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The shuttle effect of lithium polysulfides (LiPSs) in lithium-sulfur batteries (LSBs) has been hampered their commercialization. Metal oxides as separator modifications can suppress the shuttle effect. Since there is no direct electron transport between metal oxides and LiPSs, absorbed LiPSs should be diffused from the surface of metal oxides to the carbon matrix to go through redox reactions. If diffusivity of LiPSs from metal oxides surface to carbon substrate is poor, it would hinder the redox reactions of LiPSs. Nevertheless, researchers tend to focus on the adsorption and overlook the diffusion of LiPSs. Herein, same morphology and different crystal phase of TiO2 nanosheets grown on carbon nanotubes (CNTs@TiO2-bronze and CNTs@TiO2-anatase) have been designed via a simple approach. Compared with CNTs and CNTs@TiO2-anatase composites, the battery with CNTs@TiO2-bronze modified separator delivers higher specific capacities and stronger cycling stability, especially at high current rates (∼ 472 mAh·g−1 at 2.0 C after 1,000 cycles). Adsorption tests, density functional theory calculations and electrochemical performance evaluations indicate that suitable diffusion and adsorption for LiPSs on the CNTs@TiO2-B surface can effectively capture LiPSs and promote the redox reaction, leading to the superior cycling performances. [ABSTRACT FROM AUTHOR]

Semiconductor combination is one of the most common strategies to obtain high-efficiency photocatalysts; however, the effect mechanism of composition ratio on micro-structure and photocatalytic activity is remaining unclear. In this study, a case of g-C3N4 quantum dots@SnS2 (CNQDn@SnS2) heterojunction with different ratio of CNQD is used to uncover the origin of optimum and excess composition for photocatalysts. Research on the functional mechanism of the optimum composition shows that 0.8 wt.% CNQD are completely attached to the non-(001) facets of SnS2, which benefits the formation of type-II heterojunction, resulting in an optimal pollutant degradation and mineralization efficiency. For the excess composition, both experiments and theoretical calculations confirm that excess CNQD (the part exceeding of 0.8 wt.%) located on the (001) facet of SnS2, leading to the type-I band alignment of this heterojunction, which severely restricts the separation of photo-induced charge carriers, and thus reduces their lifetime. This work makes the functional mechanism of composition ratio on micro-structure and photocatalytic activity clearer. Related research results provide a new insight into semiconductor combination study and take an important step toward the rational design of highly active photocatalysts. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) has been widely investigated as the electrode material for lithium ion batteries (LIBs), due to its low cost, small volume expansion, and high environmental friendliness. However, the fading capacity and short cycle life during the cycling process lead to poor cycling performance. Herein, multilayer TiO2 nanobelts with a high specific surface area and with many pores between nanoparticles are constructed via a simple and large-scale approach. Benefiting from the multilayer nanobelt structure, as-prepared TiO2 nanobelts deliver a high reversible capacity, strong cycling stability, and ultra-long cycle life (~185 mAh g−1 at 500 mA g−1 after 500 cycles) as electrode materials for LIBs. Benefiting from a multilayer nanobelt structure, as-prepared TiO2 nanobelts deliver a high reversible capacity, strong cycling stability, and ultra-long cycle life (~185 mAh g−1 at 500 mA g−1 after 500 cycles) as electrode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

A facile strategy was developed to prepare interlayer-expanded MoS2/graphene composites through a one-step hydrothermal reaction method. MoS2 nanosheets with several-layer thickness were observed to uniformly grow on the surface of graphene sheets. And the interlayer spacing of MoS2 in the composites was determined to expand to 0.95 nm by ammonium ions intercalation. The MoS2/graphene composites show excellent lithium storage performance as anode materials for Li-ion batteries. Through gathering advantages including expanded interlayers, several-layer thickness, and composited graphene, the composites exhibit reversible capacity of 1030.6 mAh g−1 at the current density of 100 mA g−1 and still retain a high specific capacity of 725.7 mAh g−1 at a higher current density of 1000 mA g−1 after 50 cycles. [ABSTRACT FROM AUTHOR]

Although the synthesis of mesoporous materials is well established, the preparation of TiO2 fiber bundles with mesostructures, highly crystalline walls, and good thermal stability on the RGO nanosheets remains a challenge. Herein, a low-cost and environmentally friendly hydrothermal route for the synthesis of RGO nanosheet-supported anatase TiO2 fiber bundles with dense mesostructures is used. These mesostructured TiO2-RGO materials are used for investigation of Li-ion insertion properties, which show a reversible capacity of 235 mA h g−1 at 200 mA g−1 and 150 mA h g−1 at 1000 mA g−1 after 1000 cycles. The higher specific surface area of the new mesostructures and high conductive substrate (RGO nanosheets) result in excellent lithium storage performance, high-rate performance, and strong cycling stability of the TiO2-RGO composites. [ABSTRACT FROM AUTHOR]

Mesoporous wall-structured TiO2 on reduced graphene oxide (RGO) nanosheets were successfully fabricated through a simple hydrothermal process without any surfactants and annealed at 400 °C for 2 h under argon. The obtained mesoporous structured TiO2-RGO composites had a high surface area (99 0307 m2 g−1) and exhibited excellent electrochemical cycling (a reversible capacity of 260 mAh g−1 at 1.2 C and 180 mAh g−1 at 5 C after 400 cycles), demonstrating it to be a promising method for the development of high-performance Li-ion batteries. [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 TiO 2 (B) nanosheets with oxygen vacancies (OVs) grown in situ on MXenes layers (N-TiO 2- x (B)-MXenes) as multifunctional interlayers are designed. The N-TiO 2- 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-TiO 2- 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-TiO 2- 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., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

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.

Defect engineering is recognized as an effective route to obtaining highly active photocatalytic materials. However, the current understanding of the role of defects in photocatalysts mainly comes from their independent functional analysis, ignoring the synergy between defects and the chemical environment, especially with crystal facets. Herein, oxygen vacancy (V O )-rich TiO 2 nanostructures with different dominant exposed facets were prepared, and the microstructural changes induced by the synergy between the V O and facet effect and the performance difference of photocatalytic O 2 activation were explored. The results showed that the combination of high concentration V O and the {101} facet is more conducive to improving the photocatalytic performance of TiO 2 , which is significantly superior to the combination of low concentration V O and the {101} facet as well as the combination of high concentration V O and the {001} facet. The experimental and theoretical results clarified the dependence of each stage of photocatalysis on two factors. Specifically, V O plays a more significant role in energy band regulation, improving the dynamic behavior of photogenerated charges and enhancing the adsorption and activation of O 2 , while the facet effect made more contributions to reducing the thermodynamic energy barrier of ROS formation and conversion. The excellent ability of O 2 activation enables T101-V O to show potential application characteristics in the removal of RhB and bacterial disinfection. This work established a link between defect and facet effects, providing new insights into understanding defect function in photocatalysts.

Lithium-sulfur batteries (LSBs) are receiving extensive attention because of their high theoretical energy density. However, practical applications of LSBs are still hindered by their rapid capacity decay and short cycle life, especially at high rates. Herein, a highly N-doped (≈13.42 at %) hierarchical carbon sponge (HNCS) with strong chemical adsorption for lithium polysulfide is fabricated through a simple sol-gel route followed by carbonization. Upon using the HNCS as the sulfur host material in the cathode and an HNCS-coated separator, the battery delivers an excellent cycling stability with high specific capacities of 424 and 326 mA h g -1 and low capacity fading rates of 0.033 % and 0.030 % per cycle after 1000 cycles under high rates of 5 and 10 C, respectively, which are superior to those of other reported carbonaceous materials. These impressive cycling performances indicate that such a battery could promote the practical application prospects of LSBs., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Although the synthesis of mesoporous materials is well established, the preparation of TiO2 fiber bundles with mesostructures, highly crystalline walls, and good thermal stability on the RGO nanosheets remains a challenge. Herein, a low-cost and environmentally friendly hydrothermal route for the synthesis of RGO nanosheet-supported anatase TiO2 fiber bundles with dense mesostructures is used. These mesostructured TiO2 -RGO materials are used for investigation of Li-ion insertion properties, which show a reversible capacity of 235 mA h g(-1) at 200 mA g(-1) and 150 mA h g(-1) at 1000 mA g(-1) after 1000 cycles. The higher specific surface area of the new mesostructures and high conductive substrate (RGO nanosheets) result in excellent lithium storage performance, high-rate performance, and strong cycling stability of the TiO2 -RGO composites., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Mesoporous wall-structured TiO2 on reduced graphene oxide (RGO) nanosheets were successfully fabricated through a simple hydrothermal process without any surfactants and annealed at 400 °C for 2 h under argon. The obtained mesoporous structured TiO2 -RGO composites had a high surface area (99 0307 m(2)  g(-1)) and exhibited excellent electrochemical cycling (a reversible capacity of 260 mAh g(-1) at 1.2 C and 180 mAh g(-1) at 5 C after 400 cycles), demonstrating it to be a promising method for the development of high-performance Li-ion batteries., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A simple and steerable method was adopted to synthesize well-distributed rutile TiO2 nanobundles on reduced graphene oxides through two-step hydrothermal methods. The rutile TiO2-RGO composites were used as the anode materials in lithium ion batteries for investigation, which had an original morphology and a reversible capacity of 300 mA h g(-1) at 0.6 C and 200 mA h g(-1) at 1.2 C after 500 cycles.