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The realization of a low negative/positive capacity (N/P) ratio is essential for attaining high energy density in lithium‐sulfur batteries (LSBs). However, it has been challenging to maintain the stability of the Li metal anode at low N/P ratios. Herein, it is revealed that the corrosion of the Cu current collector by dissolved intermediates of polysulfides ‐a largely overlooked perspective‐ significantly contributes to the instability of Li metal anode at low N/P ratios. The reduced Li/Li+ redox rates on the corroded Cu surface result in uneven and porous Li deposits that severely deteriorate cycling stability. To address this issue, an anti‐corrosion alloy coating is developed to passivate the Cu surface against polysulfides. LSBs with passivated current collectors at a low N/P ratio (1.5) and lean electrolyte (5 µL mgs −1) show a ten fold extension in cycle and calendar life. This study not only provides the initial evidence of the impact of Cu corrosion on the failure mechanism of low N/P ratio LSBs but also proposes a practical yet effective strategy to stabilize high‐energy‐density LSBs. [ABSTRACT FROM AUTHOR]

Despite concerns regarding safety, economics, and the environment, lithium-ion batteries (LIBs) are considerably utilized on account of their low energy density and capacity. Li–sulfur (Li–S) batteries have become a promising substitute for LIBs. Here, we first compared both systems in their cons and pros and analyzed the leading countries and companies in Li–S research are assessed through the utilization of an academic database. The scope of our research includes performance-enhancing design elements, cathode components, and binder materials. Synthetic and natural binders are trialed in an effort to enhance Li–S performance. Understanding the fundamental mechanisms enables the development of durable cathodes and binders. To overcome obstacles such as polysulfide adsorption, shuttle effect, and ion transport limitations, conducting polymers, metal/metal oxides, carbon-based compounds, MOFs, and Mxenes are investigated as potential cathode materials. In addition to pore characteristics and active polar sites, the efficacy of a battery is influenced by the anode surface geometry and heteroatom doping. Our review indicates that binders and sulfur/host composites must be meticulously chosen for Li–S battery cathode materials. This research advances energy storage technology by establishing the foundation for economically viable lithium–sulfur batteries with superior performance. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are a promising option for energy storage due to their theoretical high energy density and the use of abundant, low-cost sulfur cathodes. Nevertheless, several obstacles remain, including the dissolution of lithium polysulfides (LiPS) into the electrolyte and a restricted operational temperature range. This manuscript presents a promising approach to addressing these challenges. The manuscript describes a straightforward and scalable in situ thermal polymerization method for synthesizing a quasi-solid-state electrolyte (QSE) by gelling pentaerythritol tetraacrylate (PETEA), azobisisobutyronitrile (AIBN), and a dual salt lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium nitrate (LiNO3)-based liquid electrolyte. The resulting freestanding quasi-solid-state electrolyte (QSE) effectively inhibits the polysulfide shuttle effect across a wider temperature range of −25 °C to 45 °C. The electrolyte's ability to prevent LiPS migration and cluster formation has been corroborated by scanning electron microscopy (SEM) and Raman spectroscopy analyses. The optimized QSE composition appears to act as a physical barrier, thereby significantly improving battery performance. Notably, the capacity retention has been demonstrated to reach 95% after 100 cycles at a 2C rate. Furthermore, the simple and scalable synthesis process paves the way for the potential commercialization of this technology. [ABSTRACT FROM AUTHOR]

Traditionally, garlic has a valuable role in preventing and reducing the incidence of many diseases and pathophysiological disorders. Consequently, some researchers have focused on the beneficial cardiovascular properties of diallyl trisulfide (DATS), the most potent polysulfide isolated from garlic. Therefore, in this review, we collected the available data on DATS, its biochemical synthesis, metabolism and pharmacokinetics, and gathered the current knowledge and the role of DATS in cardiovascular diseases. Overall, this review summarizes the cardioprotective effects of DATS and brings together all previous findings on its protective molecular mechanisms, which are mainly based on the potent anti-apoptotic, anti-inflammatory, and antioxidant potential of this polysulfide. Our review is an important cornerstone for further basic and clinical research on DATS as a new therapeutic agent for the treatment of numerous heart diseases. [ABSTRACT FROM AUTHOR]

Trisulfide unit is widely found in natural products and has garnered attention due to the unique pharmacological and physiochemical properties. However, despite limited progress, widely applicable approaches for constructing unsymmetrical trisulfides have so far remain scarce. In this work, an easy‐to‐prepare, solid‐state and scalable reagent, S‐substituted sulphenylthiosulphate, has been developed for the divergent synthesis of unsymmetrical trisulfides. Alkyl electrophile substrates, including bromides, chlorides, iodides and tosylates, with diverse substituents are smoothly converted to the corresponding trisulfides with S‐substituted sulphenylthiosulphates and thiourea as another sulfur source. Furthermore, the late‐stage modification of drug molecules was successfully achieved through this method. [ABSTRACT FROM AUTHOR]

Aspect ratio of OMCs is tuned, and correlations between aspect ratio of OMCs and battery performance of S@OMCs are systematically studied. Evolution of sulfur species in OMCs is revealed by SAXS, providing guidelines for optimizing sulfur cathodes. [Display omitted] Tailoring porous host materials, as an effective strategy for storing sulfur and restraining the shuttling of soluble polysulfides in electrolyte, is crucial in the design of high-performance lithium-sulfur (Li-S) batteries. However, for the widely studied conductive hosts such as mesoporous carbon, how the aspect ratio affects the confining ability to polysulfides, ion diffusion as well as the performances of Li-S batteries has been rarely studied. Herein, ordered mesoporous carbon (OMC) is chosen as a proof-of-concept prototype of sulfur host, and its aspect ratio is tuned from over ∼ 2 down to below ∼ 1.2 by using ordered mesoporous silica hard templates with variable length/width scales. The correlation between the aspect ratio of OMCs and the electrochemical performances of the corresponding sulfur-carbon cathodes are systematically studied with combined electrochemical measurements and microscopic characterizations. Moreover, the evolution of sulfur species in OMCs at different discharge states is scrutinized by small-angle X-ray scattering. This study gives insight into the aspect ratio effects of mesoporous host on battery performances of sulfur cathodes, providing guidelines for designing porous host materials for high-energy sulfur cathodes. [ABSTRACT FROM AUTHOR]

This study included the modification of asphalt using sulfur waste (foam) resulting from the purification of sulfur from the Al-Mishraq field through a chemical oxidation method. In addition, it utilized nano sulfur prepared from these wastes in the modification of asphalt. The study initiated with a comprehensive analysis of foam composition and employed various diagnostic techniques. It then proceeded to prepare calcium polysulfide, sodium polysulfide and potassium polysulfide from the foam, followed by the preparation of nano_sulfur from these salts. The sulfur's nano-sized particles were characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) to determine sulfur content, and the particle size range was (83.40nm), (45.13nm) and (38.51nm). The prepared nano-sulfur was used to modify the properties of Iraqi asphalt. The original and modified asphalt's rheological properties were determined by measuring properties such as Ductility, softening point, penetration, penetration index, Marshall stability, chemical immersion, and aging. The modified asphalt showed rheological properties that qualified it for use in paving operations, especially in terms of resistance to acid rain and stability. [ABSTRACT FROM AUTHOR]

Introduction. A method for protecting concrete and aerated concrete by treatment with a calcium polysulfide-based solution is considered. The solution penetrates into the pores of the materials and, after drying, forms a water-repellent nanoscale layer, protecting the material from water penetration. This ultra-thin layer is formed as a result of the destruction of calcium polysulfide molecules while drying the impregnating solution and gives the material hydrophobic properties. The paper presents research results of the properties and composition of the forming protective layer and its effect on water penetration into the materials. Materials and methods. In the article authors present data on water penetration into the studied concrete and aerated concrete samples, the size and composition of the hydrophobic agent using laser and X-ray diffraction, ultraviolet spectroscopy, as well as using visual research methods, including electron microscopy. Results. It has been revealed that the hydrophobic surface is formed from a mixture of sulfur and calcium carbonate. It is shown that concrete and aerated concrete impregnated with a calcium polysulfide-based solution acquires pronounced water-repellent properties, expressed in contact angles corresponding to superhydrophobic surfaces. The presence of sulfur was established by ultraviolet spectroscopy, and force microscopy showed the formation of nanocomposite particles from sulfur and calcium compounds. X-ray phase analysis showed that the protective layer deposited on the surface of the materials consists of sulfur nanoparticles (65%), as well as nanoparticles of calcium compounds – vaterite (21%) and calcite (13%). Surface treatment of concrete with a sprayer leads to a decrease in water absorption from 5.4% to 3.1%, and in the case of treatment by immersion to a value of 1.5%, while the use of preliminary vacuuming before immersion of the samples allows achieving a water absorption parameter of 0.9%. It is shown that impregnation with preliminary vacuuming leads to water absorption values of less than 1%, which indicates the practical water impermeability of samples of full-scale products (concrete curbs and pipes). Discussion. It is noted that during surface treatment of aerated concrete with a sprayer, a chemically resistant superhydrophobic layer in the form of a nanocomposite is being formed, which penetrates to a depth of 3–3.5 cm, reliably protecting the material from water and chemical penetration. Surface treatment is effective in cases where objects (facades, above-ground structural elements, etc.) are exposed to water in the form of rain. Treatment of concrete products by immersion and immersion treatment with vacuuming can be carried out in harsh cases of constant water exposure (underground utilities, tunnels, manholes). Conclusions. The limitation of water penetration, and in some cases the absence of water in the pores of building materials impregnated with calcium polysulfide, indicate the preservation of substance, since water is a carrier of substances that destroy concrete and aerated concrete. Accordingly, there is no destructive effect from freezing of water in the pores of such materials as a result of the formation of a nano-sized coating of sulfur particles. Comparison of the results for aerated concrete shows that it acquires superhydrophobic properties, which indicates its excellent modification and expands the possibilities of its use. The data observed for concrete products indicate that after treatment with a calcium polysulfide-based solution, they can be used under conditions of long-term and constant exposure to water

Sodium allyl sulfonate (SAS) is a surfactant molecule that has occasional use as a monomer for the formation of functional polymers. A polymerization method is detailed herein, whereby it is demonstrated that the positioning of the individual functional groups can allow for the removal of protons adjacent to a sulfonate position before reaction with an electrophilic center to generate a polymeric material. In this case, sodium polysulfides are applied to promote the formation of a sulfur polymer using a mild synthesis that poses significant safety and energy benefits when compared to other methods of sulfur polymer generation, for example, inverse vulcanization. The polymer product that forms is demonstrated to retain all starting functionalities. Poly‐S‐SAS polymer also demonstrates impressive properties for application as a desiccant with a sorption maximum of 345 w/w % water, or as a flocculant material capable of removing up to 87% of different metals from low ppm solutions rapidly. [ABSTRACT FROM AUTHOR]

The utilization of lithium–sulfur battery is hindered by various challenges, including the "shuttle effect", limited sulfur utilization, and the sluggish conversion kinetics of lithium polysulfides (LiPSs). In the present work, a theoretical design for the viability of graphitic carbon nitride (g-C3N4) and phosphorus-doping graphitic carbon nitride substrates (P-g-C3N4) as promising host materials in a Li-S battery was conducted utilizing first-principles calculations. The PDOS shows that when the P atom is introduced, the 2p of the N atom is affected by the 2p orbital of the P atom, which increases the energy band of phosphorus-doping substrates. The energy bands of PC and Pi are 0.12 eV and 0.20 eV, respectively. When the lithium polysulfides are adsorbed on four substrates, the overall adsorption energy of PC is 48–77% higher than that of graphitic carbon nitride, in which the charge transfer of long-chain lithium polysulfides increase by more than 1.5-fold. It is found that there are powerful Li-N bonds between lithium polysulfides and P-g-C3N4 substrates. Compared with the graphitic carbon nitride monolayer, the anchoring effect of the LiPSs@P-g-C3N4 substrate is enhanced, which is beneficial for inhibiting the shuttle of high-order lithium polysulfides. Furthermore, the catalytic performance of the P-g-C3N4 substrate is assessed in terms of the S8 reduction pathway and the decomposition of Li2S; the decomposition energy barrier of the P-g-C3N4 substrate decrease by 10% to 18%. The calculated results show that P-g-C3N4 can promote the reduction of S8 molecules and Li-S bond cleavage within Li2S, thus improving the utilization of sulfur-active substances and the ability of rapid reaction kinetics. Therefore, the P-g-C3N4 substrates are a promising high-performance lithium-sulfur battery anchoring material. [ABSTRACT FROM AUTHOR]

The modification of polymer surfaces using laser light is important for many applications in the nano‐, bio‐ and chemical sciences. Such capabilities have supported advances in biomedical devices, electronics, information storage, microfluidics, and other applications. In most cases, these modifications require high power lasers that are expensive and require specialized equipment and facilities to minimize risk of hazardous radiation. Additionally, polymer systems that can be easily modified by lasers are often complex and costly to prepare. In this report, these challenges are addressed with the discovery of low‐cost sulfur copolymers that can be rapidly modified with lasers emitting low‐power infrared and visible light. The featured copolymers are made from elemental sulfur and either cyclopentadiene or dicyclopentadiene. Using a suite of lasers with discreet wavelengths (532, 638 and 786 nm) and powers, a variety of surface modifications could be made on the polymers such as controlled swelling or etching via ablation. The facile synthesis and laser modification of these polymer systems were exploited in applications such as direct laser lithography and erasable information storage. [ABSTRACT FROM AUTHOR]

Herein, we performed grafting of thiol groups to the surface of multi-walled carbon nanotubes. Then, using them (CNTS), zinc oxide (ZnO), ethylene dichloride, and sodium trisulfide (Na2S3), poly(ethylene trisulfide) (PETS) nanocomposites were synthesized via in situ polymerization. After that, the samples were cured at 170°C using a rheometer. The structural characteristics of CNTS were identified by Fourier transform infrared (FTIR), Raman spectroscopies, and X-ray diffraction (XRD). The PETS characteristics were investigated by FT-IR, Raman, X-ray diffraction (XRD), and proton nuclear magnetic resonance (1H NMR). Also, the samples were studied using scanning electron microscopy (SEM), Shore A, tensile tests, and differential scanning calorimetry (DSC). The results showed that CNTS has a significant effect on the curing time of the nanocomposites, so that the curing time decreases with increasing CNTS content. Moreover, the nanocomposites had improved mechanical properties, indicating that they are more resistant to deformation and fracture. In addition, after the curing process, the melting temperature (Tm) was not observed, and by increasing CNTS in composites, the glass transition temperature (Tg) occurs at higher temperatures. Furthermore, the hardness of the samples showed a slight increase with higher CNTS content. [ABSTRACT FROM AUTHOR]

The "shuttle effect" and sluggish conversion reaction kinetics of polysulfides seriously hinder the practical application of Li−S batteries. In this study, nano‐sized LaMnO3 (N‐LMO) with typical perovskite structure combined with highly‐conductive carbon black (SP) was introduced on the commercial separator to fabricate a functional surface modification. It is found that the polar N‐LMO with abundant active sites offers strong chemisorption towards the soluble polysulfides meanwhile accelerates their redox conversion, and the conductive SP contributes to extra spots to reactivate the trapped sulfur species. Consequently, the synergistic effect of adsorption‐catalysis‐conduction built by the cooperative N‐LMO/SP modification greatly enhances the sulfur redox kinetics as well as suppresses the polysulfide shuttling not at the expense of weakening Li‐ion transport, which endows the Li−S cell with a high initial discharge capacity of 1143.6 mAh g−1 at 0.2 C and a capacity decay rate of only 0.072 % per cycle at 1 C over 500 cycles. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li–S) batteries, with high energy density (2600 Wh/kg), are emerging as one of the most potential battery systems. However, the challenges posed by Li dendrite formation and polysulfide shuttling have impeded their commercialization. To address these issues, we develop a multifunctional separator featuring poly(methyl methacrylate) (PMMA) polymer coatings (PP@PMMA), synthesized via in-situ bond opening polymerization of oligomers catalyzed by Li + ions. This approach allows for the uniform application of the viscous PMMA oligomer onto the separator without requiring additional binders. Furthermore, the diffusion of liquid polysulfide is inhibited by the strong chemical bonding between the carbonyl group of PMMA gel polymer electrolyte (GPE) and lithium sulfide. Additionally, it also enhances the adsorption of solvents and promotes Li-ion conduction, thereby increasing the ion concentration of the interface layer and inhibiting the growth of dendrites. As a result, the Li||Li symmetric cell with PP@PMMA separator exhibits stable cycling for 1000 h, and the Li|Cu asymmetric cell achieves an average coulomb efficiency of 98.2% over 300 cycles. When applied to the 5000 mAh high specific energy Li–S pouch cell, the Li–S pouch cell with PP@PMMA can obtain a capacity retention rate of 97.6% after 100 cycles, while pristine Li–S battery is fully effective after only 35 cycles. Moreover, the optimized separator also mitigates self-discharge in Li–S batteries, and the storage capacity of 120 h is improved by 22%. The multifunctional separator can not only be applied in Li metal batteries but also promote the practical application of other Li-ion secondary batteries. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhengzhou University (Natural Science Edition) is the property of Journal of Zhengzhou University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The viologen component with redox activity in the ionic CMP serves as an electronic pump for donating electrons to and accepting electrons from sulfur species, which can facilitate the conversion of both solid lithium sulfide and soluble polysulfides. [Display omitted] The commercialization of lithium-sulfur (Li-S) batteries has been hindered by the shuttle effect and sluggish redox kinetics of lithium polysulfides (LiPSs). Herein, we reported a viologen-based ionic conjugated mesoporous polymer (TpV-Cl), which acts as the cathode host for modifying Li-S batteries. The viologen component serves as a reversible electron conveyer, leading to a comprehensive enhancement in the adsorption of polysulfides and improved conversion rate of polysulfides during the electrochemical process. As a result, the S@TpV-PS cathode exhibits outstanding cycling performance, achieving 300 cycles at 2.0 C (1 C = 1675 mA g−1) with low decay rate of 0.032% per cycle. Even at a high sulfur loading of 4.0 mg cm−2, S@TpV-PS shows excellent cycling stability with a Coulombic efficiency of up to 98%. These results highlight the significant potential of S@TpV-PS in developing high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

Despite the abundant reserves and high theoretical capacity of Na–S batteries, it is still limited by the sluggish reaction kinetics of polysulfides during ultrafast charging and discharging to provide stable and high sodium-ion storage performance. Herein, a catalytic strategy is proposed to change the direction of the Coulomb interaction of S–S bonds to achieve high rate reaction kinetics in polysulfides. In this strategy, a NaxVS2 structure is constructed in VS2/S nanocomposite electrodes to support S for superior performance (784 mA h/g at 0.1 A/g and 512 mA h/g at 10 A/g) during sodium storage process. The electrode can still exhibit stable cycling performance at a very high current density (5000 cycles at 20 A/g). The Na-inserted VS2 (NaxVS2) changes the charge distribution of S in polysulfide molecules, altering the Coulomb interaction between S atoms in polysulfide to form repulsion-induced breaking of S–S bond. This altering effect on the atomic Coulomb interaction is essential to promoting the conversion reaction of polysulfides. The above strategy of changing the Coulomb interaction between S atoms not only provides a reference for the design of nanostructures for electrochemical processes with multistep reactions but also inspires angles and ideas for realizing high-performance Na–S batteries. [ABSTRACT FROM AUTHOR]

Innate immunity plays an important role in host defense against microbial infections. It also participates in activation of acquired immunity through cytokine production and antigen presentation. Pattern recognition receptors such as Toll-like receptors and nucleotide oligomerization domain-like receptors sense invading pathogens and associated tissue injury, after which inflammatory mediators such as pro-inflammatory cytokines and nitric oxide are induced. Supersulfides are molecular species possessing catenated sulfur atoms such as persulfide and polysulfide moieties. They have recently been recognized as important regulators in cellular redox homeostasis by acting as potent antioxidants and nucleophiles. In addition, recent studies suggested that supersulfides are critically involved in the regulation of innate immune and inflammatory responses. In this review, we summarize current knowledge of the chemistry and biology of supersulfides, with particular attention to their roles in regulation of innate immune, and inflammatory responses. Studies with animal models of infection and inflammation demonstrated the potent anti-inflammatory functions of supersulfides such as blocking pro-inflammatory signaling cascades, reducing oxidative stresses, and inhibiting replication of microbial pathogens including severe acute respiratory syndrome coronavirus 2. Precise understanding of how supersulfides regulate innate immune responses is the necessary requirement for developing supersulfide-based diagnostic as well as therapeutic strategies against inflammatory disorders. [ABSTRACT FROM AUTHOR]

Significance: Routine exposure to xenobiotics is unavoidable during our lifetimes. Certain xenobiotics are hazardous to human health, and are metabolized in the body to render them less toxic. During this process, several detoxification enzymes cooperatively metabolize xenobiotics. Glutathione (GSH) conjugation plays an important role in the metabolism of electrophilic xenobiotics. Recent Advances: Recent advances in reactive sulfur and supersulfide (RSS) analyses showed that persulfides and polysulfides bound to low-molecular-weight thiols, such as GSH, and to protein thiols are abundant in both eukaryotes and prokaryotes. The highly nucleophilic nature of hydropersulfides and hydropolysulfides contributes to cell protection against oxidative stress and electrophilic stress. Critical Issues: In contrast to GSH conjugation to electrophiles that is aided by glutathione S-transferase (GST), persulfides and polysulfides can directly form conjugates with electrophiles without the catalytic actions of GST. The polysulfur bonds in the conjugates are further reduced by perthioanions and polythioanions derived from RSS to form sulfhydrated metabolites that are no longer electrophilic but rather nucleophilic, and differ from metabolites that are formed via GSH conjugation. Future Directions: In view of the abundance of RSS in cells and tissues, metabolism of xenobiotics that is mediated by RSS warrants additional investigations, such as studies of the impact of microbiota-derived RSS on xenobiotic metabolism. Metabolites formed from reactions between electrophiles and RSS may be potential biomarkers for monitoring exposure to electrophiles and for studying their metabolism by RSS. Antioxid. Redox Signal. 40, 679–690. [ABSTRACT FROM AUTHOR]

Background. The problem of mineral deficiency is solved by introducing the main types of fertilizers into the soil: nitrogen, potassium and phosphorus. But at present, it is firmly established that sulfur is another most demanded macronutrient - an important element of plant nutrition, which improves the absorption of nitrogen compounds by agricultural crops and ensures its high quality. The article presents the results of pre-sowing and foliar treatment with sulfur nanoparticles on the yield and grain quality of soft spring wheat at various stages of growth. Purpose. The aim of the study is to evaluate the effect of presowing and foliar treatment with sulfur nanoparticles on the yield and grain quality of soft spring wheat of the Ekada variety at various stages of growth. Materials and methods. As a source of sulfur nanoparticles, a preparation based on calcium polysulfide was used, which, diluted to a concentration of 2%, leads to obtaining sulfur hydrosol. The sulfur particle sizes were determined using a laser particle size analyzer and a probe microscope, and the X-ray phase analysis was carried out on a diffractometer. We used soft spring wheat "Ekada 70", the characteristics of which were determined using laboratory and field experiments, which were carried out according to a completely randomized block scheme with three repetitions. Results. It was found that the treatment of wheat with sulfur nanoparticles at all stages of growth led to an improvement in the main indicators of wheat, including a higher yield and an increase in the protein content in wheat grain. Conclusion. Laboratory and field tests have shown that the treatment of soft wheat with a calcium polysulfide preparation has a positive effect on all key characteristics, from germination and number of productive stems to yield and protein content. The drug can be recommended for use as an environmentally friendly product that stimulates plant growth and increases the yield and quality of wheat.

Lithium-sulfur (Li-S) batteries are a promising option for energy storage due to their theoretical high energy density and the use of abundant, low-cost sulfur cathodes. Nevertheless, several obstacles remain, including the dissolution of lithium polysulfides (LiPS) into the electrolyte and a restricted operational temperature range. This manuscript presents a promising approach to addressing these challenges. The manuscript describes a straightforward and scalable in situ thermal polymerization method for synthesizing a quasi-solid-state electrolyte (QSE) by gelling pentaerythritol tetraacrylate (PETEA), azobisisobutyronitrile (AIBN), and a dual salt lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium nitrate (LiNO3)-based liquid electrolyte. The resulting freestanding quasi-solid-state electrolyte (QSE) effectively inhibits the polysulfide shuttle effect across a wider temperature range of −25 °C to 45 °C. The electrolyte’s ability to prevent LiPS migration and cluster formation has been corroborated by scanning electron microscopy (SEM) and Raman spectroscopy analyses. The optimized QSE composition appears to act as a physical barrier, thereby significantly improving battery performance. Notably, the capacity retention has been demonstrated to reach 95% after 100 cycles at a 2C rate. Furthermore, the simple and scalable synthesis process paves the way for the potential commercialization of this technology.

Lithium–sulfur (Li–S) batteries are one of the most promising next-generation energy storage systems due to their ultrahigh theoretical specific capacity. However, the sluggish redox kinetics and shuttle effect of lithium polysulfide of sulfur cathodes remain obstacles to their development. Herein, we synthesize a thin laminar composite TpPa-SO3H/2-Methylol-15-crown-5 solid-state electrolyte (TpPa-SO3H/15-C-5-OH SSE) by encapsulating the crown ether into nanoscale pores (1.2 nm) of TpPa-SO3H covalent organic framework (COF) through low-pressure filtration. Importantly, the hydrogen-bonding interaction between TpPa-SO3H COF and 15-C-5-OH largely enhances the stable existence of 15-C-5-OH in pores of TpPa-SO3H COF. The 15-C-5-OH confined in pores of TpPa-SO3H COF can form a long-range ordered cavity channel for effective Li+ transport. This endows TpPa-SO3H/15-C-5-OH SSE with high ionic conductivity of 1.31 × 10–5 S cm–1 at 30 °C and satisfactory Li+ transference number (tLi+) of 0.75. In addition, the negative charge of the sulfonate group on the TpPa-SO3H COF can repel the polysulfide anions efficiently through an electrostatic repulsion interaction, thereby blocking the migration of polysulfide. As a result, the Li–S battery with TpPa-SO3H/15-C-5-OH SSE presents superior cycling stability, which preserves a capacity of 739.9 mA h g–1 with a retention of 82.9% after 400 cycles at 60 and 0.5C. [ABSTRACT FROM AUTHOR]

The presence of organic molecules containing sulfur-sulfur bonds was documented in the water columns and sediments of the natural aquatic systems as well as in fossil fuels. These compounds range from small molecules of volatile organic compounds to polysulfide cross-linked macromolecules in the sediments. While processes leading to formation of these compounds were intensively studied during the last decades, kinetics and mechanisms of reactions which lead to their decomposition are poorly understood. In this work, the kinetics and products of the reactions of dimethyl disulfide, dimethyl trisulfide, and cyclic polysulfide lenthionine (1,2,3,5,6-pentathiepane) with hydrogen sulfide at the environmental pH and temperature ranges were studied. It was shown that at pH ≥ 5, the reaction of bisulfide anion (HS–) rather than that of hydrogen sulfide controls the overall reaction rates. The activation energy and the order of the reaction with respect to bisulfide anion is dimethyl disulfide– < dimethyl trisulfide < lenthionine, while the order of the reaction with respect to organosulfur compounds is lenthionine < dimethyl trisulfide < dimethyl disulfide. The obtained results suggest that bisulfide anion is responsible for fast decomposition of organosulfur compounds in aphotic natural aquatic systems. This observation leads to the conclusion that sulfurization of sedimentary organic matter during the early diagenesis is not an unidirectional but a dynamic process, and concentrations of organic compounds with sulfur-sulfur bonds are controlled by the polysulfide to sulfide sulfur concentrations ratio in the sedimentary pore waters. In addition, the cyclic polysulfides were shown to be more stable than their linear analogs that results in preferential preservation of these compounds during the maturation process. [ABSTRACT FROM AUTHOR]

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The reaction rate bottleneck during interconversion between insulating S8 (S) and Li2S fundamentally leads to incomplete conversion and restricted lifespan of Li−S battery, especially under high S loading and lean electrolyte conditions. Herein, we demonstrate a new catalytic chemistry: soluble semiquinone, 2‐tertbutyl‐semianthraquinone lithium (Li+TBAQ⋅−), as both e‐/Li+ donor and acceptor for simultaneous S reduction and Li2S oxidation. The efficient activation of S and Li2S by Li+TBAQ⋅− in the initial discharging/charging state maximizes the amount of soluble lithium polysulfide, thereby substantially improve the rate of solid–liquid‐solid reaction by promoting long‐range electron transfer. With in situ Raman spectra and theoretical calculations, we reveal that the activation of S/Li2S is the rate‐limiting step for effective S utilization under high S loading and low E/S ratio. Beyond that, the S activation ratio is firstly proposed as an accurate indicator to quantitatively evaluate the reaction rate. As a result, the Li−S batteries with Li+TBAQ⋅− deliver superior cycling performance and over 5 times higher S utilization ratio at high S loading of 7.0 mg cm−2 and a current rate of 1 C compared to those without Li+TBAQ⋅−. We hope this study contributes to the fundamental understanding of S redox chemical and inspires the design of efficient catalysis for advanced Li−S batteries. [ABSTRACT FROM AUTHOR]

The strategy of the Li-S cell with a dual-layer sulfur cathode (integrated thin layer of In 2 S 3 /Bi 2 S 3 @rGO between two thick-layer of sulfur) coupled with a coated layer on the separator could stop the shuttle effect happening on the bottom layer of sulfur and adsorb the polysulfide from the face side of the upper layer of sulfur. [Display omitted] The specific energies and energy densities of lithium–sulfur (Li-S) batteries are influenced by various cell parameters, including the sulfur loading, the sulfur weight percentage in the cathode, and the electrolyte/sulfur ratio. An In 2 S 3 /Bi 2 S 3 @rGO heterostructure was obtained by growing indium sulfide nanoparticles on the surface of bismuth sulfide nanoflowers in a graphene oxide (GO) solution via a one-step solvothermal approach. This structure was introduced as a modified separator/dual-layer sulfur cathode for Li-S batteries. The Bi 2 S 3 /In 2 S 3 heterointerfaces act as active sites to speed up interfacial electron transfer, along with the entrapment, diffusion, and transformation of lithium polysulfides. A Li-S cell containing a dual-layer sulfur cathode (thin layer of In 2 S 3 /Bi 2 S 3 @rGO sandwiched between two thick layers of sulfur) and coupled with an In 2 S 3 /Bi 2 S 3 @rGO-coated separator suppressed the polysulfide shuttle effect. The cell based on the dual-layer sulfur cathode technology and operated at a current rate of 0.3C achieved a high capacity (7.1 mAh cm−2) after the 200th cycle, giving an electrolyte/sulfur ratio (10 µL mg−1) under a high sulfur loading (11.53 mg cm−2). These results demonstrate the unique nature of the dual-layer sulfur cathode technique, which can yield high energy density Li-S batteries with high sulfur loadings and low electrolyte/sulfur ratios. [ABSTRACT FROM AUTHOR]

This study investigated tribofilm layers formed under boundary lubrication using a polysulfide additive on S45C and SUS304 steel surfaces. In the tribotests, the friction coefficient of the SUS304 disc fluctuated and increased more gradually in comparison to that of the S45C disc. The tribofilm on the S45C disc comprised the outermost and inner layers of FeS2 (pyrite) and FeS (troilite), respectively. Notably, all the tribofilm layers on the SUS304 disc surface contained pyrite. The tribofilm on the SUS304 disc was weakly crystalline in the outermost layer and thinner than that on the S45C disc. The poor formation of the tribofilm on the SUS304 disc was potentially caused by the unstable friction coefficient and scuffing. [ABSTRACT FROM AUTHOR]

The global rapid transition from fossil fuels to renewable energy resources necessitates the implementation of long‐duration energy storage technologies owing to the intermittent nature of renewable energy sources. Therefore, the deployment of grid‐scale energy storage systems is inevitable. Sulfur‐based batteries can be exploited as excellent energy storage devices owing to their intrinsic safety, low cost of raw materials, low risk of environmental hazards, and highest theoretical capacities (gravimetric: 2600 Wh/kg and volumetric: 2800 Wh/L). However, sulfur‐based batteries exhibit certain scientific limitations, such as polysulfide crossover, which causes rapid capacity decay and low Coulombic efficiency, thereby hindering their implementation at a commercial scale. In this review article, we focus on the latest research developments between 2012–2023 to improve the separators/membranes and overcome the shuttle effect associated with them. Various categories of ion exchange membranes (IEMs) used in redox batteries, particularly polysulfide redox flow batteries and lithium‐sulfur batteries, are discussed in detail. Furthermore, advances in IEM constituents are summarized to gain insights into different fundamental strategies for attaining targeted characteristics, and a critical analysis is proposed to highlight their efficiency in mitigating sulfur cross‐shuttling issues. Finally, future prospects and recommendations are suggested for future research toward the fabrication of more effective membranes with desired properties. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery has become one of the most attractive power battery systems in the future because of their high specific energy, high energy density, good safety, green environmental protection, low cost, and so on. However, due to the "shuttle effect" caused by its polysulfide discharge product, the lithium-sulfur battery's cycle performance is poor, limiting the rapid development of lithium-sulfur batteries. In this paper, oxygen-doped hazel shell-graded porous derivative carbon with a high specific surface area was prepared by a simple template-free method and used as the functional layer of the diaphragm. Oxygen self-doping is beneficial to forming oxygen-containing functional groups on the surface, which can realize the chemical adsorption of polysulfides. The multi-stage pore structure enhances the physical confinement effect of carbon materials on polysulfides. In addition, it is found that the initial capacity of the modified diaphragm can reach 1318.8 mAh g-1 at 0.2C current density. And the initial capacity can still reach 1035.6 mAh g-1 even at 1 C current density, after 500 cycles, the capacity retention rate is 60.9%, which has good rate performance and cycle stability. [Display omitted] • A novel method of preparation. • Special biochar materials and morphologies. • Excellent battery performance. [ABSTRACT FROM AUTHOR]

Significance: Persulfides/polysulfides are sulfur-catenated molecular species (i.e., R-Sn-R′, n > 2; R-Sn-H, n > 1, with R = cysteine, glutathione, and proteins), such as cysteine persulfide (CysSSH). These species are abundantly formed as endogenous metabolites in mammalian and human cells and tissues. However, the persulfide synthesis mechanism has yet to be thoroughly discussed. Recent Advances: We used β-(4-hydroxyphenyl)ethyl iodoacetamide and mass spectrometry to develop sulfur metabolomics, a highly precise, quantitative analytical method for sulfur metabolites. Critical Issues: With this method, we detected appreciable amounts of different persulfide species in biological specimens from various organisms, from the domains Bacteria, Archaea, and Eukarya. By using our rigorously quantitative approach, we identified cysteinyl-tRNA synthetase (CARS) as a novel persulfide synthase, and we found that the CysSSH synthase activity of CARS is highly conserved from the domains Bacteria to Eukarya. Because persulfide synthesis is found not only with CARS but also with other sulfotransferase enzymes in many organisms, persulfides/polysulfides are expected to contribute as fundamental elements to substantially diverse biological phenomena. In fact, persulfide generation in higher organisms—that is, plants and animals—demonstrated various physiological functions that are mediated by redox signaling, such as regulation of energy metabolism, infection, inflammation, and cell death, including ferroptosis. Future Directions: Investigating CARS-dependent persulfide production may clarify various pathways of redox signaling in physiological and pathophysiological conditions and may thereby promote the development of preventive and therapeutic measures for oxidative stress as well as different inflammatory, metabolic, and neurodegenerative diseases. Antioxid. Redox Signal. 39, 983–999. [ABSTRACT FROM AUTHOR]

Transition metal sulphides based on conversion reaction mechanism have attracted much attention as anode materials for sodium‐ion batteries owing to their theoretical specific capacity and potential long lifespan. The unsatisfactory Coulombic efficiency, however, inhabits the cycling lifespan due to the intermediate polysulfide formation (Na2Sx; 4≤x≤6) and chain reactions. To enhance the polysulfide polysulfide adsorption capability and capacity, a hybrid with synergistic sodium storage and polysulfide adsorption capability was designed, in which massive CoS2 nanoparticles (CoS2 NP) were utilized as electrons supplier to enhance the adsorption energy of three‐dimensional nitrogen‐doped carbon (3D‐NC) framework towards sodium polysulfide. Combining the experimental and computational results, the encapsulated CoS2 can dramatically optimize the local electronic structure and function as a powerful electron reservoir to increase the effective adsorption to Na2Sx (4≤x≤6). Meanwhile, the electron transferring between CoS2 NP and 3D‐NC can facilitate the conversion of Na2S to Na2Sx. An ultra‐high initial Coulombic efficiency of 98.05 % and 98.38 % can be achieved at current densities of 0.06 A g−1 and 0.4 A g−1, respectively. Beneficial from the high reversible capability, a superior cycling lifespan is obtained up to 800 long cycles at current densities of 0.6 A g−1. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries are considered as the most promising energy storage devices owing to their high theoretical energy density and theoretical specific capacity. But some problems hinder their practical application, including low electronic conductivity and polysulfide migration during discharge–charge process. In this work, C/MoS2 heterostructure composites constructed by in situ growth of MoS2 on porous carbon are developed as the sulfur host for lithium-sulfur batteries. The introduction of porous carbon could improve the electronic conductivity of the cathode, as well as the C/MoS2 heterostructure could accelerate the redox kinetics and inhibit the shuttle effect via the adsorption with polysulfide. All of these advantages could improve the electrochemical performance of the lithium-sulfur batteries. This work demonstrates that the employment of hybrid composites as sulfur host is a promising method to improve the electrochemical performance of lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

The utilization of lithium–sulfur battery is hindered by various challenges, including the “shuttle effect”, limited sulfur utilization, and the sluggish conversion kinetics of lithium polysulfides (LiPSs). In the present work, a theoretical design for the viability of graphitic carbon nitride (g-C3N4) and phosphorus-doping graphitic carbon nitride substrates (P-g-C3N4) as promising host materials in a Li-S battery was conducted utilizing first-principles calculations. The PDOS shows that when the P atom is introduced, the 2p of the N atom is affected by the 2p orbital of the P atom, which increases the energy band of phosphorus-doping substrates. The energy bands of PC and Pi are 0.12 eV and 0.20 eV, respectively. When the lithium polysulfides are adsorbed on four substrates, the overall adsorption energy of PC is 48–77% higher than that of graphitic carbon nitride, in which the charge transfer of long-chain lithium polysulfides increase by more than 1.5-fold. It is found that there are powerful Li-N bonds between lithium polysulfides and P-g-C3N4 substrates. Compared with the graphitic carbon nitride monolayer, the anchoring effect of the LiPSs@P-g-C3N4 substrate is enhanced, which is beneficial for inhibiting the shuttle of high-order lithium polysulfides. Furthermore, the catalytic performance of the P-g-C3N4 substrate is assessed in terms of the S8 reduction pathway and the decomposition of Li2S; the decomposition energy barrier of the P-g-C3N4 substrate decrease by 10% to 18%. The calculated results show that P-g-C3N4 can promote the reduction of S8 molecules and Li-S bond cleavage within Li2S, thus improving the utilization of sulfur-active substances and the ability of rapid reaction kinetics. Therefore, the P-g-C3N4 substrates are a promising high-performance lithium-sulfur battery anchoring material.

Hydropersulfide and hydropolysulfide metabolites are increasingly important reactive sulfur species (RSS) regulating numerous cellular redox dependent functions. Intracellular production of these species is known to occur through RSS interactions or through translational mechanisms involving cysteinyl t-RNA synthetases. However, regulation of these species under cell stress conditions, such as hypoxia, that are known to modulate RSS remain poorly understood. Here we define an important mechanism of increased persulfide and polysulfide production involving cystathionine gamma lyase (CSE) phosphorylation at serine 346 and threonine 355 in a substrate specific manner, under acute hypoxic conditions. Hypoxic phosphorylation of CSE occurs in an AMP kinase dependent manner increasing enzyme activity involving unique inter- and intramolecular interactions within the tetramer. Importantly, both cellular hypoxia and tissue ischemia result in AMP Kinase dependent CSE phosphorylation that regulates blood flow in ischemic tissues. Our findings reveal hypoxia molecular signaling pathways regulating CSE dependent persulfide and polysulfide production impacting tissue and cellular response to stress.

Higher consumption of broccoli (Brassica oleracea var. italica) is associated with a reduced risk of cardiometabolic diseases, neurological disorders, diabetes, and cancer. Broccoli is rich in various phytochemicals, including glucosinolates, and isothiocyanates. Moreover, it has recently reported the endogenous production of polysulfides, such as cysteine hydropersulfide (CysS2H) and glutathione hydropersulfide (GS2H), in mammals including humans, and that these bioactive substances function as potent antioxidants and important regulators of redox signaling in vivo. However, few studies have focused on the endogenous polysulfide content of broccoli and the impact of germination on the polysulfide content and composition in broccoli. In this study, we investigated the alternations in polysulfide biosynthesis in broccoli during germination by performing untargeted polysulfide omics analysis and quantitative targeted polysulfide metabolomics through liquid chromatography–electrospray ionization–tandem mass spectrometry. We also performed 2,2-diphenyl-1-picrylhydrazyl radical–scavenging assay to determine the antioxidant properties of the polysulfides. The results revealed that the total polysulfide content of broccoli sprouts significantly increased during germination and growth; CysS2H and cysteine hydrotrisulfide were the predominant organic polysulfide metabolites. Furthermore, we determined that novel sulforaphane (SFN) derivatives conjugated with CysS2H and GS2H were endogenously produced in the broccoli sprouts, and the novel SFN conjugated with CysS2H exhibited a greater radical scavenging capacity than SFN and cysteine. These results suggest that the abundance of polysulfides in broccoli sprouts contribute to their health-promoting properties. Our findings have important biological implications for the development of novel pharmacological targets for the health-promoting effects of broccoli sprouts in humans.

Developing polyoxometalate‐cyclodextrin cluster‐organic supramolecular framework (POM‐CD‐COSF) still remains challenging due to an extremely difficult task in rationally interconnecting two dissimilar building blocks. Here we report an unprecedented POM‐CD‐COSF crystalline structure produced through the self‐assembly process of a Krebs‐type POM, [Zn2(WO2)2(SbW9O33)2]10−, and two β‐CD units. The as‐prepared POM‐CD‐COSF‐based battery separator can be applied as a lightweight barrier (approximately 0.3 mg cm−2) to mitigate the polysulfide shuttle effect in lithium‐sulfur batteries. The designed Li−S batteries equipped with the POM‐CD‐COSF modified separator exhibit remarkable electrochemical performance, attributed to fast Li+ diffusion through the supramolecular channel of β‐CD, efficient polysulfide‐capture ability by the dynamic host–guest interaction of β‐CD, and improved sulfur redox kinetics by the bidirectional catalysis of POM cluster. This research provides a broad perspective for the development of multifunctional supramolecular POM frameworks and their applications in Li−S batteries. [ABSTRACT FROM AUTHOR]

A detailed process mineralogical study was conducted on a polysulfide gold - copper ore. Based on the study, flotation experiments were carried out, and the loss of gold and copper was investigated. The results showed that gold copper and sulfur are valuable elements, with gold grade of 0. 60 g/ t, copper grade of 0. 17 %, and sulfur content of 16. 13 %. The main copper mineral is chalcopyrite, predominantly in fine grains with high degree of monomer dissociation. The main gold mineral is native gold, predominantly in fine grains, with sulfide-encased gold accounting for 49. 05 %. The joint process of regrinding - gravity tailings bulk flotation - copper-sulfur separation from the bulk concentrate (three-stage cleaning) achieved total recovery rates of 91. 70 % for copper, 50. 21 % for gold, and 90. 93 % for sulfur. The recovery effect of the target minerals was good, and the loss of gold and copper in the tailings was mainly due to inclusion in gangue minerals, consistent with the results of the process mineralogical study. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery is a kind of energy storage system with high specific capacity, low production cost and environmental friendliness. It has great development potential and application prospect in portable electronic device energy storage. However, lithium-sulfur batteries still face the problems of low Coulomb efficiency and short lifespan in practical applications. This is mainly attributed to polysulfide shuttle effect, low electrical conductivity of S8 and Li2S and uncontrolled lithium dendrite growth. The inhibition of lithium dendrite growth and the inhibition of the reaction between soluble polysulfide and lithium can not only enhance the safety and electrochemical performance of lithium sulfur batteries, but also play an important role in high-capacity lithium sulfur batteries. In this paper, the development of lithium-sulfur battery is reviewed, and the progress of high-sulfur loaded lithium battery is introduced emphatically. By analyzing the mechanism, we can understand the operation mechanism of lithium sulfur battery and develop improvement methods, including the use of graded porous carbon for cathode and element doping to increase the sulfur loading rate of active substance and reduce the shuttle effect of polysulfide. The development of liquid and solid electrolyte systems and strategies to enhance anode stability are also introduced. In addition, we believe that in-depth understanding of the mechanism of lithium-sulfur batteries can strengthen the cognition of lithium-sulfur batteries and guide the future development of high-sulfur loaded lithium-sulfur batteries. At the same time, improving synergies between components can further advance lithium-sulfur battery technology from button batteries and flexible pack batteries to subsequent commercial scale applications.

High-level ab initio and density functional theory were applied to investigate property and reactivity of polyselenides and polysulfides. With CH3XnH (X = S or Se) we found that the deprotonation energy (and pKa) of CH3SenH, ionization potential (IP) of , and CH3Sen−H bond dissociation energy (BDE) are lower than those of their sulfur counterparts. For n = 2, IPs and X−H BDEs are exceptionally small. The relative nucleophilicity of C H 3 X n − vary with substrates. However, CH3SenH are more nucleophilic than CH3SnH due to their due to their lower deprotonation energy. The nucleophilicity of selenolates versus thiolates are related to the chemical nature. Selenium is more electrophilic than sulfur. [ABSTRACT FROM AUTHOR]

Functionalized carbon based 2D materials are promising candidates for low cost and environment friendly electrocatalyst for hydrogen evolution reaction (HER) and supercapacitor applications. To overcome the limitations posed by the noble metals and transition metal based composites, we have successfully synthesized metal free polysulfide functionalized reduced graphene oxide (GPS) in a simple chemical route. Structure and morphology of the material are characterized via XRD, FTIR, Raman, TEM, XPS measurements. The material behaves as an efficient HER electrocatalyst in acidic medium as well as energy storage device. It shows an onset potential of 97 mV and overpotential of 254 mV to reach a high current density of 10 mA/cm2. DFT calculations are carried out to understand the structural stability and identification of active sites of the material. Boosting catalytic activity via increasing the number of active sites is an elegant approach. In this material we have used the S atoms of polysulfide polymer to facilitate hydrogen adsorption and desorption, thus improving the hydrogen evolution ability. The supecapacitor attains the high specific capacitance 347 F/g at the current density of 1 A/g. The origin of such performances is due to synergistic effect of both the graphene network and the polysulfide functionalizations. [Display omitted] • The reduced graphene oxide – polysulfide (GPS) composite has been fabricated via simple condensation strategy. • The electron cloud delocalisation between sulfur atoms create fast electron transfer pathway for HER & supercapacitor. • The polysulfide functionalization creates active sites and effectively improves the catalytic and charge storage properties. • An inexpensive carbon based metal-free catalyst and energy storage device is introduced. [ABSTRACT FROM AUTHOR]

To develop a fluorescent probe for hydrogen polysulfides (H2Sn, n≥2) based on protection‐deprotection chemistry, we protected fluorescein with nitrobenzenesulfonyl groups bearing various substituents with different electrophilic reactivities, and evaluated their responsiveness toward H2Sn. 3′‐O‐(2‐Nitrobenzenesulfonyl)fluorescein (1 c) provided the best sensitivity toward H2Sn and selectivity over hydrogen sulfide and glutathione. Further evaluation demonstrated that 1 c was an excellent probe, comparable with PSP‐3, one of the best H2Sn probes developed to date. The attractive features of 1 c were capitalized on by synthesizing the acetylated derivative from 1 c, which was shown to be cell‐permeable and applicable to the fluorescent imaging of H2Sn in HeLa cells. [ABSTRACT FROM AUTHOR]

Background. It is important to obtain sulfur concrete by modifying technical sulfur obtained as a result of oil and gas processing in the territory of Uzbekistan. Purpose. Production of sulfur concrete based on synthesized polymer sulfur and analysis of its physical and mechanical properties. Methodology. IR spectroscopy was used to determine the functional groups in polymer sulfur. The change in concrete thickness and mechanical strength at a temperature of 80 °C was determined based on ПНСТ105-2016. Originality. Optimum conditions for obtaining polymer sulfur from technical sulfur were determined and its structure was explained by spectroscopic methods. The optimal amount of polymer sulfur required for the preparation of sulfur concrete mixture has been scientifically proven. Findings. Samples of sulfur concrete were prepared based on synthesized polymer sulfur. The change in the mechanical strength of sulfur concrete samples depending on the storage period has been scientifically analyzed. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries are regarded as one of the most promising energy storage systems due to their high specific capacity and energy density. However, the severe shuttle effect of long-chain polysulfide leads to low active sulfur utilization, resulting in rapid capacity fading and poor cycle stability. And this hinders the practical application of lithium-sulfur batteries. In this work, MoS2 nanosheets@hollow carbon spheres (MSNSs@HCSs) composites are prepared and employed as the separator coating materials of lithium-sulfur batteries. The MSNSs@HCSs could adsorb the polysulfide and accelerate the conversion of long-chain polysulfide to short-chain ones, thereby inhibiting the polysulfide shuttle effect. As a result, lithium-sulfur batteries with MSNSs@HCSs coated separators could deliver a high initial specific capacity of 1182 mAh/g at 0.2 C. Moreover, when the rate increased to 2 C, the capacity could reach 806 mAh/g after 300 cycles at 2 C. [ABSTRACT FROM AUTHOR]

The potential application of two electrolyte additives, NiCl2‐DME and NiF2‐DME, in lithium–sulfur batteries is investigated by density functional theory calculations. The results show that both electrolyte additives can effectively adsorb soluble lithium polysulfide (LiPSs) in the electrolyte. With the progress of the charging–discharge reaction, NiCl2 and NiF2 separate from Li2Sn when it is converted to S8 and recombine with 1,2‐dimethoxy‐ethane (DME) to achieve the purpose of cyclic adsorption of polysulfide in the electrolyte. At the same time, NiF2 and NiCl2 also have a catalytic effect in the cycling process. When adsorbed with Li2Sn, the bond length of the Li–S bond in Li2Sn is elongated, which causes the reduction of the Li2Sn activation energy, making it easier to be oxidized, and accelerating the conversion speed of Li2Sn and reducing Li2S, Li2S2 deposition on the surface of the electrode. Therefore, NiCl2‐DME and NiF2‐DME are ideal dual‐function electrolyte additives. [ABSTRACT FROM AUTHOR]

The development of a low-cost, and highly effective platinum (Pt)-free counter electrode (CE) that is highly stable towards polysulfide electrolyte presents a substantial challenge. Trigonal Molybdenum disulfide (1T-MoS _2 ) has shown good chemical stability toward polysulfide electrolytes. In this study, 1T-MoS _2 was prepared by co-doping with nickel (Ni) and selenium (Se) into MoS _2 through hydrothermal method and utilizing its reduction activity toward polysulfide electrolyte. According to electrochemical impedance spectroscopy (EIS) analysis, Ni-Se-MoS _2 has a low charge transfer resistance and electron recombination lifetime. In addition, cyclic voltmeter (CV) analysis reveals a high absolute area indicating a high level of electrocatalytic activity for polysulfide reduction at the electrolyte/counter electrode (CE) interface. The XRD analysis shows that the phase shifting of 2H MoS _2 to 1 T MoS _2 and the intensity of the co-doped sample is lower than that of others. SEM analysis reveals a microsphere-flower-like morphology that increases specific surface area.