosphere. Herein, we clarify this issue by using the reported AORFB (i.e. 3, 3′‐(9,10‐anthraquinone‐diyl)bis(3‐methylbutanoicacid) (DPivOHAQ)||Ferrocyanide) as an example. We demonstrate that the dissolved O2 can oxidize the discharged DPivOHAQ in anolyte, leading to capacity‐imbalance between anolyte and catholyte. Therefore, this cell shows continuous capacity fading when operated in an air atmosphere. We propose a simple strategy for this challenge, in which the oxygen evolution reaction (OER) in catholyte is employed to balance oxygen reduction reaction (ORR) in anolyte. When using the Ni(OH)2‐modifed carbon felt (CF) as a current collector for catholyte, this cell shows an excellent stability in air atmosphere because the Ni(OH)2‐induced OER capacity in catholyte exactly balances the ORR capacity in anolyte. Such O2‐balance strategy facilitates AORFBs' practical application. [ABSTRACT FROM AUTHOR]

The asymmetric synthesis of 2,2‐difluorinated tetrahydrofurans was accomplished via enantioselective formal [3+2] cycloaddition catalyzed by palladium. The asymmetric reaction between gem‐difluoroalkenes and racemic vinyl epoxides or vinylethylene carbonates resulted in the formation of enantioenriched 2,2‐difluorotetrahydrofurans with an enantioselectivity up to 98 %. Notably, the reaction used the readily available (R)‐BINAP as the ligand at a low loading and yielded a wide variety of difluorinated products in moderate to high yields. Both chiral diastereomers could be obtained in a single sequence. [ABSTRACT FROM AUTHOR]

Silicon‐mediated fluoride abstraction is demonstrated as a means of generating the first fluorido‐cyanido transition metal complexes. This new synthetic approach is exemplified by the synthesis and characterization of the heteroleptic complexes, trans‐[MIVF4(CN)2]2− (M=Re, Os), obtained from their homoleptic [MIVF6]2− parents. As shown by combined high‐field electron paramagnetic resonance spectroscopy and magnetization measurements, the partial substitution of fluoride by cyanide ligands leads to a marked increase in the magnetic anisotropy of trans‐[ReF4(CN)2]2− as compared to [ReF6]2−, reflecting the severe departure from an ideal octahedral (Oh point group) ligand field. This methodology paves the way toward the realization of new heteroleptic transition metal complexes that may be used as highly anisotropic building‐blocks for the design of high‐performance molecule‐based magnetic materials. [ABSTRACT FROM AUTHOR]

Molecular ferroelectrics have attracted considerable interests because of their easy and environmentally friendly processing, low acoustical impedance and mechanical flexibility. Herein, a molecular thermochromic ferroelectric, N,N′‐dimethyl‐1,4‐diazoniabicyclo[2.2.2]octonium tetrachlorocuprate(II) ([DMe‐DABCO]CuCl4) is reported, which shows both excellent ferroelectricity and intriguing thermochromism. [DMe‐DABCO]CuCl4 undergoes a ferroelectric phase transition from Pca21 to Pbcm at a significantly high Curie temperature of 413 K, accompanied by a color change from yellow to red that is due to the remarkable deformation of [CuCl4]2− tetrahedron, where the ferroelectric and paraelectric phases correspond to yellow and red, respectively. Combined with multiple bistable physical properties, [DMe‐DABCO]CuCl4 would be a promising candidate for next‐generation smart devices, and should inspire further exploration of multifunctional molecular ferroelectrics. [ABSTRACT FROM AUTHOR]

Small‐molecule crosslinkers are invaluable for probing biomolecular interactions and for crosslinking mass spectrometry. Existing chemical crosslinkers target only a small selection of amino acids, while conventional photo‐crosslinkers target almost all residues non‐specifically, complicating data analysis. Herein, we report photocaged quinone methide (PQM)‐based crosslinkers that target nine nucleophilic residues through Michael addition, including Gln, Arg, and Asn, which are inaccessible to existing chemical crosslinkers. PQM crosslinkers were used in vitro, in Escherichia coli, and in mammalian cells to crosslink dimeric proteins and endogenous membrane receptors. The heterobifunctional crosslinker NHQM could crosslink proteins to DNA, for which few crosslinkers exist. The photoactivatable reactivity of these crosslinkers and their ability to target multiple amino acids will enhance the use of chemical crosslinking for studies of protein–protein and protein–DNA networks and for structural biology. [ABSTRACT FROM AUTHOR]

Due to their limited capacity for π‐backdonation, isolation of π‐complexes of main‐group elements remains a great challenge. We report herein the synthesis of a homoleptic diphosphene lead complex (2) from the degradation of P4 with a bis(germylene)‐stabilized Pb(0) complex. Structural and computational studies showed that 2 possesses significant π bonding interactions between Pb atom and diphosphene ligands, which is reminiscent of transition‐metal diphosphene complexes. Consistent with its unique electronic structure, complex 2 can deliver Pb(0) atoms to perform redox reaction with an iminoquinone to produce a cyclic plumbylene (4) and perform 2,5‐dimethyl‐3,4‐dimethylimidazol‐1‐ylidene (IMe2Me2) induced phosphorus cation abstraction to give an anionic PbP3 complex (6). [ABSTRACT FROM AUTHOR]

Two pure silver nanoparticles (Ag210(iPrPhS)71(Ph3P)5Cl and Ag211(iPrPhS)71(Ph3P)6Cl labeled as SD/Ag210 and SD/Ag211 (SD=SunDi), were found to co‐crystallize in forming compound 1. Single‐crystal X‐ray diffraction (SCXRD) revealed that they differ by only one Ag(PPh3). Their four‐shell nanoparticles consist of three pure Ag metal shells (Ag19@Ag52@Ag45) shielded by a silver‐organic Ag89(iPrPhS)71Cl[Ag(Ph3P)]n outermost shell. The number (n) of Ag(Ph3P) is five for SD/Ag210 and six for SD/Ag211. The pseudo‐fivefold symmetric Ag nanoparticles exhibit surface plasmon absorption similar to a true metallic state but at the nanoscale. This work exemplifies the important effects of phosphine in stabilizing large silver nanoparticles; and offers a platform to investigate the origin of differences in nanoscale metal materials, even differing by only one metal atom; it also sheds light on the regioselective binding of auxiliary Ph3P on the surface of silver nanoparticles. [ABSTRACT FROM AUTHOR]

Analogous to reversible post‐translational protein modifications, the ability to attach and subsequently remove modifications on proteins would be valuable for protein and biological research. Although bioorthogonal functionalities have been developed to conjugate or cleave protein modifications, they are introduced into proteins on separate residues and often with bulky side chains, limiting their use to one type of control and primarily protein surface. Here we achieved dual control on one residue by genetically encoding S‐propargyl‐cysteine (SprC), which has bioorthogonal alkyne and propargyl groups in a compact structure, permitting usage in protein interior in addition to surface. We demonstrated its incorporation at the dimer interface of glutathione transferase for in vivo crosslinking via thiol–yne click chemistry, and at the active site of human rhinovirus 3C protease for masking and then turning on enzyme activity via Pd‐cleavage of SprC into Cys. In addition, we installed biotin onto EGFP via Sonogashira coupling of SprC and then tracelessly removed it via Pd cleavage. SprC is small in size, commercially available, nontoxic, and allows for bond building and breaking on a single residue. Genetically encoded SprC will be valuable for chemically controlling proteins with an essential Cys and for reversible protein modifications. [ABSTRACT FROM AUTHOR]

Organic molecules with near‐infrared II (NIR II) light absorption are essential for many biological and opto‐electronic applications. Herein, we report monodispersed oligomers as NIR II light absorber using a new molecular design strategy of resonant N−B←N unit, i.e. balanced resonant boron‐nitrogen covalent bond (B−N) and boron‐nitrogen coordination bond (B←N). We synthesize a series of monodispersed oligomers with thiophene‐fused 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (TB), which contains resonant N−B←N unit, as the repeating unit. The TB pentamer exhibits the maximum absorption wavelength of 1169 nm, which is the longest for oligomers reported so far. Organic photodetectors (OPDs) with the TB tetramer as the electron acceptor shows the specific detectivity of 2.98×1011 Jones at 1180 nm under zero bias. This performance is among the best for NIR II OPDs. These results indicate a new kind of NIR II absorbing molecules as excellent opto‐electronic materials. [ABSTRACT FROM AUTHOR]

An extremely rare non-Kramers holmium(III) single-ion magnet (SIM) is reported to be stabilized in the pentagonal-bipyramidal geometry by a phosphine oxide with a high energy barrier of 237(4) cm−1. The suppression of the quantum tunneling of magnetization (QTM) at zero field and the hyperfine structures originating from field-induced QTMs can be observed even from the field-dependent alternating-current magnetic susceptibility in addition to single-crystal hysteresis loops. These dramatic dynamics were attributed to the combination of the favorable crystal-field environment and the hyperfine interactions arising from 165Ho ( I=7/2) with a natural abundance of 100 %. [ABSTRACT FROM AUTHOR]

Double helicenes are appealing chiral frameworks. Their π‐extension is desirable to achieve (chir)optical response in the visible and near‐infrared (NIR) region, but access to higher double [n]helicenes (n≥8) has remained challenging. Herein, we report an unprecedented π‐extended double [9]helicene (D9H), unambiguously revealing its structure by single‐crystal X‐ray diffraction. D9H shows remarkable NIR emission from 750 to 1100 nm with a high photoluminescence quantum yield of 18 %. In addition, optically pure D9H exhibits panchromatic circular dichroism with a notable dissymmetry factor (gCD) of 0.019 at 590 nm, which is among the highest in the visible region for reported helicenes. [ABSTRACT FROM AUTHOR]

Silicon is an attractive anode material in energy storage devices, as it has a ten times higher theoretical capacity than its state-of-art carbonaceous counterpart. However, the common process to synthesize silicon nanostructured electrodes is complex, costly, and energy-intensive. Three-dimensional (3D) porous silicon-based anode materials have been fabricated from natural reed leaves by calcination and magnesiothermic reduction. This sustainable and highly abundant silica source allows for facile production of 3D porous silicon with very good electrochemical performance. The obtained silicon anode retains the 3D hierarchical architecture of the reed leaf. Impurity leaching and gas release during the fabrication process leads to an interconnected porosity and the reductive treatment to an inside carbon coating. Such anodes show a remarkable Li-ion storage performance: even after 4000 cycles and at a rate of 10 C, a specific capacity of 420 mA h g−1 is achieved. [ABSTRACT FROM AUTHOR]

The first cross-coupling reaction between aryl silanes and aryl boronic acids is described. This transformation represents one of the very few examples of coupling reactions between two nucleophilic organometallic reagents and provides a new method for the formation of biaryl compounds. The successful development of this reaction was enabled by the use of commercially available 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) as the ligand. A small amount of BINAP (3 mol %) was sufficient to suppress the formation of the homocoupling products, and the reaction yielded the cross-coupling products with high selectivity under mild conditions, even when the ratio of the two coupling partners was 1:1. [ABSTRACT FROM AUTHOR]

Eine Rekord-Anisotropiebarriere (319 cm−1) unter sämtlichen d-f-Komplexen wurde für einen einzigartigen FeII-DyIII-FeII-Einzelmolekülmagneten (single molecule magnet, SMM) gefunden, der zwei asymmetrische und verzerrte FeII-Ionen und ein quasi- D5 h-symmetrisches DyIII-Ion enthält. Die eingefrorene Magnetisierung der DyIII-Ionen führt zur verlangsamten Relaxation der FeII-Ionen, die im Mößbauer-Spektrum beobachtet wird. Ab-initio-Rechnungen legen nahe, dass ein Tunneln durch Austauschdubletts erfolgreich unterbrochen wird. [ABSTRACT FROM AUTHOR]

The alkaline oxygen evolution reaction (OER) is a promising avenue for producing clean fuels and storing intermittent energy. However, challenges such as excessive OH− consumption and strong adsorption of oxygen‐containing intermediates hinder the development of alkaline OER. In this study, we propose a cooperative strategy by leveraging both nano‐scale and atomically local electric fields for alkaline OER, demonstrated through the synthesis of Mn single atom doped CoP nanoneedles (Mn SA‐CoP NNs). Finite element method simulations and density functional theory calculations predict that the nano‐scale local electric field enriches OH− around the catalyst surface, while the atomically local electric field improves *O desorption. Experimental validation using in situ attenuated total reflection infrared and Raman spectroscopy confirms the effectiveness of the nano‐scale and atomically electric fields. Mn SA‐CoP NNs exhibit an ultra‐low overpotential of 189 mV at 10 mA cm−2 and stable operation over 100 hours at ~100 mA cm−2 during alkaline OER. This innovative strategy provides new insights for enhancing catalyst performance in energy conversion reactions. [ABSTRACT FROM AUTHOR]

The generation of solid electrolyte interphase (SEI) largely determines the comprehensive performance of all‐solid‐state batteries. Herein, a novel "carrier‐catalytic" integrated design is strategically exploited to in situ construct a stable LiF‐LiBr rich SEI by improving the electron transfer kinetics to accelerate the bond‐breaking dynamics. Specifically, the high electron transport capacity of Br‐TPOM skeleton increases the polarity of C−Br, thus promoting the generation of LiBr. Then, the enhancement of electron transfer kinetics further promotes the fracture of C−F from TFSI− to form LiF. Finally, the stable and homogeneous artificial‐SEI with enriched lithium dihalide is constructed through the in situ co‐growth mechanism of LiF and LiBr, which facilitatse the Li‐ion transport kinetics and regulates the lithium deposition behavior. Impressively, the PEO‐Br‐TPOM paired with LiFePO4 delivers ultra‐long cycling stability over 1000 cycles with 81 % capacity retention at 1 C while the pouch cells possess 88 % superior capacity retention after 550 cycles with initial discharge capacity of 145 mAh g−1at 0.2 C in the absence of external pressure. Even under stringent conditions, the practical pouch cells possess the practical capacity with stable electric quantities plateau in 30 cycles demonstrates its application potential in energy storage field. [ABSTRACT FROM AUTHOR]

Recent biochemical results suggest that auxin (IAA) efflux is mediated by a vesicular cycling mechanism, but no direct detection of vesicular IAA release from single plant cells in real-time has been possible up to now. A TiC@C/Pt-QANFA micro-electrochemical sensor has been developed with high sensitivity in detection of IAA, and it allows real-time monitoring and quantification of the quantal release of auxin from single plant protoplast by exocytosis. [ABSTRACT FROM AUTHOR]

We herein report an organoboron compound (SBN‐1) based on N−B←N units with a balanced resonance hybrid of B, N single bond (B−N) and B, N coordination bond (B←N). Despite the different chemical environments of the two nitrogen atoms in the N−B←N unit, the single‐crystal structure reveals that the two B, N bonds have similar bond lengths of ca. 1.55 Å and are almost equivalent. The resonance nature of the two B, N bonds contributes to the excellent chemical stability and photostability of SBN‐1. The N−B←N units in SBN‐1 show a strong electron‐withdrawing capability and large dipole, resulting in a red‐shifted absorption spectrum, downshifted LUMO/HOMO energy levels, and drastically altered molecular packing behaviors in solid state. SBN‐1 can be used as a building block to construct small band gap conjugated polymers. The resonance of B, N bonds discovered in this work provides new insight into the design of stable organoboron small molecules and polymers for practical applications. [ABSTRACT FROM AUTHOR]

The solid‐state electrolyte interface (SEI) between the solid‐state polymer electrolyte and the lithium metal anode dramatically affects the overall battery performance. Increasing the content of lithium fluoride (LiF) in SEI can help the uniform deposition of lithium and inhibit the growth of lithium dendrites, thus improving the cycle stability performance of lithium batteries. Currently, most methods of constructing LiF SEI involve decomposing the lithium salt by the polar groups of the filler. However, there is a lack of research reports on how to affect the SEI layer of Li‐ion batteries by increasing the charge transfer number. In this study, a porous organic polymer with "charge storage" properties was prepared and doped into a polymer composite solid electrolyte to study the effect of sufficient charge transfer on the decomposition of lithium salts. The results show in contrast to porphyrins, the unique structure of POF allows for charge transfer between each individual porphyrin. Therefore, during TFSI− decomposition to the formation of LiF, TFSI− can obtain sufficient charge, thereby promoting the break of C−F and forming the LiF‐rich SEI. Compared with single porphyrin (0.423 e−), POF provides 2.7 times more charge transfer to LiTFSI (1.147 e−). The experimental results show that Li//Li symmetric batteries equipped with PEO‐POF can be operated stably for more than 2700 h at 60 °C. Even the Li//Li (45 μm) symmetric cells are stable for more than 1100 h at 0.1 mA cm−1. In addition, LiFePO4//PEO‐POF//Li batteries have excellent cycling performance at 2 C (80 % capacity retention after 750 cycles). Even LiFePO4//PEO‐POF//Li (45 μm) cells have excellent cycling performance at 1 C (96 % capacity retention after 300 cycles). Even when the PEO‐base is replaced with a PEG‐base and a PVDF‐base, the performance of the cell is still significantly improved. Therefore, we believe that the concept of charge transfer offers a novel perspective for the preparation of high‐performance assemblies. [ABSTRACT FROM AUTHOR]

The deployment of lithium metal anode in solid‐state batteries with polymer electrolytes has been recognized as a promising approach to achieving high‐energy‐density technologies. However, the practical application of the polymer electrolytes is currently constrained by various challenges, including low ionic conductivity, inadequate electrochemical window, and poor interface stability. To address these issues, a novel eutectic‐based polymer electrolyte consisting of succinonitrile (SN) and poly (ethylene glycol) methyl ether acrylate (PEGMEA) is developed. The research results demonstrate that the interactions between SN and PEGMEA promote the dissociation of the lithium difluoro(oxalato) borate (LiDFOB) salt and increase the concentration of free Li+. The well‐designed eutectic‐based PAN1.2‐SPE (PEGMEA: SN=1: 1.2 mass ratio) exhibits high ionic conductivity of 1.30 mS cm−1 at 30 °C and superior interface stability with Li anode. The Li/Li symmetric cell based on PAN1.2‐SPE enables long‐term plating/stripping at 0.3 and 0.5 mA cm−2, and the Li/LiFePO4 cell achieves superior long‐term cycling stability (capacity retention of 80.3 % after 1500 cycles). Moreover, Li/LiFePO4 and Li/LiNi0.6Co0.2Mn0.2O2 pouch cells employing PAN1.2‐SPE demonstrate excellent cycling and safety characteristics. This study presents a new pathway for designing high‐performance polymer electrolytes and promotes the practical application of high‐stable lithium metal batteries. [ABSTRACT FROM AUTHOR]

Lithium fluoride (LiF) at the solid electrolyte interface (SEI) contributes to the stable operation of polymer‐based solid‐state lithium metal batteries. Currently, most of the methods for constructing lithium fluoride SEI are based on the design of polar groups of fillers. However, the mechanism behind how steric hindrance of fillers impacts LiF formation remains unclear. This study synthesizes three kinds of porous polyacetal amides (PAN‐X, X=NH2, NH‐CH3, N‐(CH3)2) with varying steric hindrances by regulating the number of methyl substitutions of nitrogen atoms on the reaction monomer, which are incorporated into polymer composite solid electrolytes, to investigate the regulation mechanism of steric hindrance on the content of lithium fluoride in SEI. The results show that bis(trifluoromethanesulfonyl)imide (TFSI−) will compete for the charge without steric effect, while excessive steric hindrance hinders the interaction between TFSI− and polar groups, reducing charge acquisition. Only when one hydrogen atom on the amino group is replaced by a methyl group, steric hindrance from the methyl group prevents TFSI− from capturing charge in that direction, thereby facilitating the transfer of charge from the polar group to a separate TFSI− and promoting maximum LiF formation. This work provides a novel perspective on constructing LiF‐rich SEI. [ABSTRACT FROM AUTHOR]

3D‐MoS2 can adsorb organic molecules and provide multidimensional electron transport pathways, implying a potential application for environment remediation. Here, we study the degradation of aromatic organics in advanced oxidation processes (AOPs) by a 3D‐MoS2 sponge loaded with MoS2 nanospheres and graphene oxide (GO). Exposed Mo4+ active sites on 3D‐MoS2 can significantly improve the concentration and stability of Fe2+ in AOPs and keep the Fe3+/Fe2+ in a stable dynamic cycle, thus effectively promoting the activation of H2O2/peroxymonosulfate (PMS). The degradation rate of organic pollutants in the 3D‐MoS2 system is about 50 times higher than without cocatalyst. After a 140 L pilot‐scale experiment, it still maintains high efficiency and stable AOPs activity. After 16 days of continuous reaction, the 3D‐MoS2 achieves a degradation rate of 120 mg L−1 antibiotic wastewater up to 97.87 %. The operating cost of treating a ton of wastewater is only US$ 0.33, suggesting huge industrial applications. [ABSTRACT FROM AUTHOR]

N2O5 is an important intermediate in the atmospheric nitrogen cycle. Using a flow tube reactor, N2O5 was found to be released from the TiO2 surface during the photocatalytic oxidation of NO2, revealing a previously unreported source of N2O5. The rate of N2O5 release from TiO2 was dependent on the initial NO2 concentration, relative humidity, O2/N2 ratio, and irradiation intensity. Experimental evidence and quantum chemical calculations showed that NO2 can react with the surface hydroxyl groups and the generated electron holes on the TiO2, followed by combining with another NO2 molecule to form N2O5. The latter was physisorbed on TiO2 and had a low adsorption energy of −0.13 eV. Box model simulations indicated that the new source of N2O5 released from TiO2 can increase the daytime N2O5 concentration by up to 20 % in urban areas if abundant TiO2‐containing materials and high NOx concentrations were present. This joint experimental/theoretical study not only demonstrates a new chemical mechanism for N2O5 formation but also has important implications for air quality in urban areas. [ABSTRACT FROM AUTHOR]

Synthesis of highly stable two‐dimensional single‐layer assemblies (SLAs) is a key challenge in supramolecular science, especially those with long‐range molecular order and well‐defined morphology. Here, thin (thickness <2 nm) triangular AuI‐thiolate SLAs with high thermo‐, solvato‐ and mechano‐ stability have been synthesized via a double‐ligand co‐assembly strategy. Furthermore, the SLAs show assembly‐level elastic and anisotropic deformation responses to external stimuli as a result of the long‐range anisotropic molecular packing, which provides SLAs with new application potentials in bio‐mimic nanomechanics. [ABSTRACT FROM AUTHOR]

Eine Unterdrückung des Quantentunnelns im Nullfeld und feldinduziertes Quantentunneln der Magnetisierung wurden in einem Holmium(III) ‐ Einzelmolekülmagnet beobachtet und von J. ‐ L. Liu, M. ‐ L. Tong et al. in der Zuschrift auf S. 5078 beschrieben. Diese Dynamik wird auf die Kombination einer günstigen pentagonal ‐ bipyramidalen Kristallfeldumgebung mit den Hyperfeinwechselwirkungen von 165Ho (I=7/2) mit einer natürlichen Häufigkeit von 100 % zurückgeführt. [ABSTRACT FROM AUTHOR]

Typical n‐type conjugated polymers are based on fused‐ring electron‐accepting building blocks. Herein, we report a non‐fused‐ring strategy to design n‐type conjugated polymers, i.e. introducing electron‐withdrawing imide or cyano groups to each thiophene unit of a non‐fused‐ring polythiophene backbone. The resulting polymer, n‐PT1, shows low LUMO/HOMO energy levels of −3.91 eV/−6.22 eV, high electron mobility of 0.39 cm2 V−1 s−1 and high crystallinity in thin film. After n‐doping, n‐PT1 exhibits excellent thermoelectric performance with an electrical conductivity of 61.2 S cm−1 and a power factor (PF) of 141.7 μW m−1 K−2. This PF is the highest value reported so far for n‐type conjugated polymers and this is the first time for polythiophene derivatives to be used in n‐type organic thermoelectrics. The excellent thermoelectric performance of n‐PT1 is due to its superior tolerance to doping. This work indicates that polythiophene derivatives without fused rings are low‐cost and high‐performance n‐type conjugated polymers. [ABSTRACT FROM AUTHOR]

PbS quantum dots (QDs) are promising building blocks for solution‐processed short‐wavelength infrared (SWIR) devices. The recently developed direct synthesis of semi‐conductive PbS QD inks has substantially simplified the preparation processing and reduced the material cost, while facing the challenge to synthesize large‐size QDs with absorption covering the SWIR region. Herein, we for the first time realize a low‐cost, scalable synthesis of SWIR PbS QD inks after an extensive investigation of the reaction kinetics. Finally, based on these PbS SWIR QD inks, the solar cell demonstrates a record‐high power conversion efficiency (PCE) of 1.44 % through an 1100 nm cutoff silicon filter and the photodetector device shows a low dark current density of 2×10−6 A cm−2 at −0.8 V reverse bias with a high external quantum efficiency (EQE) of 70 % at ≈1300 nm. Our results realize the direct synthesis of low‐cost and scalable SWIR QD inks and may accelerate the industrialization of consumer SWIR technologies. [ABSTRACT FROM AUTHOR]

Abstract: p–π conjugation with embedded heteroatoms offers unique opportunities to tune the electronic structure of conjugated polymers. An approach is presented to form highly electron‐deficient p–π conjugated polymers based on triarylboranes, demonstrate their n‐type behavior, and explore device applications. By combining alternating [2,4,6‐tris(trifluoromethyl)phenyl]di(thien‐2‐yl)borane (FBDT) and electron‐deficient isoindigo (IID)/pyridine‐flanked diketopyrrolopyrrole (DPPPy) units, we achieve low‐lying lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels, high electron mobilities, and broad absorptions in the visible region. All‐polymer solar cells with these polymers as electron acceptors exhibit encouraging photovoltaic performance with power conversion efficiencies of up to 2.83 %. These results unambiguously prove the n‐type behavior and demonstrate the photovoltaic applications of p–π conjugated polymers based on triarylborane. [ABSTRACT FROM AUTHOR]

To solve the problems such as the dissolution and the poor conductivity of organic small molecule electrode materials, we construct π‐d conjugated coordination polymer Ni‐DHBQ with multiple redox‐active centers as lithium storage materials. It exhibits an ultra‐high capacity of 9‐electron transfers, while the π‐d conjugation and the laminar structure inside the crystal ensure fast electron transport and lithium ion diffusion, resulting in excellent rate performance (505.6 mAh g−1 at 1 A g−1 after 300 cycles). The interaction of Ni‐DHBQ with the binder CMC synergistically inhibits its dissolution and anchors the Ni atoms, thus exhibiting excellent cycling stability (650.7 mAh g−1 at 0.1 A g−1 after 100 cycles). This work provides insight into the mechanism of lithium storage in π‐d conjugated coordination polymers and the synergistic effect of CMC, which will contribute to the molecular design and commercial application of organic electrode materials. [ABSTRACT FROM AUTHOR]

High charge carrier mobility polymer semiconductors are always semi‐crystalline. Amorphous conjugated polymers represent another kind of polymer semiconductors with different charge transporting mechanism. Here we report the first near‐amorphous n‐type conjugated polymer with decent electron mobility, which features a remarkably rigid, straight and planar polymer backbone. The molecular design strategy is to copolymerize two fused‐ring building blocks which are both electron‐accepting, centrosymmetrical and planar. The polymer is the alternating copolymer of double B←N bridged bipyridine (BNBP) unit and benzobisthiazole (BBTz) unit. It shows a decent electron mobility of 0.34 cm2 V−1 s−1 in organic field‐effect transistors. The excellent electron transporting property of the polymer is possibly due to the ultrahigh backbone stiffness, small π‐π stacking distance, and high molecular weight. [ABSTRACT FROM AUTHOR]

Aqueous batteries that use metal anodes exhibit maximum anodic capacity, whereas the energy density is still unsatisfactory partially due to the high redox potential of the metal anode. Current metal anodes are plagued by the dilemma that the redox potential of Zn is not low enough, whereas Al, Mg, and others with excessively low redox potential cannot work properly in aqueous electrolytes. Mn metal with a suitably low redox potential is a promising candidate, which was rarely explored before. Here, we report a rechargeable aqueous Mn‐metal battery enabled by a well‐designed electrolyte and robust inorganic–organic interfaces. The inorganic Sn‐based interface with a bottom‐up microstructure was constructed to preliminarily suppress water decomposition. With this bubble‐free interface, the organic interface can be formed via an esterification reaction of sucrose triggered by acyl chloride in the electrolyte, generating a dense physical shield that isolates water while permitting Mn2+ diffusion. Hence, a Mn symmetric cell achieves a superior plating/stripping stability for 200 hours, and a Mn||V2O5 battery maintains approximately 100 % capacity after 200 cycles. Moreover, the Mn||V2O5 battery realizes a much higher output voltage than that of the Zn||V2O5 battery, evidencing the possibility of increasing the energy density through using a Mn anode. This work develops a systematic strategy to stabilize a Mn‐metal anode for Mn‐metal batteries, opening a new door towards enhanced voltage of aqueous batteries. [ABSTRACT FROM AUTHOR]

Introducing magnetic switchability into artificial molecular machines is fascinating for precise control of magnetism via external stimuli. Herein, a field‐induced CoII single‐molecule magnet was found to exhibit the reversible switch of Jahn–Teller distortion near room temperature, along with thermal conformational motion of the 18‐crown‐6 rotor, which pulls the coordinated H2O to rotate through intermolecular hydrogen bonds and triggers a single‐crystal‐to‐single‐crystal phase transition with Twarm=282 K and Tcool=276 K. Interestingly, the molecular magnetic anisotropy probed by single‐crystal angular‐resolved magnetometry revealed the reorientation of easy axis by 14.6°. Moreover, ON/OFF negative magnetodielectric effects were respectively observed in the high‐/low‐temperature phase, which manifests the spin‐lattice interaction in the high‐temperature phase could be stronger, in accompanied by the hydrogen bonding between the rotating 18‐crown‐6 and the coordinated H2O. [ABSTRACT FROM AUTHOR]

We describe herein the self‐assembly synthesis of an octanuclear CoII [2]catenane {[Co4(H2L)6]216+} formed by the mechanical interlocking of two {[Co4(H2L)6]8+} rectangles of unprecedented topology. Subtle manipulation of the synthetic conditions allows the isolation of a mixed‐valence [Co2III/Co2II]10+ non‐catenated rectangle. The CoII centers in the [2]catenane exhibit slow relaxation of their magnetic moment, i. e. single‐molecule magnet properties, dominated by quantum tunneling and Raman relaxation processes. This work shows that metallo‐supramolecular chemistry can precisely control the organization of single‐molecule magnets in topologically complex arrangements. [ABSTRACT FROM AUTHOR]

Here we reported the deuteration of the metal‐binding equatorial water molecules in a reported HoIII single‐molecule magnet (SMM) with pentagonal‐bipyramidal geometry, from [Ho(CyPh2PO)2(H2O)5]3+ to [Ho(CyPh2PO)2(D2O)5]3+. The hyperfine structures originating from the nuclear spin of 165HoIII can be clearly observed. Moreover, the resulting magnetization dynamics revealed the switch of the relative relaxation rates for the two isotope‐isomorphic complexes—respectively faster/slower at low/high temperature. The noticeable isotope effect arises from not only the paramagnetic metal center but also the diamagnetic ligands, which can be explained by the ab initio calculated tunnel splitting and the involvement of the super‐hyperfine interaction related to the difference in the nuclear spin number of protium (1H, I=1/2) and deuterium (2H, I=1). [ABSTRACT FROM AUTHOR]

Modulation of A‐site defects is crucial to the redox reactions on ABO3 perovskites for both clean air application and electrochemical energy storage. Herein we report a scalable one‐pot strategy for in situ regulation of La vacancies (VLa) in LaMnO3.15 by simply introducing urea in the traditional citrate process, and further reveal the fundamental relationship between VLa creation and surface lattice oxygen (Olatt) activation. The underlying mechanism is shortened Mn−O bonds, decreased orbital ordering, promoted MnO6 bending vibration and weakened Jahn–Teller distortion, ultimately realizing enhanced Mn‐3d and O‐2p orbital hybridization. The LaMnO3.15 with optimized VLa exhibits order of magnitude increase in toluene oxidation and ca. 0.05 V versus RHE (reversible hydrogen electrode) increase of half‐wave potential in oxygen reduction reaction (ORR). The reported strategy can benefit the development of novel defect‐meditated perovskites in both heterocatalysis and electrocatalysis. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Organic radical ferroics such as TEMPO have attracted widespread interest. However, the relatively low Curie temperature of 287 K and melting point of 311 K severely hinder its application potential. Despite extensive interest, high‐temperature radical ferroics have not yet been found. Here, taking advantage of chemical design and supramolecular radical chemistry, we designed two high‐temperature organic supramolecular radical ferroics [(NH3‐TEMPO)([18]crown‐6)](ReO4) (1) and [(NH3‐TEMPO)([18]crown‐6)](ClO4) (2), which can retain ferroelectricity up to 413 K and 450 K, respectively. To our knowledge, they are both the first supramolecular radical ferroics and unprecedented high‐temperature radical ferroics, where the supramolecular component is vital for the stabilization of the radical and extending the working temperature window. Both also have paramagnetism, non‐interacting spin moments, and excellent piezoelectric and electrostrictive behaviors comparable to that of LiNbO3. [ABSTRACT FROM AUTHOR]

Acceptor–acceptor (A‐A) copolymerization is an effective strategy to develop high‐performance n‐type conjugated polymers. However, the development of A‐A type conjugated polymers is challenging due to the synthetic difficulty. Herein, a distannylated monomer of strong electron‐deficient double B←N bridged bipyridine (BNBP) unit is readily synthesized and used to develop A‐A type conjugated polymers by Stille polycondensation. The resulting polymers show ultralow LUMO energy levels of −4.4 eV, which is among the lowest value reported for organoboron polymers. After n‐doping, the resulting polymers exhibit electric conductivity of 7.8 S cm−1 and power factor of 24.8 μW m−1 K−2. This performance is among the best for n‐type polymer thermoelectric materials. These results demonstrate the great potential of A‐A type organoboron polymers for high‐performance n‐type thermoelectrics. [ABSTRACT FROM AUTHOR]

Combining Ising‐type magnetic anisotropy with collinear magnetic interactions in single‐molecule magnets (SMMs) is a significant synthetic challenge. Herein we report a Dy[15‐MCCu‐5] (1‐Dy) SMM, where a DyIII ion is held in a central pseudo‐D5h pocket of a rigid and planar Cu5 metallacrown (MC). Linking two Dy[15‐MCCu‐5] units with a single hydroxide bridge yields the double‐decker {Dy[15‐MCCu‐5]}2 (2‐Dy) SMM where the anisotropy axes of the two DyIII ions are nearly collinear, resulting in magnetic relaxation times for 2‐Dy that are approximately 200 000 times slower at 2 K than for 1‐Dy in zero external field. Whereas 1‐Dy and the YIII‐diluted Dy@2‐Y analogue do not show remanence in magnetic hysteresis experiments, the hysteresis data for 2‐Dy remain open up to 6 K without a sudden drop at zero field. In conjunction with theoretical calculations, these results demonstrate that the axial ferromagnetic Dy–Dy coupling suppresses fast quantum tunneling of magnetization (QTM). The relaxation profiles of both complexes curiously exhibit three distinct exponential regimes, and hold the largest effective energy barriers for any reported d–f SMMs up to 625 cm−1. [ABSTRACT FROM AUTHOR]

This work reports on an assembling–calcining method for preparing gold–metal oxide core–satellite nanostructures, which enable surface‐enhanced Raman spectroscopic detection of chemical reactions on metal oxide nanoparticles. By using the nanostructure, we study the photooxidation of Si−H catalyzed by CuO nanoparticles. As evidenced by the in situ spectroscopic results, oxygen vacancies of CuO are found to be very active sites for oxygen activation, and hydroxide radicals (*OH) adsorbed at the catalytic sites are likely to be the reactive intermediates that trigger the conversion from silanes into the corresponding silanols. According to our finding, oxygen vacancy‐rich CuO catalysts are confirmed to be of both high activity and selectivity in photooxidation of various silanes. [ABSTRACT FROM AUTHOR]

Lanthanide permanent magnets are widely used in applications ranging from nanotechnology to industrial engineering. However, limited access to the rare earths and rising costs associated with their extraction are spurring interest in the development of lanthanide‐free hard magnets. Zero‐ and one‐dimensional magnetic materials are intriguing alternatives due to their low densities, structural and chemical versatility, and the typically mild, bottom‐up nature of their synthesis. Here, we present two one‐dimensional cobalt(II) systems Co(hfac)2(R‐NapNIT) (R‐NapNIT=2‐(2′‐(R‐)naphthyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide, R=MeO or EtO) supported by air‐stable nitronyl nitroxide radicals. These compounds are single‐chain magnets and exhibit wide, square magnetic hysteresis below 14 K, with giant coercive fields up to 65 or 102 kOe measured using static or pulsed high magnetic fields, respectively. Magnetic, spectroscopic, and computational studies suggest that the record coercivities derive not from three‐dimensional ordering but from the interaction of adjacent chains that compose alternating magnetic sublattices generated by crystallographic symmetry. [ABSTRACT FROM AUTHOR]

Glucose transporters play an essential role in cancer cell proliferation and survival and have been pursued as promising cancer drug targets. Using microarrays of a library of new macrocycles known as rapafucins, which were inspired by the natural product rapamycin, we screened for new inhibitors of GLUT1. We identified multiple hits from the rapafucin 3D microarray and confirmed one hit as a bona fide GLUT1 ligand, which we named rapaglutin A (RgA). We demonstrate that RgA is a potent inhibitor of GLUT1 as well as GLUT3 and GLUT4, with an IC50 value of low nanomolar for GLUT1. RgA was found to inhibit glucose uptake, leading to a decrease in cellular ATP synthesis, activation of AMP‐dependent kinase, inhibition of mTOR signaling, and induction of cell‐cycle arrest and apoptosis in cancer cells. Moreover, RgA was capable of inhibiting tumor xenografts in vivo without obvious side effects. RgA could thus be a new chemical tool to study GLUT function and a promising lead for developing anticancer drugs. [ABSTRACT FROM AUTHOR]

Abstract: Multinuclear heterometallic nanoclusters with controllable stoichiometry and structure are anticipated to possess promising catalytic, magnetic, and optical properties. Heterometallic nanoclusters with precise stoichiometry of Bi3Cu4 and Bi7Cu12 can be stabilized in the scaffold of two‐dimensional metal–organic networks on a Cu(111) surface through on‐surface metallosupramolecular self‐assembly processes. The atomic structures of the nanoclusters were resolved using scanning tunneling microscopy and density functional theory calculations. The nanoclusters feature highly symmetric planar hexagonal shapes and core–shell charge modulation. The clusters are arranged as triangular lattices with a periodicity that can be tuned by choosing molecules of different size. This work shows that on‐surface metallosupramolecular self‐assembly creates unique possibilities for the design and synthesis of multinuclear heterometallic nanoclusters. [ABSTRACT FROM AUTHOR]

Abstract: We disclose a novel strategy to design n‐type acenes through the introduction of boron–nitrogen coordination bonds (B←N). We synthesized two azaacenes composed of two B←N units and six/eight linearly annelated rings. The B←N unit significantly perturbed the electronic structures of the azaacenes: Unique LUMOs delocalized over the entire acene skeletons and decreased aromaticity of the B←N‐adjacent rings. Most importantly, these B←N‐containing azaacenes exhibited low‐lying LUMO energy levels and high electron affinities, thus leading to n‐type character. The solution‐processed organic field‐effect transistor based on one such azaacene exhibited unipolar n‐type characteristics with an electron mobility of 0.21 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]