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Lithium‐sulfur batteries (LSBs) have become one of the most powerful candidates for next‐generation battery technologies due to their high theoretical energy density and low cost. However, the notorious shuttle effect of soluble lithium polysulfides (LiPSs) and sluggish conversion reaction kinetics cause low sulfur utilization and inferior cycle life. Rational catalyst design on hierarchical pore structures and composition optimization is highly desired to realize synergetic enrichment, accommodation, and catalytic redox capacity of sulfur species. In this consideration, the hollow and porous N‐doped carbon framework is prepared, in which Co nanoparticles (NPs) are evenly embedded (denoted as Co‐HMCF) to modulate electron cloud density of carbons. Electrochemical tests and density functional theory (DFT) calculations demonstrate that Co‐HMCF could simultaneously deliver superior catalytic activity in accelerating LiPSs conversion as well as Li2S nucleation/decomposition to improve overall sulfur redox kinetics. Consequently, the Co‐HMCF interlayer significantly improves the battery performance, including high discharge capacity output (1538 mAh g−1 at 0.2 C), stable long‐term cycle (0.047% capacity decay per cycle for 800 cycles at 1.0 C), and exceptional rate capacity (582 mAh g−1 at 5.0 C). [ABSTRACT FROM AUTHOR]

Practical application of lithium–sulfur (Li–S) batteries is severely impeded by the random shuttling of soluble lithium polysulfides (LiPSs), sluggish sulfur redox kinetics, and uncontrollable growth of lithium dendrites, particularly under high sulfur loading and lean electrolyte conditions. Here, nitrogen‐doped bronze‐phase TiO2(B) nanosheets with oxygen vacancies (OVs) grown in situ on MXenes layers (N‐TiO2−x(B)‐MXenes) as multifunctional interlayers are designed. The N‐TiO2−x(B)‐MXenes show reduced bandgap of 1.10 eV and high LiPSs adsorption‐conversion‐nucleation‐decomposition efficiency, leading to remarkably enhanced sulfur redox kinetics. Moreover, they also have lithiophilic nature that can effectively suppress dendrites growth. The cell based on the N‐TiO2−x(B)‐MXenes interlayer under sulfur loading of 2.5 mg cm−2 delivers superior cycling performance with a high specific capacity of 690.7 mAh g−1 over 600 cycles at 1.0 C. It still has a notable areal capacity of 6.15 mAh cm−2 after 50 cycles even under a high sulfur loading of 7.2 mg cm−2 and a low electrolyte‐to‐sulfur (E/S) ratio of 6.4 µL mg−1. The Li‐symmetrical battery with the N‐TiO2−x(B)‐MXenes interlayer showcases a low over‐potential fluctuation with 21.0 mV throughout continuous lithium plating/stripping for 1000 h. This work offers valuable insights into the manipulation of defects and heterostructures to achieve high‐energy Li–S batteries. [ABSTRACT FROM AUTHOR]

The inevitable shuttling and slow redox kinetics of lithium polysulfides (LiPSs) as well as the uncontrolled growth of Li dendrites have strongly limited the practical applications of lithium‐sulfur batteries (LSBs). To address these issues, we have innovatively constructed the carbon nanotubes (CNTs) encapsulated Co nanoparticles in situ grown on TiN‐MXene nanosheets, denoted as TiN‐MXene‐Co@CNTs, which could serve simultaneously as both sulfur/Li host to kill "three birds with one stone" to (1) efficiently capture soluble LiPSs and expedite their redox conversion, (2) accelerate nucleation/decomposition of solid Li2S, and (3) induce homogeneous Li deposition. Benefiting from the synergistic effects, the TiN‐MXene‐Co@CNTs/S cathode with a sulfur loading of 2.5 mg cm−2 could show a high reversible specific capacity of 1129.1 mAh g−1 after 100 cycles at 0.1 C, and ultralong cycle life over 1000 cycles at 1.0 C. More importantly, it even achieves a high areal capacity of 6.3 mAh cm−2 after 50 cycles under a sulfur loading as high as 8.9 mg cm−2 and a low E/S ratio of 5.0 μL mg−1. Besides, TiN‐MXene‐Co@CNTs as Li host could deliver a stable Li plating/striping behavior over 1000 h. [ABSTRACT FROM AUTHOR]

For practical lithium–sulfur batteries (LSBs), the high sulfur loading and lean‐electrolyte are necessary conditions to achieve the high energy density. However, such extreme conditions will cause serious battery performance fading, due to the uncontrolled deposition of Li2S and lithium dendrite growth. Herein, the tiny Co nanoparticles embedded N‐doped carbon@Co9S8 core–shell material (CoNC@Co9S8NC) is designed to address these challenges. The Co9S8NC‐shell effectively captures lithium polysulfides (LiPSs) and electrolyte, and suppresses the lithium dendrite growth. The CoNC‐core not only improves electronic conductivity, but also promotes Li+ diffusion as well as accelerates Li2S deposition/decomposition. Consequently, the cell with CoNC@Co9S8NC modified separator delivers a high specific capacity of 700 mAh g−1 with a low‐capacity decay rate of 0.035% per cycle at 1.0 C after 750 cycles under a sulfur loading of 3.2 mg cm−2 and a E/S ratio of 12 µL mg−1, and a high initial areal capacity of 9.6 mAh cm−2 under a high sulfur loading of 8.8 mg cm−2 and a low E/S ratio of 4.5 µL mg−1. Besides, the CoNC@Co9S8NC exhibits an ultralow overpotential fluctuation of 11 mV at a current density of 0.5 mA cm–2 after 1000 h during a continuous Li plating/striping process. [ABSTRACT FROM AUTHOR]

Facial nerve schwannoma (FNS) is a benign, slow-growing schwannoma that originates from Schwann cells. Facial nerve schwannoma is the most common tumor of the facial nerve but rare and only accounts for 0.15% to 0.8% of intracranial neurinomas. It may be manifested as asymmetric hearing loss, facial palsy, and hemifacial spasm. A 56-year-old woman was transferred to our department, because of pain behind the right ear and spasm of the right lateral muscle for more than 2 years and pulsatile tinnitus for half a year. Based on the preoperative medical history, physical signs, and auxiliary examination, it was diagnosed with jugular foramen (JF) space-occupying lesion. We removed the tumor through the infratemporal fossa type A approach and found that the tumor originated from the facial nerve. After the tumor resection, sural nerve transplantation was performed. The patient demonstrated postoperative facial palsy (House-Brackman grade VI) and was smoothly discharged after good recovery. Facial nerve schwannoma rarely invades the JF, and the most common tumor in the JF is the glomus jugular tumor, followed by the posterior cranial schwannoma. They have common symptoms, making it difficult to obtain a correct diagnosis. Clinical data, medical history, and auxiliary examinations should be carefully analyzed to avoid misdiagnosis or mistreatment. Infratemporal fossa type A approach is an effective method for treating FNS of JF. [ABSTRACT FROM AUTHOR]

The theoretically high‐energy‐density lithium–sulfur batteries (LSBs) are seriously limited by the disadvantages including the shuttle effect of soluble lithium polysulfides (LiPSs) and the sluggish sulfur redox kinetics, especially for the most difficult solid–solid conversion of Li2S2 to Li2S. Herein, a multifunctional catalytic interlayer to improve the performance of LSBs is tried to introduce, in which Fe1–xS/Fe3C nanoparticles are embedded in the N/S dual‐doped carbon network (NSC) composed by nanosheets and nanotubes (the final product is named as FeSC@NSC). The well‐designed 3D NSC network endows the interlayer with a satisfactory LiPSs capture‐catalytic ability, thus ensuring fast redox reaction kinetics and suppressing LiPSs shuttling. The density functional theory calculations disclose the catalytic mechanisms that FeSC@NSC greatly improves the liquid–solid (LiPSs to Li2S2) conversion and unexpectedly the solid–solid (Li2S2 to Li2S) one. As a result, the LSBs based on the FeSC@NSC interlayer can achieve a high specific capacity of 1118 mAh g−1 at a current density of 0.2 C, and a relatively stable capacity of 415 mAh g−1 at a large current density of 2.0 C after 700 cycles as well as superior rate performance. [ABSTRACT FROM AUTHOR]

Defect engineering is recognized as an effective route to obtain highly active photocatalytic materials. However, the current understanding of defects is mainly limited to isolated atomic vacancy defects, ignoring the exploration of the functions of multivariate defects formed by the deletion of several adjacent atoms in photocatalytic system. Here, we prepared SnS2 nanostructures with the same morphology but different dominant defects, and by testing their photocatalytic performance, it was found that the multivariate defects can significantly improve the photocatalytic performance than isolated S vacancies. Combining experiments and theoretical calculations, we confirmed that the promotion of multivariate defects, especially "S-Sn-S" vacancy associates, on the photocatalytic performance is reflected in many aspects, such as the regulation of the energy band structure, the improvement of the charge separation efficiency, and the promotion of the adsorption and activation of guest molecules. SnS2 with "S-Sn-S" vacancy associates exhibits excellent photocatalytic water purification ability. Under the induction of "S-Sn-S" vacancy associates, phenol was thoroughly photocatalytically decomposed, further confirming its excellent functionality. This work not only provides new insights into identifying advantage defects in the catalyst structure, but also offers new ideas for constructing highly active photocatalysts based on defect engineering. [ABSTRACT FROM AUTHOR]