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Constructing hierarchical superstructures through one‐step bottom‐up synthesis poses significant challenges due to strong interactions between additives and micelles, which hinders the formation of heterogeneous configurations. Here, we propose a high‐temperature‐mediated method to weaken these interactions and manipulate the thermal instability of micellar templates. This approach successfully synthesizes hierarchical superstructures that combine a carbonaceous nanosheet substrate with polyoxometalate (POM)‐induced, highly ordered discontinuous nanodots in a single preparation step. The surface nanodots have a diameter of approximately 19 nm and are spaced about 32 nm apart. Besides, the nanodots with various arrangements can be generated by simply adjusting the amount of POM. Importantly, the superstructure features more exposed POM catalytic sites than conventional carbonaceous hybrids lacking surface architectures, resulting in excellent electrochemical performance in lithium‐sulfur (Li−S) batteries. This high‐temperature‐mediated approach offers new insights for designing hierarchical superstructures and functional materials with enhanced activities. [ABSTRACT FROM AUTHOR]

Organosulfur compounds are regarded as a kind of prospective cathode materials for lithium batteries due to their high theoretical specific capacity. However, they still suffer from the issues of sluggish redox kinetics and low utilization. The rational design of the cathode host for effectively confining active materials and accelerating the sluggish sulfur kinetics is an effective strategy. Herein, the study synthesizes an atomic‐scale single‐atom cobalt catalyst and interweave it with CNTs to fabricate an ideal host material (donated as CoSANC@CNTs) for the cathode in Li–PTS batteries. Electrochemical measurements reveal that CoSANC not only efficiently accelerates the redox kinetics in the whole reaction process but also shows excellent adsorption capacity, which is corroborated by the theoretical calculation results as well. As excepted, the Li–PTS battery equipped with CoSANC@CNTs electrode delivers an outstanding long cycling stability with a high initial specific capacity of 550.2 mAh g−1 and a slow capacity decay rate of 0.05% per cycle over 700 cycles at 1 C. Even under a high PTS loading of 8.6 mg cm−2, the PTS/CoSANC@CNTs cathode is still maintained with an excellent capacity retention of 91.1% at 0.1 C after 50 cycles. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of lithium‐sulfur (Li−S) batteries severely impedes the application in extreme conditions. Bridging the sulfur cathode and lithium anode, the electrolyte plays a crucial role in regulating kinetic behaviors of Li−S batteries. Herein, we report a multifunctional electrolyte additive of phenyl selenium bromide (PhSeBr) to simultaneously exert positive influences on both electrodes and the electrolyte. For the cathode, an ideal conversion routine with lower energy barrier can be attained by the redox mediator and homogeneous catalyst derived from PhSeBr, thus improving the reaction kinetics and utilization of sulfur. Meanwhile, the presence of Se−Br bond helps to reconstruct a loose solvation sheath of lithium ions and a robust bilayer SEI with excellent ionic conductivity, which contributes to reducing the de‐solvation energy and simultaneously enhancing the interfacial kinetics. The Li−S battery with PhSeBr displays superior long cycling stability with a reversible capacity of 1164.7 mAh g−1 after 300 cycles at 0.5 C rate. And the pouch cell exhibits a maximum capacity of 845.3 mAh and a capacity retention of 94.8 % after 50 cycles. Excellent electrochemical properties are also obtained in extreme conditions of high sulfur loadings and low temperature of −20 °C. This work demonstrates the versatility and practicability of the special additive, striking out an efficient but simple method to design advanced Li−S batteries. [ABSTRACT FROM AUTHOR]

Regioselective benzanilide bromination that generates either regioisomer from the same starting material is desirable. Herein, we develop switchable site-selective C(sp2)-H bromination by promoter regulation. This protocol leads to regiodivergent brominated benzanilide starting from the single substrate via selection of promoters. The protocol demonstrates excellent regioselectivity and good tolerance of functional groups with high yields. The utility effectiveness of this method has been well exemplified in the late-stage modification of biologically important molecules. [ABSTRACT FROM AUTHOR]

Enhancing the selectivity of alpha 2 -adrenoceptor (α 2A -AR) agonists remains an unresolved issue. Herein, we reported the design of an α 2A -AR agonist using the conformation constraint method, beginning with medetomidine. The structure-activity relationship indicated that the 8-substituent of chromane derivatives exerted the most pronounced effect on α 2A -AR agonistic activity. Compounds A9 and B9 were identified as the most promising, exhibiting EC 50 values of 0.78 and 0.23 nM, respectively. Their selectivity indexes surpassed dexmedetomidine (DMED) by 10-80 fold. In vivo studies demonstrated that both A9 and B9 dose-dependently increased the loss of righting reflex in mice, with ED 50 values of 1.54 and 0.138 mg/kg, respectively. Binding mode calculations and mutation studies suggested the indispensability of the hydrogen bond between ASP128 3.32 and α 2A -AR agonist. In particular, A9 and B9 showed no dual reverse pharmacological effect, a characteristic exhibited by DMED in α 2A -AR activation.

Achieving high energy density and long cycle life in realistic batteries is still an unmet need, which has triggered research into the discoveries of new electrode materials as well as new storage mechanisms. As a kind of new cathode materials for rechargeable lithium batteries, organosulfide compounds R-S n -R (n = 3-6) based on conversion chemistries of SS bonds have many advantages and promising prospects; however, poor electric/ionic conductivity and sluggish redox kinetics is a major hinder for their applications. Here an organic-inorganic hybrid cathode by introducing 1T MoS 2 grown on reduced graphene oxide to hybridize with phenyl tetrasulfide (Ph-S 4 -Ph, theoretical specific capacity 570 mAh g -1 ), enhancing the battery performance is reported. This includes the improved charge transfer, stable long cycles, and close-to-practical energy density in coin cells and pouch cells, which also show high mass loadings and contents, and low electrolyte dependence. Furthermore, the dynamic 1T-2H mixed-phase during the charge/discharge is revealed to be critical for the improved performance. This study proves the hybrid nanomaterials as a promising solution to address the challenges facing lithium-organosulfide batteries., (© 2021 Wiley-VCH GmbH.)