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Generating circularly polarized luminescence (CPL) with simultaneous high photoluminescence quantum yield (PLQY) and dissymmetry factor (glum) is difficult due to usually unmatched electric transition dipole moment (μ) and magnetic transition dipole moment (m) of materials. Herein we tackle this issue by playing a "cascade cationic insertion" trick to achieve strong CPL (with PLQY of ~100 %) in lead‐free metal halides with high glum values reaching −2.3×10−2 without using any chiral inducers. Achiral solvents of hydrochloric acid (HCl) and N, N‐dimethylformamide (DMF) infiltrate the crystal lattice via asymmetric hydrogen bonding, distorting the perovskite structure to induce the "intrinsic" chirality. Surprisingly, additional insertion of Cs+ cation to substitute partial (CH3)2NH2+ transforms the chiral space group to achiral but the crystal maintains chiroptical activity. Further doping of Sb3+ stimulates strong photoluminescence as a result of self‐trapped excitons (STEs) formation without disturbing the crystal framework. The chiral perovskites of indium‐antimony chlorides embedded on LEDs chips demonstrate promising potential as CPL emitters. Our work presents rare cases of chiroptical activity of highly luminescent perovskites from only achiral building blocks via spontaneous resolution as a result of symmetry breaking. [ABSTRACT FROM AUTHOR]

Air stable n‐type conductive molecules with high electrical conductivities and excellent device performance have important applications in organic electronics, but their synthesis remains challenging. Herein, we report three self‐doped n‐type conductive molecules, designated QnNs, with a closed‐shell quinoidal backbone and alkyl amino chains of different lengths. The QnNs are self‐doped by intermolecular electron transfer from the amino groups to the quinoidal backbone. This process is ascertained unambiguously by experiments and theoretical calculations. The use of a quinoidal structure effectively improves the self‐doping level, and thus increases the electrical conductivity of self‐doped n‐type conductive molecules achieved by a closed‐shell structure from<10−4 S cm−1 to>0.03 S cm−1. Furthermore, the closed‐shell quinoidal structure results in good air stability of the QnNs, with half‐lives>73 days; and Q4N shows an electrical conductivity of 0.019 S cm−1 even after exposure to air for 120 days. When applying Q6N as the cathode interlayer in organic solar cells (OSCs), an outstanding power conversion efficiency of up to 18.2 % was obtained, which represents one the best results in binary OSCs. [ABSTRACT FROM AUTHOR]

Microenvironment regulation of M‐N4 single‐atom catalysts (SACs) is a promising way to tune their catalytic properties toward the electrochemical CO2 reduction reaction. However, strategies that can effectively introduce functional groups around the M‐N4 sites through strong covalent bonding and under mild reaction conditions are highly desired. Taking the hydrophilic Ni‐N4 SAC as a representative, we report herein a [2+1] cycloaddition reaction between Ni‐N4 and in situ generated difluorocarbene (F2C:), and enable the surface fluorocarbonation of Ni‐N4, resulting in the formation of a super‐hydrophobic Ni‐N4‐CF2 catalyst. Meanwhile, the mild reaction conditions allow Ni‐N4‐CF2 to inherit both the electronic and structural configuration of the Ni‐N4 sites from Ni‐N4. Enhanced electrochemical CO2‐to‐CO Faradaic efficiency above 98 % is achieved in a wide operating potential window from −0.7 V to −1.3 V over Ni‐N4‐CF2. In situ spectroelectrochemical studies reveal that a highly hydrophobic microenvironment formed by the −CF2− group repels asymmetric H‐bonded water at the electrified interface, inhibiting the hydrogen evolution reaction and promoting CO production. This work highlights the advantages of [2+1] cycloaddition reactions on the covalent modification of N‐doped carbon‐supported catalysts. [ABSTRACT FROM AUTHOR]

A divergent synthesis of skeletally distinct arboridinine and arborisidine was achieved. The central divergent strategy was inspired by the divergent biosynthetic cyclization mode of arboridinine and arborisidine and their hidden topological connection. The branch point was reached through a Michael and Mannich cascade process. A site‐selective intramolecular Mannich reaction was developed to construct the tetracyclic core of arboridinine, while a site‐selective intramolecular α‐amination of ketone was used to access the tetracyclic core of arborisidine. A strategic Peterson olefination through intramolecular nucleophile delivery was able to set up the exocyclic olefin of arboridinine. [ABSTRACT FROM AUTHOR]

We describe herein the assembly of the cis‐decalin framework through radical cyclization initiated by metal‐catalyzed hydrogen atom transfer (MHAT), further applied it in the asymmetric synthesis of dankasterones A and B and periconiastone A. Position‐selective C−H oxygenation allowed for installation of the necessary functionality. A radical rearrangement was adopted to create 13(14→8)abeo‐8‐ergostane skeleton. Interconversion of dankasterone B and periconiastone A was realized through biomimetic intramolecular aldol and retro‐aldol reactions. The MHAT‐based approach, serves as a new dissection means, is complementary to the conventional ways to establish cis‐decalin framework. [ABSTRACT FROM AUTHOR]

Zinc ion batteries (ZIBs) exhibit significant promise in the next generation of grid‐scale energy storage systems owing to their safety, relatively high volumetric energy density, and low production cost. Despite substantial advancements in ZIBs, a comprehensive evaluation of critical parameters impacting their practical energy density (Epractical) and calendar life is lacking. Hence, we suggest using formulation‐based study as a scientific tool to accurately calculate the cell‐level energy density and predict the cycling life of ZIBs. By combining all key battery parameters, such as the capacity ratio of negative to positive electrode (N/P), into one formula, we assess their impact on Epractical. When all parameters are optimized, we urge to achieve the theoretical capacity for a high Epractical. Furthermore, we propose a formulation that correlates the N/P and Coulombic efficiency of ZIBs for predicting their calendar life. Finally, we offer a comprehensive overview of current advancements in ZIBs, covering cathode and anode, along with practical evaluations. This Minireview outlines specific goals, suggests future research directions, and sketches prospects for designing efficient and high‐performing ZIBs. It aims at bridging the gap from academia to industry for grid‐scale energy storage. [ABSTRACT FROM AUTHOR]

Zinc ion hybrid capacitors (ZIHCs) are promising energy storage devices for emerging flexible electronics, but they still suffer from trade‐off in energy density and cycling life. Herein, we show that such a dilemma can be well‐addressed by deploying ZnCl2 based electrolytes. Combining experimental studies and density functional theory (DFT) calculations, for the first time, we demonstrate an intriguing chloride ion (Cl−) facilitated desolvation mechanism in hydrated [ZnCl]+(H2O)n−1 (with n=1–6) clusters. Based on this mechanism, a water‐in‐salt type hydrogel electrolyte filled with ZnCl2 was developed to concurrently improve the energy storage capacity of porous carbon materials and the reversibility of Zn metal electrode. The resulting ZIHCs deliver a battery‐level energy density up to 217 Wh kg−1 at a power density of 450 W kg−1, an unprecedented cycling life of 100 000 cycles, together with excellent low‐temperature adaptability and mechanical flexibility. [ABSTRACT FROM AUTHOR]

The development of transition‐metal‐oxides (TMOs)‐based bifunctional catalysts toward efficient overall water splitting through delicate control of composition and structure is a challenging task. Herein, the rational design and controllable fabrication of unique heterostructured inter‐doped ruthenium–cobalt oxide [(Ru–Co)Ox] hollow nanosheet arrays on carbon cloth is reported. Benefiting from the desirable compositional and structural advantages of more exposed active sites, optimized electronic structure, and interfacial synergy effect, the (Ru–Co)Ox nanoarrays exhibited outstanding performance as a bifunctional catalyst. Particularly, the catalyst showed a remarkable hydrogen evolution reaction (HER) activity with an overpotential of 44.1 mV at 10 mA cm−2 and a small Tafel slope of 23.5 mV dec−1, as well as an excellent oxygen evolution reaction (OER) activity with an overpotential of 171.2 mV at 10 mA cm−2. As a result, a very low cell voltage of 1.488 V was needed at 10 mA cm−2 for alkaline overall water splitting. [ABSTRACT FROM AUTHOR]

An unprecedented rhodium(III)-catalyzed hydroarylation of α,α-difluoromethylene alkynes with N-pivaloxyl aroylamides through sequential C−H activation and aryl migration is detailed herein. A large array of α,α-difluoromethylene alkynes and N-pivaloxyl aryl amides were amenable to this transformation, thus providing a novel synthetic protocol for the construction of difluorinated 2-alkenyl aniline derivatives in high yields and with excellent regioselectivity. Notably, unique fluorine effects were found to underlie the thus unconventional reaction manifold. [ABSTRACT FROM AUTHOR]

Solar‐driven CO2 reduction and water oxidation to liquid fuels represents a promising solution to alleviate energy crisis and climate issue, but it remains a great challenge for generating CH3OH and CH3CH2OH dominated by multi‐electron transfer. Single‐cluster catalysts with super electron acceptance, accurate molecular structure, customizable electronic structure and multiple adsorption sites, have led to greater potential in catalyzing various challenging reactions. However, accurately controlling the number and arrangement of clusters on functional supports still faces great challenge. Herein, we develop a facile electrosynthesis method to uniformly disperse Wells‐Dawson‐ and Keggin‐type polyoxometalates on TiO2 nanotube arrays, resulting in a series of single‐cluster functionalized catalysts P2M18O62@TiO2 and PM12O40@TiO2 (M=Mo or W). The single polyoxometalate cluster can be distinctly identified and serves as electronic sponge to accept electrons from excited TiO2 for enhancing surface‐hole concentration and promote water oxidation. Among these samples, P2Mo18O62@TiO2‐1 exhibits the highest electron consumption rate of 1260 μmol g−1 for CO2‐to‐CH3OH conversion with H2O as the electron source, which is 11 times higher than that of isolated TiO2 nanotube arrays. This work supplied a simple synthesis method to realize the single‐dispersion of molecular cluster to enrich surface‐reaching holes on TiO2, thereby facilitating water oxidation and CO2 reduction. [ABSTRACT FROM AUTHOR]

[FeFe] hydrogenases demonstrate remarkable catalytic efficiency in hydrogen evolution and oxidation processes. However, susceptibility of these enzymes to oxygen‐induced degradation impedes their practical deployment in hydrogen‐production devices and fuel cells. Recent investigations into the oxygen‐stable (Hinact) state of the H‐cluster revealed its inherent capacity to resist oxygen degradation. Herein, we present findings on Cl‐ and SH‐bound [2Fe‐2S] complexes, bearing relevance to the oxygen‐stable state within a biological context. A characteristic attribute of these complexes is the terminal Cl−/SH− ligation to the iron center bearing the CO bridge. Structural analysis of the t‐Cl demonstrates a striking resemblance to the Hinact state of DdHydAB and CbA5H. The t‐Cl/t‐SH exhibit reversible oxidation, with both redox species, electronically, being the first biomimetic analogs to the Htrans and Hinact states. These complexes exhibit notable resistance against oxygen‐induced decomposition, supporting the potential oxygen‐resistant nature of the Htrans and Hinact states. The swift reductive release of the Cl‐/SH‐group demonstrates its labile and kinetically controlled binding. The findings garnered from these investigations offer valuable insights into properties of the enzymatic O2‐stable state, and key factors governing deactivation and reactivation conversion. This work contributes to the advancement of bio‐inspired molecular catalysts and the integration of enzymes and artificial catalysts into H2‐evolution devices and fuel‐cell applications. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) with low crystallinity are promising candidates for application in organic thermoelectrics (OTEs), particularly in flexible devices, because the disordered structures of these CPs can effectively accommodate dopants and ensure robust resistance to bending. However, n‐doped CPs usually exhibit poor thermoelectric performance, which hinders the development of high‐performance thermoelectric generators. Herein, we report an n‐type CP (ThDPP‐CNBTz) comprising two acceptor units: a thiophene‐flanked diketopyrrolopyrrole and a cyano‐functionalized benzothiadiazole. ThDPP‐CNBTz shows a low LUMO energy level of below −4.20 eV and features low crystallinity, enabling high doping efficiency. Moreover, the dual‐acceptor design enhances polaron delocalization, resulting in good thermoelectric performance. After n‐doping, ThDPP‐CNBTz exhibits an average electrical conductivity (σ) of 50.6 S cm−1 and a maximum power factor (PF) of 126.8 μW m−1 K−2, which is among the highest values reported for solution‐processed n‐type CPs to date. Additionally, a solution‐processed flexible OTE device based on doped ThDPP‐CNBTz exhibits a maximum PF of 70 μW m−1 K−2; the flexible device also shows remarkable resistance to bending strain, with only a marginal change in σ after 600 bending cycles. The findings presented in this work will advance the development of n‐type CPs for OTE devices, and flexible devices in particular. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc batteries are promising but hindered by unfavorable dendrite growth and side reactions on zinc anodes. In this study, we demonstrate a fast melting‐solidification approach for effectively converting commercial Zn foils into single (002)‐textured Zn featuring millimeter‐sized grains. The melting process eliminates initial texture, residual stress, and grain size variations in diverse commercial Zn foils, guaranteeing the uniformity of commercial Zn foils into single (002)‐textured Zn. The single (002)‐texture ensures large‐scale epitaxial and dense Zn deposition, while the reduction in grain boundaries significantly minimizes intergranular reactions. These features enable large grain single (002)‐textured Zn shows planar and dense Zn deposition under harsh conditions (100 mA cm−2, 100 mAh cm−2), impressive reversibility in Zn||Zn symmetric cell (3280 h under 1 mA cm−2, 830 h under 10 mAh cm−2), and long cycling stability over 180 h with a high depth of discharge value of 75 %. This study successfully addresses the issue of uncontrollable texture formation in Zn foils following routine annealing treatments with temperatures below the Zn melting point. The findings of this study establish a highly efficient strategy for fabricating highly reversible single (002)‐textured Zn anodes. [ABSTRACT FROM AUTHOR]

There is growing evidence that pillaring up a densely packed ultramicroporous two‐dimensional (2D) structure is an effective strategy to reduce their internal diffusion. Reliable pillaring paradigms, however, is rather challenging. Here we report a one‐pot multi‐component sequential assembly method for the preparation of a new self‐pillared 2D polymer and ultramicroporous carbon with integrated surface protrusions. The molecular level pillaring process is surprisingly fast, that is, in 10 min. The thickness of nanoplate edge and the density (roughness), angle as well as height of protrusions can be precisely tuned. Exemplified in coal bed methane purification/separation, this unique pillared 2D carbons exhibit a CH4/N2 selectivity up to 24 at a low CH4 partial pressure and two orders of magnitude faster CH4 diffusion kinetics than the commercial carbon molecular sieves. This solution synthesis methodology is generalizable for creation and fine tuning of pillared 2D heterostructures. [ABSTRACT FROM AUTHOR]

Green production of NH3, especially the Li‐mediated electrochemical N2 reduction reaction (NRR) in non‐aqueous solutions, is attracting research interest. Controversies regarding the NRR mechanism greatly impede its optimization and wide applications. To understand the electrocatalytic process, we treated Au coated carbon fibrous paper (Au/CP) as the model catalyst. In situ XRD confirmed the transformation of lithium intermediates during NRR. Au greatly improved electron transfer kinetics to catalyze metallic Li formation, and accordingly highly accelerated spontaneous NRR. The Faradaic efficiency of NRR on Au/CP reached 34.0 %, and NH3 yield was as high as 50 μg h−1 cm−2. Our research shows that the key step of Li‐mediated non‐aqueous NRR is electrocatalytic Li reduction and offers a novel electrocatalyst design method for Li reduction. [ABSTRACT FROM AUTHOR]

Stable Zn anodes with a high utilization efficiency pose a challenge due to notorious dendrite growth and severe side reactions. Therefore, electrolyte additives are developed to address these issues. However, the additives are always consumed by the electrochemical reactions over cycling, affecting the cycling stability. Here, hexamethylphosphoric triamide (HMPA) is reported as an electrolyte additive for achieving stable cycling of Zn anodes. HMPA reshapes the solvation structures and promotes anion decomposition, leading to the in situ formation of inorganic‐rich solid‐electrolyte‐interphase. More interestingly, this anion decomposition does not involve HMPA, preserving its long‐term impact on the electrolyte. Thus, the symmetric cells with HMPA in the electrolyte survive ≈500 h at 10 mA cm−2 for 10 mAh cm−2 or ≈200 h at 40 mA cm−2 for 10 mAh cm−2 with a Zn utilization rate of 85.6 %. The full cells of Zn||V2O5 exhibit a record‐high cumulative capacity even under a lean electrolyte condition (E/C ratio=12 μL mAh−1), a limited Zn supply (N/P ratio=1.8) and a high areal capacity (6.6 mAh cm−2). [ABSTRACT FROM AUTHOR]

Zn metal as one of promising anode materials for aqueous batteries suffers from notorious dendrite growth, serious Zn corrosion and hydrogen evolution. Here, a bifunctional electrolyte additive, N‐methyl pyrrolidone (NMP), is developed to improve the electrochemical performance of Zn anode. NMP not only alters the solvation structure of Zn2+, but also in situ produces a dense N‐rich solid‐electrolyte‐interphase layer on Zn foils. This layer protects Zn foils from corrosive electrolytes and benefits the uniform plating/stripping of Zn. Hence, the asymmetrical cells with NMP in the electrolyte retain a high coulombic efficiency of 99.8 % over 1000 cycles. The symmetric cells survive ≈200 h for 10 mAh cm−2 at a high Zn utilization of 85.6 %. The full cells of Zn||MnO2 show an impressive cumulative capacity even with lean electrolyte (E/C ratio=10 μL mAh−1), limited Zn supply (N/P ratio=2.3) and high areal capacity (5.0 mAh cm−2). [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 (CO2RR) into high value‐added chemicals is an attractive route to achieve carbon neutrality. However, the development of an efficient catalyst for CO2RR is still largely by trial‐and‐error and is very time‐consuming. Herein, we built an electrocatalyst testing platform featuring a home‐built automatic flow cell to accelerate the discovery of efficient catalysts. A fast screening of 109 Cu‐based bimetallic catalysts in only 55 h identifies Mg combined with Cu as the best electrocatalyst for CO2 to C2+ products. The thus designed Mg−Cu catalyst achieves a Faradaic efficiency (FE) of C2+ products up to 80 % with a current density of 1.0 A cm−2 at −0.77 V versus reversible hydrogen electrode (RHE). Systematic experiments with in situ spectroelectrochemistry analyses show that Mg2+ species stabilize Cu+ sites during CO2RR and promote the CO2 activation, thus enhancing the *CO coverage to promote C−C coupling. [ABSTRACT FROM AUTHOR]

Modern applications of 2D NMR spectroscopy to diagnostic screening, metabolomics, quality control, and other high-throughput applications are often limited by the time-consuming sampling requirements along the indirect time domain t1. 2D total correlation spectroscopy (TOCSY) provides unique spin connectivity information for the analysis of a large number of compounds in complex mixtures, but standard methods typically require >100 t1 increments for an accurate spectral reconstruction, rendering these experiments ineffective for high-throughput applications. For a complex metabolite mixture it is demonstrated that absolute minimal sampling (AMS), based on direct fitting of resonance frequencies and amplitudes in the time domain, yields an accurate spectral reconstruction of TOCSY spectra using as few as 16 t1 points. This permits the rapid collection of homonuclear 2D NMR experiments at high resolution with measurement times that previously were only the realm of 1D experiments. [ABSTRACT FROM AUTHOR]

The first total synthesis of hamigerans D, G, L, and N-Q has been accomplished. A convergent approach was used to build the basic tricarbocyclic ring system bearing a 5-6-6 structure. A sequence of oxidative cleavage, homologation, and ring regeneration provided access to the 5-7-6 skeleton of hamigeran G. Based on the biogenetic hypothesis, elegant and highly efficient biomimetic transformations of hamigeran G into hamigerans D, N-Q, and L were achieved. [ABSTRACT FROM AUTHOR]

The residual tumor after surgery is the most significant prognostic factor of patients with epithelial ovarian cancer. Near‐infrared (NIR) fluorescence‐guided surgery is actively utilized for tumor localization and complete resection during surgery. However, currently available contrast‐enhancing agents display low on‐target binding, unfavorable pharmacokinetics, and toxicity, thus not ideal for clinical use. Here we report ultrabright and stable squaraine fluorophores with optimal pharmacokinetics by introducing an asymmetric molecular conformation and surface charges for rapid transporter‐mediated cellular uptake. Among the tested, OCTL14 shows low serum binding and rapid distribution into cancer tissue via organic cation transporters (OCTs). Additionally, the charged squaraine fluorophores are retained in lysosomes, providing durable intraoperative imaging in a preclinical murine model of ovarian cancer up to 24 h post‐injection. OCTL14 represents a significant departure from the current bioconjugation approach of using a non‐targeted fluorophore and would provide surgeons with an indispensable tool to achieve optimal resection. [ABSTRACT FROM AUTHOR]

Three‐dimensional covalent organic frameworks (3D COFs) have gained increasing attention for their attractive features. However, the development of 3D COFs is strongly restricted, mainly due to their synthetic difficulty and complicated structure determination. Post‐synthetic modification, which can avoid these problems by incorporating functional moieties into a predetermined framework, provides an alternative way to construct 3D COFs with specific functions. Herein, we report the designed synthesis and characterization of a series of highly crystalline 3D COFs with different loadings of ethynyl groups. Notably, these alkyne‐tagged 3D COFs provide a platform for targeted anchoring various specific groups onto the pore walls via click reactions. Moreover, the pore surface engineering can accordingly change their properties, for example, the obtained click products exhibited higher CO2/N2 selectivity. We describe a simple but powerful strategy to build functional 3D COFs, which will certainly advance them for a ranging of interesting applications in the future. [ABSTRACT FROM AUTHOR]

Silver forges the ring: A new and practical silver‐catalyzed [5+2] cycloaddition method has been developed for the synthesis of azepines through the formation of four new chemical bonds between a γ‐amino ketone and an alkyne in one step. This method provides a new hetero‐[5+2] cycloaddition strategy for the construction of seven‐membered ring systems. [ABSTRACT FROM AUTHOR]

The stereoselectivity and yield in glycosylation reactions are paramount but unpredictable. We have developed a database of acceptor nucleophilic constants (Aka) to quantify the nucleophilicity of hydroxyl groups in glycosylation influenced by the steric, electronic and structural effects, providing a connection between experiments and computer algorithms. The subtle reactivity differences among the hydroxyl groups on various carbohydrate molecules can be defined by Aka, which is easily accessible by a simple and convenient automation system to assure high reproducibility and accuracy. A diverse range of glycosylation donors and acceptors with well‐defined reactivity and promoters were organized and processed by the designed software program "GlycoComputer" for prediction of glycosylation reactions without involving sophisticated computational processing. The importance of Aka was further verified by random forest algorithm, and the applicability was tested by the synthesis of a Lewis A skeleton to show that the stereoselectivity and yield can be accurately estimated. [ABSTRACT FROM AUTHOR]

Although the Turing structures, or stationary reaction‐diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing‐type Ag2Se on CoSe2 nanobelts relied on diffusion‐driven instability. The resultant Turing‐type Ag2Se‐CoSe2 material is highly effective to catalyze the oxygen evolution reaction (OER) in alkaline electrolytes with an 84.5 % anodic energy efficiency. Electrochemical measurements show that the intrinsic OER activity correlates linearly with the length of Ag2Se‐CoSe2 interfaces, determining that such Turing‐type interfaces are more active sites for OER. Combing X‐ray absorption and computational simulations, we ascribe the excellent OER performance to the optimized adsorption energies for critical oxygen‐containing intermediates at the unconventional interfaces. [ABSTRACT FROM AUTHOR]

We report the design of a bifunctional metal–organic layer (MOL), Hf12‐Ru‐Co, composed of [Ru(DBB)(bpy)2]2+ [DBB‐Ru, DBB=4,4′‐di(4‐benzoato)‐2,2′‐bipyridine; bpy=2,2′‐bipyridine] connecting ligand as a photosensitizer and Co(dmgH)2(PPA)Cl (PPA‐Co, dmgH=dimethylglyoxime; PPA=4‐pyridinepropionic acid) on the Hf12 secondary building unit (SBU) as a hydrogen‐transfer catalyst. Hf12‐Ru‐Co efficiently catalyzed acceptorless dehydrogenation of indolines and tetrahydroquinolines to afford indoles and quinolones. We extended this strategy to prepare Hf12‐Ru‐Co‐OTf MOL with a [Ru(DBB)(bpy)2]2+ photosensitizer and Hf12 SBU capped with triflate as strong Lewis acids and PPA‐Co as a hydrogen transfer catalyst. With three synergistic active sites, Hf12‐Ru‐Co‐OTf competently catalyzed dehydrogenative tandem transformations of indolines with alkenes or aldehydes to afford 3‐alkylindoles and bisindolylmethanes with turnover numbers of up to 500 and 460, respectively, illustrating the potential use of MOLs in constructing novel multifunctional heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Two‐electrode solar rechargeable devices trigger intense attention due to their potential applications in solar energy conversion and storage. However, interface energy barriers lead to severe loss of output voltage and negligible dark discharge current. Therefore, external biases are required for dark discharge in these devices, limiting their practical applications. Herein, we report a new two‐electrode device of Si/WO3/H2SO4(aq)/C that can work without bias. The device has the highest dark output power among all of the two‐electrode solar rechargeable devices. The device based on a Si/WO3 junction indicates photoinduced adjustable interface barrier height during charge transfer, which can overcome the energy barrier and realize dark discharge without bias. Owing to the interface characteristics, the Si/WO3 is designated as a capacitor‐type Faradaic junction. [ABSTRACT FROM AUTHOR]

In this work, an artificial electrode/electrolyte (E/E) interface, made by coating the electrode surface with a quaternary ammonium cation (R4N+) surfactant, was successfully developed, leading to a change in the CO2 reduction reaction (CO2RR) pathway. This artificial E/E interface, with high CO2 permeability, promotes CO2 transportation and hydrogenation, as well as suppresses the hydrogen evolution reaction (HER). Linear and branched surfactants facilitated formic acid and CO production, respectively. Molecular dynamics simulations show that the artificial interface provided a facile CO2 diffusion pathway. Moreover, density‐functional theory (DFT) calculations revealed the stabilization of the key intermediate, OCHO*, through interactions with R4N+. This strategy might also be applicable to other electrocatalytic reactions where gas consumption is involved. [ABSTRACT FROM AUTHOR]

2D covalent organic frameworks (COFs) are receiving ongoing attention in semiconductor photocatalysis. Herein, we present a photocatalytic selective chemical transformation by combining sp2 carbon‐conjugated porphyrin‐based covalent organic framework (Por‐sp2c‐COF) photocatalysis with TEMPO catalysis illuminated by 623 nm red light‐emitting diodes (LEDs). Highly selective conversion of amines into imines was swiftly afforded in minutes. Specifically, the π‐conjugation of porphyrin linker leads to extensive absorption of red light; the sp2 −C=C− double bonds linkage ensures the stability of Por‐sp2c‐COF under high concentrations of amine. Most importantly, we found that crystalline framework of Por‐sp2c‐COF is pivotal for cooperative photocatalysis with (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO). This work foreshadows that the outstanding hallmarks of COFs, particularly crystallinity, could be exploited to address energy and environmental challenges by cooperative photocatalysis. [ABSTRACT FROM AUTHOR]

Flexible zinc–air batteries (ZAB) are a promising battery candidate for emerging flexible electronic devices, but the catalysis‐based working principle and unique semi‐opened structure pose a severe challenge to their overall performance at cold temperature. Herein, we report the first flexible rechargeable ZAB with excellent low‐temperature adaptability, based on the innovation of an efficient electrocatalyst to offset the electrochemical performance shrinkage caused by decreased temperature and a highly conductive hydrogel with a polarized terminal group to render the anti‐freezing property. The fabricated ZABs show excellent electrochemical performances that outperform those of many aqueous ZABs at room temperature. They also deliver a high capacity of 691 mAh g−1 and an energy density of 798 Wh kg−1 at −20 °C (92.7 % and 87.2 % retention of the room temperature counterparts, respectively), together with excellent flexibility and reverting capability. [ABSTRACT FROM AUTHOR]

The construction of 2D and 3D covalent organic frameworks (COFs) from functional moieties for desired properties has gained much attention. However, the influence of COFs dimensionality on their functionalities, which can further assist in COF design, has never been explored. Now, by selecting designed precursors and topology diagrams, 2D and 3D porphyrinic COFs (2D‐PdPor‐COF and 3D‐PdPor‐COF) are synthesized. By model building and Rietveld refinement of powder X‐ray diffraction, 2D‐PdPor‐COF crystallizes as 2D sheets while 3D‐PdPor‐COF adopts a five‐fold interpenetrated pts topology. Interestingly, compared with 2D‐PdPor‐COF, 3D‐PdPor‐COF showed interesting properties, including 1) higher CO2 adsorption capacity; 2) better photocatalytic performance; and 3) size‐selective photocatalysis. Based on this study, we believe that with the incorporation of functional moieties, the dimensionality of COFs can definitely influence their functionalities. [ABSTRACT FROM AUTHOR]

A series of 1,3‐indandione‐terminated π‐conjugated quinoids were synthesized by alkoxide‐mediated rearrangement reaction of the respective alkene precursors, followed by air oxidation. This new protocol allows access to quinoidal compounds with variable termini and cores. The resulting quinoids all show LUMO levels below −4.0 eV and molar extinction coefficients above 105 L mol−1 cm−1. The optoelectronic properties of these compounds can be regulated by tuning the central cores as well as the aryl termini ascribed to the delocalized frontier molecular orbitals over the entire molecular skeleton involving aryl termini. n‐Channel organic thin‐film transistors with electron mobility of up to 0.38 cm2 V−1 s−1 were fabricated, showing the potential of this new class of quinoids as organic semiconductors. [ABSTRACT FROM AUTHOR]

The superhydrophobicity of intrinsically hydrophilic materials is still not well understood. Now, intrinsically hydrophilic metal oxides with different topographic structures are taken as model materials to reveal the origin of their superhydrophobicity. These metal oxides show enhanced hydrophobicity or superhydrophobicity in O2 relative to that in air, but exhibit superhydrophilic behavior in N2. The presence of rich oxygen vacancies greatly enhanced the adsorption of O2 with an adsorption energy larger than N2 and H2O, resulting in a stable O2 adsorption rather than air‐trapping within grooves of rough‐textured surfaces, which endows these intrinsically hydrophilic oxides with superhydrophobicity. Our results highlight a further understanding of the origin of superhydrophobicity for intrinsically hydrophilic materials, and is of great significance for designing novel devices with desired wettability. [ABSTRACT FROM AUTHOR]

Stereocontrolled chemical glycosylation remains a major challenge despite vast efforts reported over many decades and so far still mainly relies on trial and error. Now it is shown that the relative reactivity value (RRV) of thioglycosides is an indicator for revealing stereoselectivities according to four types of acceptors. Mechanistic studies show that the reaction is dominated by two distinct intermediates: glycosyl triflates and glycosyl halides from N‐halosuccinimide (NXS)/TfOH. The formation of glycosyl halide is highly correlated with the production of α‐glycoside. These findings enable glycosylation reactions to be foreseen by using RRVs as an α/β‐selectivity indicator and guidelines and rules to be developed for stereocontrolled glycosylation. [ABSTRACT FROM AUTHOR]

Immobilization of planar CoII‐2,3‐naphthalocyanine (NapCo) complexes onto doped graphene resulted in a heterogeneous molecular Co electrocatalyst that was active and selective to reduce CO2 into CO in aqueous solution. A systematic study revealed that graphitic sulfoxide and carboxyl dopants of graphene were the efficient binding sites for the immobilization of NapCo through axial coordination and resulted in active Co sites for CO2 reduction. Compared to carboxyl dopants, the sulfoxide dopants further improved the electron communication between NapCo and graphene, which led to the increase of turnover frequency of the Co sites by about 3 times for CO production with a Faradic efficiency up to 97 %. Pristine NapCo in the absence of a graphene support did not display efficient electron communication with the electrode and thus failed to serve as the electrochemical active site for CO2 reduction under the identical conditions. [ABSTRACT FROM AUTHOR]

Herein, we reported the designed synthesis of three isostructural three‐dimensional covalent organic frameworks (3D COFs) with ‐H, ‐Me, or ‐F substituents, which have similar crystallinity and topology. Their crystal structures were determined by continuous rotation electron diffraction (cRED), and all three 3D COFs were found to adopt a fivefold interpenetrated pts topology. More importantly, the resolution of these cRED datasets reached up to 0.9–1.0 Å, enabling the localization of all non‐hydrogen atomic positions in a COF framework directly by 3D ED techniques for the first time. In addition, the precise control of the pore environments through the use of different functional groups led to different selectivities for CO2 over N2. We have thus confirmed that polycrystalline COFs can be definitely studied to the atomic level as other materials, and this study should also inspire the design and synthesis of 3D COFs with tailored pore environments for interesting applications. [ABSTRACT FROM AUTHOR]

The construction of stable covalent organic frameworks (COFs) for various applications is highly desirable. Herein, we report the synthesis of a novel two‐dimensional (2D) porphyrin‐based sp2 carbon‐conjugated COF (Por‐sp2c‐COF), which adopts an eclipsed AA stacking structure with a Brunauer—Emmett—Teller surface area of 689 m2 g−1. Owing to the C=C linkages, Por‐sp2c‐COF shows a high chemical stability under various conditions, even under harsh conditions such as 9 m HCl and 9 m NaOH solutions. Interestingly, Por‐sp2c‐COF can be used as a metal‐free heterogeneous photocatalyst for the visible‐light‐induced aerobic oxidation of amines to imines. More importantly, in comparison to imine‐linked Por‐COF, the inherent structure of Por‐sp2c‐COF equips it with several advantages as a photocatalyst, including reusability and high photocatalytic performance. This clearly demonstrates that sp2 carbon‐linked 2D COFs can provide an interesting platform for heterogeneous photocatalysis. [ABSTRACT FROM AUTHOR]

The first iron-catalyzed 1,2-difunctionalization of styrenes and conjugated alkenes with silanes and either N or C, using an oxidative radical strategy, is described. Employing FeCl2 and di- tert-butyl peroxide allows divergent alkene 1,2-difunctionalizations, including 1,2-aminosilylation, 1,2-arylsilylation, and 1,2-alkylsilylation, which rely on a wide range of nucleophiles, namely, amines, amides, indoles, pyrroles, and 1,3-dicarbonyls, thus providing a powerful platform for producing diverse silicon-containing alkanes. [ABSTRACT FROM AUTHOR]

Zn metal as one of promising anode materials for aqueous batteries suffers from notorious dendrite growth, serious Zn corrosion and hydrogen evolution. Here, a bifunctional electrolyte additive, N‐methyl pyrrolidone (NMP), is developed to improve the electrochemical performance of Zn anode. NMP not only alters the solvation structure of Zn2+, but also in situ produces a dense N‐rich solid‐electrolyte‐interphase layer on Zn foils. This layer protects Zn foils from corrosive electrolytes and benefits the uniform plating/stripping of Zn. Hence, the asymmetrical cells with NMP in the electrolyte retain a high coulombic efficiency of 99.8 % over 1000 cycles. The symmetric cells survive ≈200 h for 10 mAh cm−2 at a high Zn utilization of 85.6 %. The full cells of Zn||MnO2 show an impressive cumulative capacity even with lean electrolyte (E/C ratio=10 μL mAh−1), limited Zn supply (N/P ratio=2.3) and high areal capacity (5.0 mAh cm−2). [ABSTRACT FROM AUTHOR]

Metal-organic layers (MOLs) represent an emerging class of tunable and functionalizable two-dimensional materials. In this work, the scalable solvothermal synthesis of self-supporting MOLs composed of [Hf6O4(OH)4(HCO2)6] secondary building units (SBUs) and benzene-1,3,5-tribenzoate (BTB) bridging ligands is reported. The MOL structures were directly imaged by TEM and AFM, and doped with 4′-(4-benzoate)-(2,2′,2′′-terpyridine)-5,5′′-dicarboxylate (TPY) before being coordinated with iron centers to afford highly active and reusable single-site solid catalysts for the hydrosilylation of terminal olefins. MOL-based heterogeneous catalysts are free from the diffusional constraints placed on all known porous solid catalysts, including metal-organic frameworks. This work uncovers an entirely new strategy for designing single-site solid catalysts and opens the door to a new class of two-dimensional coordination materials with molecular functionalities. [ABSTRACT FROM AUTHOR]

Finding a common path: A synthetic strategy inspired by the proposed biogenesis of the montanine‐type alkaloids enabled the concise asymmetric synthesis of these compounds in a divergent fashion on the basis of an unprecedented tandem oxidative dearomatization/intramolecular aza‐Michael addition as the key step. This bioinspired approach revealed a chemical connection between the cherylline‐ and montanine‐type alkaloids (see scheme). [ABSTRACT FROM AUTHOR]

The new material consists of abundant Turing-type Ag SB 2 sb Se-CoSe SB 2 sb interfaces, which are active sites that allow for favorable chemisorption of surface oxygenated species, leading to enhanced energetics for the oxygen evolution reaction. Energy efficiency, multi-interface, oxygen evolution, reaction-diffusion model, Turing structure Keywords: energy efficiency; multi-interface; oxygen evolution; reaction-diffusion model; Turing structure EN energy efficiency multi-interface oxygen evolution reaction-diffusion model Turing structure 6828 6828 1 03/10/21 20210315 NES 210315 B Turing patterns b have been widely seen in living systems. [Extracted from the article]

The cover page for the April 11, 2016 issue of the journal "Angewandte Chemie International Edition" is presented.