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How Nature synthesizes enantiomerically pure substances from achiral or racemic resources remains a mystery. In this study, we aimed to emulate this natural phenomenon by constructing chiral tetrahedral cages through self‐assembly, achieved by condensing two achiral compounds–a trisamine and a trisaldehyde. The occurrence of intercomponent CH⋅⋅⋅π interactions among the phenyl building blocks within the cage frameworks results in twisted conformations, imparting planar chirality to the tetrahedrons. In instances where the trisaldehyde precursor features electron‐withdrawing ester side chains, we observed that the intermolecular CH⋅⋅⋅π forces are strong enough to prevent racemization. To attain enantioselective self‐assembly, a chiral amine was introduced during the imine formation process. The addition of three equivalents of chiral amino mediator to one equivalent of the achiral trisaldehyde precursor formed a trisimino intermediate. This chiral compound was subsequently combined with the achiral trisamino precursor, leading to an imine exchange reaction that releasing the chiral amino mediator and formation of the tetrahedral cage with an enantiomeric excess (ee) of up to 75 %, exclusively composed of achiral building blocks. This experimental observation aligns with theoretical calculations based on the free energies of related cage structures. Moreover, since the chiral amine was not consumed during the imine exchange cycle, it enabled the enantioselective self‐assembly of the tetrahedral cage for multiple cycles when new batches of the achiral trisaldehyde and trisamino precursors were successively added. [ABSTRACT FROM AUTHOR]

In biological systems, molecular assembly primarily relies on the assistance of molecular chaperones. Inspired by nature, strategies like 'chaperone‐assisted assembly' and 'catalyzed assembly' have been proposed for the sophisticated control of molecular assembly. Nonetheless, significant challenges remain in the rational design of such systems, calling for a deep understanding of underlying principles. Herein, we demonstrate an artificial chaperone serves a dual role, that is catalyst in low dosages and inhibitor in high dosages, in regulating the supramolecular polymerization of peptides. Low dosages of carboxymethyl cellulose, as the chaperones, catalyze the assembly of Aβ16‐22 peptides into fibrils through multi‐step phase separation, while high dosages trap the peptides into coacervate intermediates and therefore inhibit the fibrillation. Consequently, the quantity of chaperones does not follow the intuition that 'more is better' for catalyzing assembly but instead has an optimal molar ratio. Investigation reveals that the interplay and evolution of electrostatic and hydrophobic interactions are the keys to achieving these processes. This study provides insights into the multifaceted roles artificial chaperones may play in a dosage‐dependent manner and enriches the toolkit for efficient and controllable construction of complex assembly systems. [ABSTRACT FROM AUTHOR]

Galangin is an important flavonoid with natural activity, that is abundant in galangal and propolis. Currently, various biological activities of galangin have been disclosed, including anti‐inflammation, antibacterial effect, anti‐oxidative stress and aging, anti‐fibrosis, and antihypertensive effect. Based on the above bioactivities, more and more attention has been paid to the role of galangin in neurodegenerative diseases, rheumatoid arthritis, osteoarthritis, osteoporosis, skin diseases, and cancer. In this paper, the natural sources, pharmacokinetics, bioactivities, and therapeutic potential of galangin against various diseases were systematically reviewed by collecting and summarizing relevant literature. In addition, the molecular mechanism and new preparation of galangin in the treatment of related diseases are also discussed, to broaden the application prospect and provide reference for its clinical application. Furthermore, it should be noted that current toxicity and clinical studies of galangin are insufficient, and more evidence is needed to support its possibility as a functional food. [ABSTRACT FROM AUTHOR]

The development of high‐performance cathode materials for next‐generation lithium‐ion batteries (LIBs) is urgently needed. Among the potential cathode candidates, ternary layer oxide LiNi1/3Co1/3Mn1/3O2 (LNCM) has attracted considerable attention due to its high voltage discharge, large theoretical specific capacity, stable chemical structure and low cost. However, Li+/Ni2+ cation mixing and low conductivity have resulted in poor long‐term cyclability, voltage drop and capacity degradation during high‐rate charging. To address these issues, a sol‐gel technique together with an annealing treatment was used to prepare LNCM with well‐defined structure and good morphology. The material obtained by heating the LNCM precursor at 850 °C for 12 h (LNCM‐850/12) exhibited an initial discharge specific capacity of 217.9 mAh g−1 at 0.2 C and maintained a high reversible capacity of 116.1 mAh g−1 after 200 cycles. The LNCM‐850/12 electrode also demonstrated superior rate capacity and exceptional cycling stability due to its well‐defined structure, low Li+/Ni2+ cation mixing and good morphology. These characteristics improve the electrical/ionic conductivity, reduce the charge transfer resistance and shorten the Li+ diffusion distance, ultimately accelerating the Li+ insertion and extraction. Overall, the careful control of calcination time in LNCM synthesis provides valuable insights for the development of advanced cathodes for LIBs. [ABSTRACT FROM AUTHOR]

Taking abundant and sustainable solar energy as the only energy source, solar‐powered interface evaporation has been regarded as a promising method to alleviate the pressure of freshwater shortage. However, the uptake of clean water from brine is constantly accompanied by evaporation of water and condensation of vapor, which inevitably generates salt solid, preventing further continuous and stable evaporation. The most direct method is to fabricate a photothermal material with salt self‐resistance by using the reflux of salt ions. Here, a superhydrophilic interconnected biomass carbon absorber (SBCA) is prepared by freeze‐drying and carbonization, realizing strong liquid pumping, and self‐blocking salt. In combination with superior broadband light absorption (94.91%), high porosity (95.9%), superhydrophilicity, and excellent thermal localization, an evaporation device with excellent evaporation rate (2.45 kg m−2 h−1 under 1 kW m−2) is successfully proposed. In the meantime, the porous skeleton and rapid water transport can enhance the diffusion of salt ions and slow down the rate of salt deposition. As a result, no salt deposition is found on the SBCA surface after continuous irradiation at 1 kW m−2 for 15 h. The design can provide a convenient and low‐cost efficient strategy for solar steam generators to address clean water acquisition. [ABSTRACT FROM AUTHOR]

The activation of DNA‐dependent kinase (DNA‐PKcs) upon DNA damage contains a cascade of reactions, covering acetylation by TIP60, binding with Ku70/80, and autophosphorylation. However, how cells regulate TIP60‐mediated acetylation of DNA‐PKcs and the following DNA‐PKcs activation upon DNA damage remains obscure. This present study reported that TIP60 is hyper‐SUMOylated in normal conditions, but upon irradiation‐induced DNA damage, small ubiquitin‐like modifier (SUMO)‐specific protease 3 (SENP3)‐mediated deSUMOylation of TIP60 promoted its interaction with DNA‐PKcs to form the TIP60‐DNA‐PKcs complex. We show that TIP60 SUMOylation is reduced quickly in response to DNA damage and the deSUMOylation of TIP60 by SENP3 is required for DNA‐PKcs acetylation and its autophosphorylation. Comet and γH2AX immunofluorescence assay showed that knockdown of SENP3 impaired DNA damage repair. Using the NHEJ report system, we found that knockdown of SENP3 affected the efficiency of NHEJ. Further exploration using clonogenic survival assay, cell viability assay and cytoflow assay suggested that leaking SENP3 increased the sensitivity of tumour cells to serval DNA damage treatment. Overall, our findings revealed a previously unidentified role of SENP3 in regulating DNA‐PKcs activity and DNA damage repair. [ABSTRACT FROM AUTHOR]

Quercitrin is a naturally available type of flavonoid that commonly functions as the dietary ingredient and supplement. So far, a wide spectrum of bioactivities of quercitrin have been revealed, including antioxidative stress, antiinflammation, anti‐microorganisms, immunomodulation, analgesia, wound healing, and vasodilation. Based on these various pharmacological activities, increasing studies have focused on the potency of quercitrin in diverse diseases in recent years, such as bone metabolic diseases, gastrointestinal diseases, cardiovascular and cerebrovascular diseases, and others. In this paper, by collecting and summarizing publications from the recent years, the natural sources, pharmacological activities and roles in various diseases, pharmacokinetics, structure–activity relationship, as well as the toxicity of quercitrin were systematically reviewed. In addition, the underlying molecular mechanisms of quercitrin in treating related diseases, the dose‐effect relationships, and the novel preparations were discussed on the purpose of broadening the application prospect of quercitrin as functional food and providing reference for its clinical application. Notably, clinical studies of quercitrin are insufficient at present, further high‐quality studies are needed to firmly establish the clinical efficacy of quercitrin. [ABSTRACT FROM AUTHOR]

The rapid depletion of lithium resources and the increasing demand for electrical energy storage have stimulated the pursuit of emerging electrochemical energy storage. Aqueous zinc ion batteries (ZIBs) are highly sought after for their low cost, high safety, and increased environmental compatibility. However, the search for suitable cathode materials is still tricky for a wide range of researchers. Vanadium oxides (VxOy), with their abundant vanadium valence, easily deformable V−O polyhedrons, and tunable chemical compositions, are of significant advantage in developing emerging materials. This work provides a detailed review of different VxOy for the application in aqueous ZIBs. The current problems and optimization strategies of VxOy cathode materials are systematically discussed. Finally, the current challenges and possible directions for future research of VxOy cathode materials in aqueous ZIBs are presented. [ABSTRACT FROM AUTHOR]

Cu2V2O7 is an important material to improve low conductivity of Li4Ti5O12. Herein, Li4Ti5O12/Cu2V2O7 with different Cu2V2O7 ratios is successfully prepared by a liquid phase‐assisted dispersion method. The results show that the electrochemical properties of Li4Ti5O12 are affected by the Cu2V2O7 content incorporated in the composites. Among all obtained samples, Li4Ti5O12/0.05 Cu2V2O7 reveals the best electrochemical performance and capacity retention rate, and its first cycle specific capacity is 246.3/197.2 mAh g−1 when the current density is 30 mA g−1 and it maintains values of 175.8/175 mAh g−1 for 200 cycles between 1.0 and 3.0 V. The resulting Li4Ti5O12/0.05 Cu2V2O7 composite also displays higher capacities at elevated current densities of 120 and 1200 mA g−1, with values always superior to those of the original Li4Ti5O12. The detailed electrode dynamics analysis illustrates that the introduced Cu2V2O7 phase in the composites improves the cycle stability and lithium‐ion transfer rate of Li4Ti5O12. Through in situ X‐ray diffractometry (XRD) test analysis of the Li4Ti5O12/0.05 Cu2V2O7 composite material, it is confirmed that the lithium storage mechanism is improved, where metallic Cu is formed in situ during each charge and discharge reaction process; thereby, the electronic conductivity of the composite material is improved and charge transfer resistance of the bulk material is reduced. [ABSTRACT FROM AUTHOR]

Background: To study the influences of posterior tibial nerve stimulation (PTNS) on neurogenic bladder and the expression of transient receptor potential (TRP) channels and P2X receptors in rats with spinal cord injury (SCI) and explore the possible mechanism. Methods: SCI model was established by modified Allen's method and PTNS was performed. Urodynamic indexes and Haematoxylin and Eosine staining of bladder tissue were used to evaluate the therapeutic effect. The expression of TRP channels and P2X receptors in the bladder and dorsal root ganglia (DRG) was detected by real‐time PCR and Western blot. Results: The low compliance of bladder in treatment group was significantly improved compared with SCI group, and the infiltration of inflammatory cells in bladder tissue was significantly reduced. At the same time, the expression of TRP and P2X in bladder and DRG was partially restored after the treatment of PTNS. Conclusions: PTNS is an effective therapy for SCI‐induced neurogenic bladder via the TRP/P2X signaling pathway. [ABSTRACT FROM AUTHOR]

Self‐assembly of host molecules in aqueous media via metal–ligand coordination is well developed. However, the preparation of purely covalent counterparts in water has remained a formidable task. An anionic tetrahedron cage was successfully self‐assembled in a [4+4] manner by condensing a trisamine and a trisformyl in water. Even although each individual imine bond is rather labile and apt to hydrolyze in water, the tetrahedron is remarkably stable or inert due to multivalence. The tetrahedral cages, as well as its neutral counterparts dissolved in organic solvent, have homochirality, namely that their four propeller‐shaped trisformyl residues adopt the same rotational conformation. The cage is able to take advantage of hydrophobic effect to accommodate a variety of guest molecules in water. When a chiral guest was recognized, the formation of one enantiomer of the cage became more favored relative to the other. As a consequence, the cage could be produced in an enantioselective manner. The tetrahedron is able to maintain its chirality after removal of the chiral guest—probably on account of the cooperative occurrence of intramolecular forces that restrict the intramolecular flipping of phenyl units in the cage framework. [ABSTRACT FROM AUTHOR]

Quantitatively predicting the reactivity of dynamic covalent reaction is essential to understand and rationally design complex structures and reaction networks. Herein, the reactivity of aldehydes and amines in various rapid imine formation in aqueous solution by microfluidic NMR spectroscopy was quantified. Investigation of reaction kinetics allowed to quantify the forward rate constants k+ by an empirical equation, of which three independent parameters were introduced as reactivity parameters of aldehydes (SE, E) and amines (N). Furthermore, these reactivity parameters were successfully used to predict the unknown forward rate constants of imine formation. Finally, two competitive reaction networks were rationally designed based on the proposed reactivity parameters. Our work has demonstrated the capability of microfluidic NMR spectroscopy in quantifying the kinetics of label‐free chemical reactions, especially rapid reactions that are complete in minutes. [ABSTRACT FROM AUTHOR]

Condensation of an inherently C3‐symmetric polychlorotriphenylmethyl (PTM) radical trisaldehyde with tris(2‐aminoethyl)amine (TREN) yields a [4+4] tetrahedral radical cage as a racemic pair of homochiral enantiomers in 75 % isolated yield. The structure was characterized by X‐ray crystallography, confirming the homochirality of each cage framework. The homochirality results from intramolecular [CH⋅⋅⋅π] and hydrogen‐bonding interactions within the cage framework. The four PTM radicals in a cage undergo weak through‐space coupling. Magnetic measurements demonstrated that each cage bears 3.58 spins. [ABSTRACT FROM AUTHOR]

Supramolecular eutectogels, an emerging class of materials that have just developed very recently, offer a new opportunity for generating functional supramolecular gel materials in biocompatible anhydrous or low‐water media. As the first example of supramolecular G4 eutectogels, complexes of natural guanosine and H3BO3 exhibited excellent gelation capacity in choline chloride/alcohol deep eutectic solvents. The as‐prepared supramolecular eutectogels displayed unexpected solvent‐induced chiral inversion and significantly high ionic conductivity (up to 7.78 mS cm−1), as well as outstanding thixotropic/injectable properties, high thermal stability and excellent electrochromic activity. These features make these versatile supramolecular G4 eutectogels promising candidates for developing next‐generation flexible electronics with low environmental impact. [ABSTRACT FROM AUTHOR]

Ethylene glycol‐assisted sol‐gel method is employed for preparing LiNi1/3Co1/3Mn1/3O2 used as cathode material in lithium‐ion batteries. The prepared material has higher c/a value and lower cationic mixing degree of Li+/Ni2+, illuminating a more orderly structure, smaller particle size and more regular particle shape, which shorten the diffusion length for Li+ ions and allow the rapid kinetics of Li+ ions diffusion. Sure enough, the as‐prepared LiNi1/3Co1/3Mn1/3O2 material displays the first discharge capacity of 208 mAh g−1 and keeps 133 mAh g−1 after 200 cycles between 2.5 and 4.5 V at 0.2 C. In addition, it demonstrates excellent rate capacity of 143 mAh g−1 at 2 C. The results show that LiNi1/3Co1/3Mn1/3O2 prepared by this method has high discharge capacity, admirable rate capability and exceptional cycle stability, which provides significant insights into the synthesis of other layered oxides as cathode materials for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

In this study, the electrochemical performances of anthraquinone (C14H8O2) without modification, anthraquinone‐1‐sulfonic acid sodium (C14H7NaO5S) and anthraquinone‐1,5‐disulfonic acid disodium salts (C14H6Na2O8S2) as organic cathode materials for sodium‐ion batteries are reported for the first time. Ionizable sodium sulfonate functional groups lead to a significant enhancement of the structural stability of C14H8O2, yielding excellent cycle and rate performance. The C14H6Na2O8S2 and C14H7NaO5S electrodes exhibit initial discharge capacities of 195 and 209 mAh g−1, which are maintained at 131 and 93 mAh g−1, respectively, after 100 cycles at a current density of 30 mA g−1. Even at a high rate of 480 mA g−1, the initial discharge capacity of C14H6Na2O8S2 is 114 mAh g−1, indicating a high rate capability. Also, the results show that the carbonyl group is the Na+ storage location during charge/discharge. Owing to their superior electrochemical performance, these organic cathode materials demonstrate promise for use in environmentally friendly, sustainable sodium‐ion batteries. The electrochemical performances of anthraquinone (AQ) and the sodium and disodium salts (AQS and AQDS) as organic cathode materials for sodium‐ion batteries are studied. Ionizable sodium sulfonate functional groups lead to a significant enhancement of the structural stability of AQ, yielding excellent cycle and rate performances. [ABSTRACT FROM AUTHOR]

LiV3O8 material with high discharge capacity has attracted increasing attention as cathode material for lithium‐ion batteries (LIBs). However, LiV3O8 is still limited by its weak dissolution and change of lattice structure. In this study, Mg3(PO4)2 fully coated LiV3O8 nanoparticles are successfully prepared by rheological phase reaction and surface deposition. The thickness of Mg3(PO4)2 coating layer is estimated to 24.7 nm for surface‐modified LiV3O8 with Mg3(PO4)2 content of 1.0 wt.%. The as‐prepared Mg3(PO4)2 coated‐LiV3O8 is utilized as cathode and showed high initial capacity of 323.93 mAh g−1. In addition, it maintained stable capacity of 250.82 mAh g−1 after 50 cycles at the current rate of 60 mA g−1 between 1.8 and 4.0 V. This value was much higher than that of bare LiV3O8. Besides, even at current density of 240 mA g−1, its capacity keeps 170.89 mAh g−1 after 50 cycles. The detailed quantitative kinetics analyses confirm the fundamental reasons behind the enhanced rate capability and cycling stability. Overall, this work opens up novel avenues towards the design of protecting cathode materials, which could broaden applications of insoluble phosphates. Rod‐like Mg3(PO4)2 coated−LiV3O8 were successfully prepared through the rheological phase, then coated by ex‐situ formed Mg3(PO4)2. 1.0 wt.% Mg3(PO4)2 coated sample shows the uniform coated layer with the thickness of 24.7 nm, and delivers a high‐rate capacity of 220.06 mAh g−1 at 240 mA g−1. The detailed quantitative kinetics analyses confirm that surface‐controlled behaviors effectively enhance rate capability and cycling stability. [ABSTRACT FROM AUTHOR]

Abstract: Different dimensions of carbon materials with various features have captured numerous interests due to their applications on the tremendous fields. Restricted by the raw materials and devices, the controlling of their morphology is a major challenge. Utilizing the catalytic features of the intermediates from the low‐cost salts and polymerization of 0D carbon quantum dots (CQDs), 0D CQDs are expected to self‐assemble into 1/2/3D carbon structures with the assistance of temperature‐induced intermediates (e.g., ZnO, Ni, and Cu) from the salts (ZnCl2, NiCl2, and CuCl). The formation mechanisms are illustrated as follows: 1) the “orient induction” to evoke “vine style” growth mechanism of ZnO; 2) the “dissolution–precipitation” of Ni; and 3) the “surface adsorption self‐limited” of Cu. Subsequently, the degree of graphitization, interlayer distance, and special surface area are investigated in detail. 1D structure from 700 °C as anode displays a high Na‐storage capacity of 301.2 mAh g−1 at 0.1 A g−1 after 200 cycles and 107 mAh g−1 at 5.0 A g−1 after 5000 cycles. Quantitative kinetics analysis confirms the fundamentals of the enhanced rate capacity and the potential region of Na‐insertion/extraction. This elaborate work opens up an avenue toward the design of carbon with multidimensions and in‐depth understanding of their sodium‐storage features. [ABSTRACT FROM AUTHOR]

Threonylcarbamoyladenosine (t6A) is a modified nucleoside universally conserved in tRNAs in all three kingdoms of life. The recently discovered genes for t6A synthesis, including tsaC and tsaD, are essential in model prokaryotes but not essential in yeast. These genes had been identified as antibacterial targets even before their functions were known. However, the molecular basis for this prokaryotic-specific essentiality has remained a mystery. Here, we show that t6A is a strong positive determinant for aminoacylation of tRNA by bacterial-type but not by eukaryotic-type isoleucyl-tRNA synthetases and might also be a determinant for the essential enzyme tRNAIle-lysidine synthetase. We confirm that t6A is essential in Escherichia coli and a survey of genome-wide essentiality studies shows that genes for t6A synthesis are essential in most prokaryotes. This essentiality phenotype is not universal in Bacteria as t6A is dispensable in Deinococcus radiodurans, Thermus thermophilus, Synechocystis PCC6803 and Streptococcus mutans. Proteomic analysis of t6A- D. radiodurans strains revealed an induction of the proteotoxic stress response and identified genes whose translation is most affected by the absence of t6A in tRNAs. Thus, although t6Ais universally conserved in tRNAs, its role in translation might vary greatly between organisms. [ABSTRACT FROM AUTHOR]

A novel [4+2] cycloaddition reaction between osmium alkenylcarbyne complex [OsHCl2{CC(PPh3)CHPh}(PPh3)2]+BF4− ( 1) and nitriles (acetonitrile and benzonitrile) provided metallapyridiniums [OsCl2{CHC(PPh3)CPhCRNH}(PPh3)2]+BF4− (R=CH3 ( 2), Ph ( 3)) and OsCl3{CHC(PPh3)CPhCPhNH}(PPh3) ( 4). A possible mechanism was proposed. Treatment of 2 with n-BuLi and NEt3 afforded osmapyridines OsCl2{CHC(PPh3)CPhCCH3N}(PPh3)2 ( 5) and [OsCl{CHC(PPh3)CPhCCH3N}(C6H5N)(PPh3)2]+BF4− ( 6). The ligands of osmapyridiniums 2 and 4 were changed, thus providing a series of osmapyridiniums [OsCl(SCN){CHC(PPh3)CPhC(CH3)NH}(PPh3)2]+Cl − ( 7), OsCl(SCN)2{CHC(PPh3)CPhC(CH3)NH}(PPh3) ( 8), Os(SCN)3{CHC(PPh3)CPhC(CH3)NH}(PPh3) ( 9), [OsCl{CHC(PPh3)CPhC(CH3)NH}(CH3CN)(PPh3)2]+(BF4−)2 ( 10), [OsCl{CHC(PPh3)CPhC(CH3)NH}-( η2-1,10-phenanthroline)(PPh3)]+(BF4−)Cl− ( 11), [OsCl{CHC(PPh3)CPhC(CH3)NH}(η2-8-hydroxyquinoline) (PPh3)]+BF4− ( 12), and [Os{CHC(PPh3)CPhCPhNH}(CH3CN)3(PPh3)]+(BF4−)3 ( 13). Most of these products were characterized by NMR spectroscopy, elemental analysis and single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Keywords: dynamic covalent chemistry; homochirality; organic cages; organic radicals; self-assembly EN dynamic covalent chemistry homochirality organic cages organic radicals self-assembly 1 1 1 04/22/21 20210426 NES 210426 B Dynamische kovalente Chemie b In der Zuschrift auf S. 9940 präsentieren Tianyu Jiao, Xiaoyu Cao, Hao Li et al. einen selbstorganisierten homochiralen Radikalkäfig mit paramagnetischem Verhalten. Frontispiz: A Self-Assembled Homochiral Radical Cage with Paramagnetic Behaviors Dynamic covalent chemistry, homochirality, organic cages, organic radicals, self-assembly. [Extracted from the article]

Newly developed charge storage and charge transport materials, such as organic polymers, demonstrate promise for applications in secondary batteries. Currently, such organic materials are regarded as promising candidates as substitutes for traditional metal materials for energy storage equipment because of advantages such as structural diversity, abundance, and environmental friendliness. The structural characteristics, electrochemical reaction mechanism, and properties of polymer electrode materials are comprehensively introduced. In addition, recent progress on implementing polymer‐based materials in lithium‐ and sodium‐ion batteries, as well as problems associated with the development of polymer electrodes, are discussed. [ABSTRACT FROM AUTHOR]

Heteroatom modification represents one of the major areas of carbon materials' research in electrical energy storage. However, the influence of heteroatomic state evolution on electrochemical properties remains an elusive topic. Herein, thiophene‐2,5‐dicarboxylic acid is chemically activated to prepare O,S‐diatomic hybrid carbon material (OS–C). The heteroatoms and carbon matrix coexist in the form of CO/CO and CS/SS bonds, which introduce porous networks to the partially graphitized carbon skeleton and provide abundant active sites for better ion absorption. Moreover, the heteroatoms and carbon matrix are bridged to establish stable pseudocapacitive functional groups like quinoid unit and disulfide bonds, which can be electrochemically converted into benzenoid units and mercaptan anions through Faradaic reactions to further improve the reversible capacity. Combined with the detailed kinetic exploration and in situ investigation of the electrochemical impedance spectra, the energy storage mechanism for lithium/sodium is proposed in the following steps: Faradaic reactions at a higher potential range, energy storage at active sites, and ions intercalation on the graphitized parts in the low‐voltage states. Greatly, the electrode can store lithium up to the capacity of ≈700 mAh g−1, while also delivering ≈330 mAh g−1 of sodium storage, providing lifetimes in excess of thousands of cycles. [ABSTRACT FROM AUTHOR]

Room temperature sodium–sulfur batteries have emerged as promising candidate for application in energy storage. However, the electrodes are usually obtained through infusing elemental sulfur into various carbon sources, and the precipitation of insoluble and irreversible sulfide species on the surface of carbon and sodium readily leads to continuous capacity degradation. Here, a novel strategy is demonstrated to prepare a covalent sulfur–carbon complex (SC‐BDSA) with high covalent‐sulfur concentration (40.1%) that relies on SO3H (Benzenedisulfonic acid, BDSA) and SO42− as the sulfur source rather than elemental sulfur. Most of the sulfur is exists in the form of OS/CS bridge‐bonds (short/long‐chain) whose features ensure sufficient interfacial contact and maintain high ionic/electronic conductivities of the sulfur–carbon cathode. Meanwhile, the carbon mesopores resulting from the thermal‐treated salt bath can confine a certain amount of sulfur and localize the diffluent polysulfides. Furthermore, the CSxC bridges can be electrochemically broken at lower potential (<0.6 V vs Na/Na+) and then function as a capacity sponsor. And the R‐SO units can anchor the initially generated Sx2− to form insoluble surface‐bound intermediates. Thus SC‐BDSA exhibits a specific capacity of 696 mAh g−1 at 2500 mA g−1 and excellent cycling stability for 1000 cycles with 0.035% capacity decay per cycle. The covalent sulfur–carbon complex SC‐BDSA (S, 40.1%) with different chain lengths is prepared. The short‐chain bridges can be electrochemically broken at potential <0.6 V (Na/Na+) and then worked together with the long‐chain units as a capacity sponsor. The R‐SO parts anchor Sx2− to form insoluble surface‐bound intermediates, leading to a special capacity of ≈750 mAh g−1 over 200 cycles. [ABSTRACT FROM AUTHOR]

As a result of its high‐energy density, metal–selenides have demanded attention as a potential energy‐storage material. But they suffer from volume expansion, dissolved poly‐selenides and sluggish kinetics. Herein, utilizing' thermal selenization via the Kirkendall effect, microspheres of NiSe2 confined by carbon are successfully obtained from the self‐assembly of Ni‐precursor/PPy. The derived hierarchical hollow architecture increases the active defects for sodium storage, while the existing double N‐doped carbon layers significantly alleviate the volume swelling. As a result, it shows ultrafast rate capability, delivering a stable capacity of 374 mAh g−1, even after 3000 loops at 10.0 A g−1. These remarkable results may be ascribed to the NiOC bonds on the interface of NiSe2 and the carbon film, which leads to the faster transfer of ions, the effective trapping of poly‐selenide, and the highly reversible conversion reaction. The kinetic analysis of cyclic voltammetry (CV) demonstrates that the electrochemical process is mainly dominated by pseudocapacitive behaviors. Supported by the results of electrochemical impedance spectroscopy (EIS), it is confirmed that the solid–electrolyte interface films are reversibly formed/decomposed during cycling. Given this, this elaborate work might open up a potential avenue for the rational design of metal‐sulfur/selenide anodes for advanced battery systems. Hierarchial hollow‐structured NiSe2/N‐C with double carbon films are designed from the self‐assembled clew‐like Ni‐Pr by the Kirkendall effect. And it is found that incorporation of NiOC into the carbon layers enables tailoring of the interfacial traits, inducing the fascinating electrochemical behaviors. This elaborate work might open up a potential avenue for these rational TMDs anodes designs for advanced battery storage systems. [ABSTRACT FROM AUTHOR]