Design of an Ultra-Highly Stable Lithium-Sulfur Battery by Regulating the Redox Activity of Electrocatalyst and the Growth of Lithium Dendrite through Localized Electric Field.

Polysulfide shuttling and dendrite growth are two primary challenges that significantly limit the practical applications of lithium-sulfur batteries (LSBs). Herein, a three-in-one strategy for a separator based on a localized electrostatic field is demonstrated to simultaneously achieve shuttle inhibition of polysulfides, catalytic activation of the Li-S reaction, and dendrite-free plating of lithium ions. Specifically, an interlayer of polyacrylonitrile nanofiber (PNF) incorporating poled BaTiO (PBTO) particles and coating with a layer of MoS (PBTO@PNF-MoS) is developed on the PP separator.

Anionic Doping in Layered Transition Metal Chalcogenides for Robust Lithium-Sulfur Batteries.

Lithium-sulfur batteries (LSBs) are among the most promising next-generation energy storage technologies. However, a slow Li-S reaction kinetics at the LSB cathode limit their energy and power densities. To address these challenges, this study introduces an anionic-doped transition metal chalcogenide as an effective catalyst to accelerate the Li-S reaction.

Electronic Spin Alignment within Homologous NiS/NiSe Heterostructures to Promote Sulfur Redox Kinetics in Lithium-Sulfur Batteries.

The catalytic activation of the Li-S reaction is fundamental to maximize the capacity and stability of Li-S batteries (LSBs). Current research on Li-S catalysts mainly focuses on optimizing the energy levels to promote adsorption and catalytic conversion, while frequently overlooking the electronic spin state influence on charge transfer and orbital interactions. Here, hollow NiS/NiSe heterostructures encapsulated in a nitrogen-doped carbon matrix (NiS/NiSe@NC) are synthesized and used as a catalytic additive in sulfur cathodes.

Enhanced Electrochemical Hydrogenation of Benzaldehyde to Benzyl Alcohol on Pd@Ni-MOF by Modifying the Adsorption Configuration.

Electrocatalytic hydrogenation (ECH) approaches under ambient temperature and pressure offer significant potential advantages over thermal hydrogenation processes but require highly active and efficient hydrogenation electrocatalysts. The performance of such hydrogenation electrocatalysts strongly depends not only on the active phase but also on the architecture and surface chemistry of the support material. Herein, Pd nanoparticles supported on a nickel metal-organic framework (MOF), Ni-MOF-74, are prepared, and their activity toward the ECH of benzaldehyde (BZH) in a 3 M acetate (pH 5.

Identifying the Role of the Cationic Geometric Configuration in Spinel Catalysts for Polysulfide Conversion in Sodium-Sulfur Batteries.

An ABX spinel structure, with tetrahedral A and octahedral B sites, is a paradigmatic class of catalysts with several possible geometric configurations and numerous applications, including polysulfide conversion in metal-sulfur batteries. Nonetheless, the influence of the geometric configuration and composition on the mechanisms of catalysis and the precise manner in which spinel catalysts facilitate the conversion of polysulfides remain unknown. To enable controlled exposure of single active configurations, herein, Co and Co in CoO catalysts for sodium polysulfide conversion are in large part replaced by Fe and Fe, respectively, generating FeCoO and CoFeO.

Spin Effect to Promote Reaction Kinetics and Overall Performance of Lithium-Sulfur Batteries under External Magnetic Field.

Lithium-sulfur batteries (LSBs) are still limited by the shuttle of lithium polysulfides (LiPS) and the slow Li-S reaction. Herein, we demonstrate that when using cobalt sulfide as a catalytic additive, an external magnetic field generated by a permanent magnet can significantly improve the LiPS adsorption ability and the Li-S reaction kinetics. More specifically, the results show both experimentally and theoretically how an electron spin polarization of Co ions reduces electron repulsion and enhances the degree of orbital hybridization, thus resulting in LSBs with unprecedented performance and stability.

Metal Ion Cutting-Assisted Synthesis of Defect-Rich MoS Nanosheets for High-Rate and Ultrastable LiS Catalytic Deposition.

Active metal ions often show a strong cutting effect on the chemical bonds during high-temperature thermal processes. Herein, a one-pot metal ion cutting-assisted method was adopted to design defect-rich MoS nanosheet (NS)/ZnS nanoparticle (NP) heterojunction composites on carbon nanofiber skeletons (CNF@MoS/ZnS) via a simple Ar-ambience annealing. Results show that Zn ions capture S ions from MoS and form into ZnS NPs, and the MoS NSs lose S ions and become MoS ones.

Construction of all-carbon micro/nanoscale interconnected sulfur host for high-rate and ultra-stable lithium-sulfur batteries: Role of oxygen-containing functional groups.

Carbon nanotubes (CNTs) are often used to settle down the sluggish reaction kinetics in lithium-sulfur batteries (LSBs). However, the self-aggregation of CNTs often makes them fail to effectively inhibit the shuttling effect of soluble lithium polysulfide (LiPS) intermediates. Herein, a type of ultra-stable carbon micro/nano-scale interconnected "carbon cages" has been designed by incorporating polar acid-treated carbon fibers (ACF) into three-dimensional (3D) CNT frameworks during vacuum filtration processes.

Dissymmetric interface design of SnO/TiO side-by-side bi-component nanofibers as photoanodes for dye sensitized solar cells: Facilitated electron transport and enhanced carrier separation.

SnO/TiO type II heterojunctions are often introduced to enhance the separation efficiency of photogenerated carriers in photoelectrochemical electrodes, while most of these heterojunctions are of core-shell structure, which often limits the synergistic effect from the two components. In this work, dissymmetric SnO/TiO side-by-side bi-component nanofibers (SBNFs) with tunable composition ratios have been prepared by a novel needleless electrospinning technique with two V-shape connected conductive channels (V-channel electrospinning). Results show that this V-channel electrospinning technique is more stable, controllable and tunable for the large-scale preparation of SBNF materials compared to the traditional electrospinning using two side-by-side metal needles.

Role of nickel dopant on gas response and selectivity of electrospun indium oxide nanotubes.

It has been demonstrated that the incorporation of Ni into metal oxide-based gas sensors often enhances the sensing performance by increasing the catalytic and heterojunction effects. However, it remains unclear how these two effects work either individually or synergistically in gas sensing. Herein, a series of Ni-doped InO nanotubes (NIO NTs) with different doping concentrations were synthesized through a traditional electrospinning technique.

Energy storage mechanism in aqueous fiber-shaped Li-ion capacitors based on aligned hydrogenated-LiTiO nanowires.

It is reported that Li ions can contribute a lot to the capacitance of aqueous Li-ion capacitors (LICs), which might be due to the intercalation/de-intercalation processes of Li ions that also occur at the anodes. However the energy storage mechanism in the aqueous LIC system still requires further proof. In this work, a type of aqueous fiber-shaped LIC has been designed and developed using hydrogenated LiTiO (H-LTO) anodes, active carbon (AC) cathodes, and LiCl/PVA gel electrolytes with a double-helical structure.

Amide proton transfer magnetic resonance imaging of Alzheimer's disease at 3.0 Tesla: a preliminary study.

Background: Amide proton transfer (APT) imaging has recently emerged as an important contrast mechanism for magnetic resonance imaging (MRI) in the field of molecular and cellular imaging. The aim of this study was to evaluate the feasibility of APT imaging to detect cerebral abnormality in patients with Alzheimer's disease (AD) at 3.0 Tesla.

Analysis of the risk factors of postoperative respiratory dysfunction of type A aortic dissection and lung protection.

Aim: Retrospectively to analyze the risk factors of postoperative respiratory dysfunction (RD) in 196 patients with type A dissection operated on with cerebral perfusion and a lower body hypothermia circulatory arrest (HCA) and to investigate the method of the lung protection.

Methods: From January 2005 to April 2008, 196 patients with type A dissection underwent surgical repair with cerebral perfusion and HCA. There were 142 male patients and 54 female patients, with ages from 17 to 78 years.

SiC Nanorods Grown on Electrospun Nanofibers Using Tb as Catalyst: Fabrication, Characterization, and Photoluminescence Properties.

Well-crystallizedβ-SiC nanorods grown on electrospun nanofibers were synthesized by carbothermal reduction of Tb doped SiO2(SiO2:Tb) nanofibers at 1,250 °C. The as-synthesized SiC nanorods were 100-300 nm in diameter and 2-3 μm in length. Scanning electron microscopy (SEM) results suggested that the growth of the SiC nanorods should be governed by vapor-liquid-solid (VLS) mechanism with Tb metal as catalyst.