Search Results (387)

Room-temperature sodium–sulfur (RT Na-S) batteries hold great potential in the field of large-scale energy storage due to their high theoretical energy density and low cost of raw materials. However, the inherent low conductivity, notorious shuttling, and sluggish kinetics of cathode materials cause the loss of active substances and capacity delay, hindering the practical application of RT Na-S batteries. Owing to their low cost, variable oxidation states, and unsaturated d orbitals, transition metal (TM)-based catalysts have been extensively studied in circumventing the above shortcomings. Herein, the review first elaborates on the reaction mechanisms and current challenges of RT Na-S batteries. Subsequently, the role and function mechanism of TM-based catalysts (including single/dual atoms, nanoparticles, compounds, and heterostructures) in RT Na-S batteries are described. Specifically, based on the theories of electronic transfer and atomic orbital hybridization, the interaction mechanism between TM-based catalysts and polysulfides, as well as the catalytic performance, are systematically discussed and summarized. Finally, a discussion on the challenges and future research perspectives associated with TM-based catalysts for RT Na-S batteries is provided. Full article

Metal–organic frameworks (MOFs) and their derivatives have emerged as promising candidates for separator engineering in lithium–sulfur batteries (LSBs). This is attributed to their structural tunability, high porosity, and chemical versatility. Despite their potential, challenges such as lithium polysulfide (LiPS) shuttling, sluggish redox kinetics, and poor interfacial stability still hinder the practical deployment of LSBs. This review examines recent advances in MOF- and MOF derivative-based materials for separator modification, focusing on design strategies, functional mechanisms, and electrochemical performance. Pristine MOFs are classified into the following three key structural tuning strategies: control of the pore microenvironment, engineering of metal sites, and enhancement of electrical conductivity. Meanwhile, MOF derivatives are examined using compositional categories to highlight their distinct chemical characteristics and catalytic functionalities for LiPS regulation. Key findings demonstrate that these materials can effectively suppress polysulfide migration, accelerate LiPS redox reactions, and improve lithium-ion transport across the separator. The review also identifies remaining challenges and suggests future perspectives for bridging material-level innovations with system-level applications. Overall, MOF-based separator materials represent a versatile and impactful approach for advancing the electrochemical performance and stability of next-generation LSBs. Full article

Lithium–iron disulfide (Li-FeS₂) batteries are plagued by the polysulfide shuttle effect and cathode structural degradation, which significantly hinder their practical application. This study proposes a dual-strategy design that combines a polyacrylonitrile–carbon nanotube (PAN-CNT) composite cathode and a polyvinylidene fluoride (PVDF)-conductive carbon-coated separator to synergistically address these bottlenecks. The PAN-CNT binder establishes chemical anchoring between polyacrylonitrile and FeS₂, enhancing electronic conductivity and mitigating volume expansion. Specifically, the binder boosts the initial discharge capacity by 35% while alleviating the stress-induced pulverization associated with volume changes. Meanwhile, the PVDF-conductive carbon-coated separator enables effective polysulfide trapping via dipole–dipole interactions between PVDF’s polar C-F groups and Li₂S_x species while maintaining unobstructed ion transport with an ionic conductivity of 1.23 × 10⁻³ S cm⁻¹, achieving a Coulombic efficiency of 99.2%. The electrochemical results demonstrate that the dual-modified battery delivers a high initial discharge capacity of 650 mAh g⁻¹ at 0.5 C, with a capacity retention rate of 61.5% after 120 cycles, significantly outperforming the control group’s 47.5% retention rate. Scanning electron microscopy and electrochemical impedance spectroscopy confirm that this synergistic design suppresses polysulfide migration and enhances interfacial stability, reducing the charge transfer resistance from 26 Ω to 11 Ω. By integrating polymer-based functional materials, this work presents a scalable and cost-effective approach for developing high-energy-density Li-FeS₂ batteries, providing a practical pathway to overcome key challenges in their commercialization. Full article

Ischemia-reperfusion (I/R) injury refers to the exacerbation of tissue or organ damage upon the restoration of blood flow after an ischemic event. Despite its widespread clinical occurrence, therapeutic interventions for I/R injury remain limited in efficacy, presenting a significant challenge in modern medicine. Garlic, traditionally consumed as a food, has gained considerable attention for its medicinal properties. Numerous animal studies have shown that garlic-derived organic polysulfides significantly improve nerve function scores post-I/R, reduce infarct size, mitigate inflammatory responses, and inhibit cellular apoptosis. Thus, understanding the role of garlic-derived organic polysulfides in I/R injury may unveil novel therapeutic targets. This review explores the protective effects and mechanisms of garlic-derived organic polysulfides on I/R injury in various organs, including the brain, spinal cord, myocardium, lungs, liver, kidneys, and testes, highlighting their potential in advancing treatment strategies for affected patients. Full article

Commercialization of lithium-sulfur (Li-S) batteries is critically hampered by the severe lithium polysulfide shuttle effect. Hence, designing multifunctional materials that synergistically provide physical confinement of polysulfides, chemical entrapment, and catalytic promotion is a viable route for improving Li-S battery performance. Herein, graphitic carbon nitride (g-C₃N₄) with abundant nitrogen atoms was used as the chemical adsorption material to realize a “physical-chemical” dual confinement for polysulfides. Furthermore, the integration of CNTs with g-C₃N₄ is intended to substantially enhance the conductivity of the cathode material. Consequently, the synthesized g-C₃N₄/CNT composite, which functions as an effective polysulfide immobilizer, significantly improved the cycling stability and discharge capacity of Li-S batteries. This enhancement can be attributed to its potent adsorption and catalytic activities. Li-S cells utilizing g-C₃N₄/CNT cathodes exhibit exceptional discharge capacity and notable rate capability. Specifically, after 100 cycles at 0.2 C, the discharge capacity was 701 mAh g⁻¹. Furthermore, even at a high rate of 2 C, a substantial capacity of 457 mAh g⁻¹ was retained. Full article

Polymers have long been utilized in various industries due to their unique properties. Among the family of polymers, polysulfides are popular due to their strong adhesion and high resistance to fuels and solvents, and have been utilized in specific applications. In this study, polysulfide nanocomposites were prepared using methylene dichloride (MD), sodium tetrasulfide (Na₂S₄), and reduced graphene oxide (rGO) and then cured using a rheometer. Polymethylene tetrasulfide (PMTS) and nanocomposites were evaluated by Fourier transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Also, the cured samples were evaluated using FTIR, XRD, SEM, thermogravimetric analysis (TGA), and tensile test. The results showed that PMTS has a completely amorphous structure. XRD and SEM results showed that with the addition of rGO, free sulfur accumulates in the matrix, which participates in the reaction during the curing process. The cured polymethylene tetrasulfide (CPMTS) and the cured nanocomposites have a completely amorphous structure. Also, the presence of rGO improved the final properties of the product. Full article

Severe polysulfide shuttling and sluggish redox kinetics critically hinder lithium–sulfur (Li-S) battery commercialization. In this study, a multifunctional diatomite (DE)/TiO₂/MoS₂/N-doped carbon nanofiber (NCNF) composite separator was fabricated via hydrothermal synthesis, electrospinning, and carbonization. DE provides dual polysulfide suppression, encompassing microporous confinement and electrostatic repulsion. By integrating synergistic catalytic effects from TiO₂ and MoS₂ nanoparticles, which accelerate polysulfide conversion, and conductive NCNF networks, which facilitate rapid charge transfer, this hierarchical design achieves exceptional electrochemical performance: a 1245.6 mAh g⁻¹ initial capacity at 0.5 C and 65.94% retention after 200 cycles. This work presents a rational multi-component engineering strategy to suppress shuttle effects in high-energy-density Li-S batteries. Full article

Background: 1,2,3,4,5-pentathiepines (PTEs) are compounds originally identified in marine ascidians and are currently under investigation for their promising pharmacological properties, particularly as potential antineoplastic agents. Objectives: In this study, we investigated the antineoplastic properties of a series of ten indolizine-based PTEs, comprising eight previously reported compounds and two newly synthesized derivatives. Methods: These compounds were evaluated against a panel of human cancer cell lines of diverse tissue origins, as well as, for the first time, on non-cancerous CR9 fibroblasts to assess their cytotoxic selectivity. In addition, their effects were tested on 3D spheroid models, providing preliminary insights into their potential in vivo efficacy. Initial screening focused on cell viability, followed by a more detailed characterization of the most active compounds in terms of their ability to induce apoptosis, necrosis, cell cycle arrest, and reactive oxygen species (ROS) generation. The anti-migratory activity of PTEs and a newly adapted assay to confirm sulfur species release in the cells were also performed for the first time. Results and Conclusions: Our findings reveal that four PTEs bearing hydrophilic, hydrogen-bonding functional groups, particularly the two inspired by natural analogs, exhibited the most potent anticancer activity. Full article

Films of functionalised multiwalled carbon nanotubes (MWCNTs) were fabricated as interlayers (interfacial layers between the cathode and separator) in a lithium–sulfur battery (LSB). Phenylsulfonate functionalisation of commercial MWCNTs was achieved via diazotisation to attach lithium phenylsulfonate groups and was characterised by IR and XPS spectroscopies. SEM-EDX showed sulfur and oxygen colocations due to the sulfonate groups on the interlayer surface. However, CHNS elemental microstudies showed a low degree of functionalisation. Without an interlayer, the LSB produced stable cycling at a capacity of 600 mA h g⁻¹_sulfur at 0.05 C for 40 cycles. Using an unfunctionalised interlayer as a control gave a capacity of 1400 mA h g⁻¹_sulfur for the first cycle but rapidly decayed to the same 600 mA h g⁻¹_sulfur at the 40th cycle at 0.05 C, suggesting a high degree of polysulfide shuttling. Adding a lithium phenylsulfonated interlayer gave an initial capacity increase to 1100 mA h g⁻¹_sulfur that lowered to 800 mA h g⁻¹_sulfur at 0.05 C by the 40th cycle, showing an increase in charge storage (33%) relative to the other cells. This performance increase has been attributed to lessened polysulfide shuttling due to repulsion by the phenylsulfonate groups, increased conductivity at the separator-cathode interface and an increase in surface area. Full article

Sulfur-containing polymers are unique sustainable materials with promise for the development of various adsorbents for environmental remediation. However, they have not been explored for CO₂ capture despite reports on its ability to decontaminate various aqueous pollutants. This study reports on the single-step synthesis of a diamine-functionalized sulfur-containing copolymer by the thermally induced radical copolymerization of N2,N2-Diallylmelamine (NDAM), a difunctional monomer, with sulfur and explores its use for CO₂ capture. The influence of reaction parameters such as the weight ratios of sulfur to NDAM, reaction temperature, time, and the addition of a porogen on the properties of aminated copolymer was investigated. The resulting copolymers were characterized using FTIR, TGA, DSC, SEM, XRD, and BET surface area analyses. The incorporation of NDAM directly imparted amine functionality while stabilizing the polysulfide chains by crosslinking, leading to a thermoset copolymer with an amorphous structure. The addition of a NaCl particle porogen to the S/NDAM mixture generated a mesoporous structure, enabling the resulting copolymer to be tested for CO₂ adsorption under varying pressures, leading to an adsorption capacity as high as 517 mg/g at 25 bar. This work not only promotes sustainable hybrid materials that advance green chemistry while aiding CO₂ mitigation efforts but also adds value to the abundant amount of sulfur by-products from petroleum refineries. Full article

A multimethodic approach based on infrared, Raman, electron spin resonance and photoluminescence spectroscopy, absorption spectroscopy in near infrared, visible and ultraviolet regions, single-crystal X-ray diffraction as well as electron microprobe analyses was applied to the characterization of a new commensurately modulated cubic haüyne analogue with the modulation parameter of 0.2 and unit-cell parameter of 45.3629(3) Å (designated as haüyne-45Å) from the Malobystrinskoe lazurite deposit, in the Baikal Lake area, Siberia, Russia, as well as associated SO₃²⁻-bearing afghanite. Haüyne-45Å is the second member, after vladimirivanovite, of the sodalite group with a commensurately modulated structure. The average structure is based on the tetrahedral aluminosilicate sodalite-type framework with sodalite cages of different sizes. The simplified formula of haüyne-45Å is Na₆Ca_2−x(Si₆Al₆O₂₄)(SO₄²⁻,HS⁻,S₂^●−,S₄,S₃^●−,S₅²⁻)_2−y. The structural modulations of the haüyne-45Å framework are presumably related to the regular alternation of SO₄²⁻ anions with polysulfide S₂^●−, S₃^●−, S₄, and S₅²⁻ groups detected by the spectroscopic methods. Mechanisms of thermal conversions of S-bearing groups in haüyne-45Å under oxidizing and reducing conditions at temperatures up to 800 °C are studied, and their geochemical importance is discussed. Full article

Lithium–sulfur batteries (LSBs), possessing excellent theoretical capacities, advanced theoretical energy densities, low cost, and nontoxicity, are one of the most promising energy storage battery systems. However, some issues, including poor conductivity of elemental S, the “shuttle effect” of high-order lithium polysulfides (LiPSs), and sluggish reaction kinetics, hinder the commercialization of LSBs. To solve these problems, various carbon-based aerogels with developed surface morphology, tunable pores, and electrical conductivity have been examined for immobilizing sulfur, mitigating its volume variation and enhancing its electrochemical kinetics. In this paper, an extensive generalization about the effective preparation methods of carbon-based aerogels comprising the combined method of carbonization with the gelation of precursors and drying processes (ambient pressure drying, freeze-drying, and supercritical drying) is proposed. And we summarize various carbon carbon-based aerogels, mainly including graphene aerogels (Gas) and carbon nanofiber (CNF) and carbon nanotube (CNT) aerogels as cathodes, separators, and interlayers in LSBs. In addition, the mechanism of action of carbon-based aerogels in LSBs is described. Finally, we conclude with an outlook section to provide some insights into the application of carbon-based aerogels in electrochemical energy storage devices. Based on the discussion and proposed recommendations, we provide more approaches on nanomaterials in high-performance liquid or state LSBs with high electrochemical performance in the future. Full article

Lithium–sulfur (Li-S) batteries are hindered by the sluggish electrochemical kinetics and poor reversibility of lithium polysulfides (LiPSs), which limits their practical energy density and cycle life. In order to address this issue, a novel Ni₃N/Nb₄N₅ heterostructure was synthesized via electrospinning and nitridation as a functional coating for polypropylene (PP) separators. Adsorption experiments were conducted in order to ascertain the heterostructure’s superior affinity for LiPSs, thereby effectively mitigating their shuttling. Studies of Li₂S nucleation demonstrated the catalytic role of the substance in accelerating the deposition kinetics of Li₂S. Consequently, Li-S cells that employed the Ni₃N/Nb₄N₅-modified separator were found to achieve significantly enhanced electrochemical performance, with the cells delivering an initial discharge capacity of 1294.4 mAh g⁻¹ at 0.2 C. The results demonstrate that, after 150 cycles, the cells retained a discharge capacity of 796.2 mAh g⁻¹, corresponding to a low capacity decay rate of only 0.25% per cycle. In addition, the rate capability of the cells was found to be improved in comparison to control cells with NiNb₂O₆-modified or pristine separators. Full article

Background/Objectives: Dimethyl trisulfide (DMTS) is a naturally occurring polysulfide with known antioxidant and neuroprotective properties. DMTS is a lipophilic transient receptor potential ankyrin 1 (TRPA1) ligand that reaches the central nervous system (CNS). Its role in the CNS, particularly regarding depression-like behaviour, has yet to be explored. This study investigates the influence of DMTS on stress responses and whether this effect is mediated through the TRPA1 ion channel, known for its role in stress adaptation. Using a mouse model involving three-week exposure, we examined the impact of DMTS on depression-like behaviour and anxiety and identified the involved brain regions. Methods: Our methods involved testing both Trpa1-wild-type and gene-knockout mice under CUMS conditions and DMTS treatment. DMTS was administered intraperitoneally at a dose of 30 mg/kg on days 16 and 20 of the 21-day CUMS protocol—in hourly injections seven times to ensure sustained exposure. Various behavioural assessments—including the open field, marble burying, tail suspension, forced swim, and sucrose preference tests—were performed to evaluate anxiety and depression-like behaviour. Additionally, we measured body weight changes and the relative weights of the thymus and adrenal glands, while serum levels of corticosterone and adrenocorticotropic hormone were quantified via ELISA. FOSB (FBJ murine osteosarcoma viral oncogene homolog B) immunohistochemistry was utilised to assess chronic neuronal activation in stress-relevant brain areas. Results: Results showed that CUMS induces depression-like behaviour, with the response being modulated by the TRPA1 status and that DMTS treatment significantly reduced these effects when TRPA1 channels were functional. DMTS also mitigated thymus involution due to hypothalamic–pituitary–adrenal (HPA) axis dysregulation. Conclusions: Overall, DMTS appears to relieve depressive and anxiety symptoms through TRPA1-mediated pathways, suggesting its potential as a dietary supplement or adjunct therapy for depression and anxiety. Full article

This study presents a cost-effective and feasible technique for the deep denitrification of wastewater, based on sulfur autotrophic denitrification mediated by polysulfides (${\mathrm{S}}_{\mathrm{n}}^{2-}$). Various polysulfides were used as electron donors in an aerobic/anoxic sequencing batch reactor (SBR) to simulate nitrification and denitrification processes. The performance of different polysulfide species and their respective dosages were evaluated to determine the optimal conditions for nitrogen removal. Under optimal nitrogen removal conditions with a dosing of 19.2 mg S/L from Na₂S₃, the system was operated continuously for 38 days, with low sludge production during the process. During stable operation, the system achieved an average removal of 7.3 mg/L of $\mathrm{N}{\mathrm{O}}_3^{-}\text{-}\mathrm{N}$, corresponding to a removal efficiency of 23.1%. No significant accumulation of $\mathrm{N}{\mathrm{O}}_2^{-}\text{-}\mathrm{N}$ was observed in the effluent, and the average utilization efficiency of Na₂S₃ reached 83.7%. Continuous dosing of Na₂S₃ promoted the enrichment of sulfur autotrophic denitrification-related microorganisms within the system. Full article