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Lithium–sulfur batteries (LSBs) are one of the main candidates for the next generation of energy storage systems. To improve the performance of LSBs, we herein propose the use of strained MoS2 (s-MoS2) as a catalytically active sulfur host. The introduction of strain in the MoS2 surface, which alters its atomic positions and expands the S–Mo–S angle, shifts the d-band center closer to the Fermi level and provides the surface with abundant and highly active catalytic sites; these enhance the catalyst's ability to adsorb lithium polysulfides (LiPS), accelerating its catalytic conversion and promoting lithium-ion transferability. Strain is generated through the synthesis of core–shell nanoparticles, using different metal sulfides as strain-inducing cores. s-MoS2 nanoparticles are supported on carbon nanofibers (CNF/s-MoS2), and the resulting electrodes are characterized by capacities of 1290 and 657 ​mAh g−1 ​at 0.2 and 5 ​C, respectively, with a 0.05% capacity decay rate per cycle at 8 ​C during 700 cycles. Overall, this work not only provides an ingenious and effective strategy to regulate LiPS adsorption and conversion through strain engineering, but also indicates a path toward the application of strain engineering in other energy storage and conversion fields.

Lithium–sulfur batteries (LSBs) with high energy density have the potential to replace current commercial lithium-ion batteries. However, the shuttle effect and the low conversion kinetics of lithium polysulfide (LiPS) remain the main challenges in the development of LSBs. In this study, a metal-free and simple-to-prepare carbon nitride with a high surface area and tubular morphology (CN-nt) is used as the sulfur host for LSBs. Due to its unique nanostructure and rich active sites, it not only effectively disperses the active sulfur material and anchors soluble polysulfide species, but it also promotes the nucleation process of Li2S, thus achieving fast and sustainable Li-S redox reactions. Experimental results show that the obtained S@CN-nt electrodes exhibit a high sulfur utilization of 1296.2 mAh g−1 at 0.1 C and a significant rate capability of 689.4 mAh g−1 at the high current rate of 3C. More importantly, the capacity retention reaches 87.7% after 500 cycles. This simple strategy of engineering unique carbon-based nanostructured hosts can inspire new ideas for developing cost-effective and metal-free host materials for sulfur-based batteries.

The document is a contents list for the Journal of Materials Chemistry A, which features articles and reviews on various topics related to materials science and engineering. The journal aims to connect the world with the chemical sciences and is published by The Royal Society of Chemistry. The latest issue covers a wide range of subjects, including materials for energy and sustainability, research on indium selenide crystals, smart interface heterojunctions for N2 reduction, and flame-retardant strategies for lithium-sulfur batteries. The papers provide valuable insights for researchers in the field and cover diverse areas such as microsupercapacitors, energy storage systems, gas detection, catalysis, battery applications, and thermoregulation. [Extracted from the article]

Lithium–sulfur batteries (LSBs) are feasible candidates for the next generation of energy storage devices, but the shuttle effect of lithium polysulfides (LiPSs) and the poor electrical conductivity of sulfur and lithium sulfides limit their application. Herein, a sulfur host based on nitrogen‐doped carbon (NC) coated with small amount of a transition metal telluride (TMT) catalyst is proposed to overcome these limitations. The properties of the sulfur redox catalyst are tuned by adjusting the anion vacancy concentration and engineering a ZnTe/CoTe2 heterostructures. Theoretical calculations and experimental data demonstrate that tellurium vacancies enhance the adsorption of LiPSs, while the formed TMT/TMT and TMT/C heterostructures as well as the overall architecture of the composite simultaneously provide high Li+ diffusion and fast electron transport. As a result, v‐ZnTe/CoTe2@NC/S sulfur cathodes show excellent initial capacities up to 1608 mA h g−1 at 0.1C and stable cycling with an average capacity decay rate of 0.022% per cycle at 1C during 500 cycles. Even at a high sulfur loading of 5.4 mg cm–2, a high capacity of 1273 mA h g−1 at 0.1C is retained, and when reducing the electrolyte to 7.5 µL mg−1, v‐ZnTe/CoTe2@NC/S still maintains a capacity of 890.8 mA h g−1 after 100 cycles at 0.1C. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) with high energy density have the potential to replace current commercial lithium-ion batteries. However, the shuttle effect and the low conversion kinetics of lithium polysulfide (LiPS) remain the main challenges in the development of LSBs. In this study, a metal-free and simple-to-prepare carbon nitride with a high surface area and tubular morphology (CN-nt) is used as the sulfur host for LSBs. Due to its unique nanostructure and rich active sites, it not only effectively disperses the active sulfur material and anchors soluble polysulfide species, but it also promotes the nucleation process of Li2S, thus achieving fast and sustainable Li-S redox reactions. Experimental results show that the obtained S@CN-nt electrodes exhibit a high sulfur utilization of 1296.2 mAh g−1 at 0.1 C and a significant rate capability of 689.4 mAh g−1 at the high current rate of 3C. More importantly, the capacity retention reaches 87.7% after 500 cycles. This simple strategy of engineering unique carbon-based nanostructured hosts can inspire new ideas for developing cost-effective and metal-free host materials for sulfur-based batteries. [ABSTRACT FROM AUTHOR]

A functional electrolyte containing 3,3‐diethylene di‐sulfite (DES) additive is developed to improve the performances of LiNi0.8Co0.1Mn0.1O2 (NCM811)/graphite batteries, especially at high charging cut‐off voltage of 4.50 V. It is indicated that under the conventional conditions of 25 °C and 1 C after 300 cycles in the voltage range of 2.75–4.30 V, the batteries with 0.25 % DES can increase the maximum capacity retention from 66.61 % to 77.25 % initial discharge capacity compared with the batteries without DES. Especially, when the charge cut‐off voltage is increased to 4.50 V, the batteries with 1 % DES exhibit higher capacity retention (82.53 %) after 150 cycles than the batteries without DES (51.19 %). The electrochemical tests and spectroscopic characterization show that this functional DES electrolyte additive well regulates the anode and cathode interfaces with more stabilized films and smaller impedance, which promotes the interfacial extraction and insertion of Li+. In addition, the interfacial film can inhibit the dissolution of the transition metal element Ni from the cathode and protect the structure stability of NCM811 material. The electrolyte containing DES additive reveals promising prospects in the application of NCM811/graphite batteries. [ABSTRACT FROM AUTHOR]

As the most promising cathode material in new energy resources, LiNi0.5Mn1.5O4 (LNMO) are widely researched due to its high platform, low cost, and environment‐friendliness, when they are assembled with graphite into battery which can lead to a faster capacity decay because of unstable solid–liquid interface. This work is devoted to stabilize electrolyte and protect interface of LNMO/graphite full battery by adding multifunctional additive, tributyl phosphate (TBP). Theory calculation which exhibits disconnection of TBP can participate in the reaction to form a uniform and dense cathode electrolyte interface film (8–10 nm) and solid electrolyte interface film around 15 nm on both electrodes, more importantly, the existence of phosphoric acid functional group can hinder the attack of hydrofluoric acid and protect electrode film. Besides, comparing with its homolog, the high‐voltage LiNi0.5Mn1.5O4/graphite battery with 1% TBP shows a preponderant discharged capacity retention of 77.8% after 150 cycles, while the blank is only 66%, this work provides a direction for electrolyte additives' selection at high voltage and has far‐reaching significance for the application of phosphate ester materials. [ABSTRACT FROM AUTHOR]