Journal articles: 'Polysulfide'

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Goifman, A., D. Ryzkov, J. Gun, A. Kamyshny, A. D. Modestov, and O. Lev. "Inorganic polysulfides’ quantitation by methyl iodide derivatization: dimethylpolysulfide formation potential." Water Science and Technology 49, no. 9 (May 1, 2004): 179–84. http://dx.doi.org/10.2166/wst.2004.0565.

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Inorganic polysulfides are important intermediates in the formation of dimethylpolysulfides and possibly other volatile sulfur compounds of environmental significance. Currently, direct determination of these ions in the concentration range of natural systems is practically impossible, particularly under oxic conditions. Polysulfide quantification by derivatization with methyl iodide or d6-methyl iodide is emerging as a valuable alternative method for studies of polysulfide formation in natural systems. This manuscript presents detailed studies aimed at the evaluation of this method. We determined the conversion of the inorganic polysulfides to dimethylpolysulfides by methylation with methyl iodide. Close to 100 per cent of the molar concentration of polysulfide salts were converted to organic polysulfides for very low concentrations of dissolved polysulfide solutions, but only a small recovery was obtained for high concentrations of polysulfide precursors or when the solubility limit was exceeded. The recovery of polysulfides based on the calculated dissolved polysulfide concentration exceeds 1,000 per cent for very low dissolved concentrations of polysulfides. This unexpected dependence is attributed to continuous inorganic polysulfide formation from hydrogen sulfide and sulfur precipitate concurrent with, and in fact driven by, the methylation process.

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Choi, Wonmun, and Tomoyuki Matsumura. "Synthesis of Cyclic Polysulfides and their Properties as Curing Agents." Rubber Chemistry and Technology 77, no. 2 (May 1, 2004): 380–90. http://dx.doi.org/10.5254/1.3547830.

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Abstract The reactions of dichloroalkanes and sodium tetra-sulfide (Na2S4) were carried out in a mixture of water and toluene to produce corresponding cyclic polysulfides and polysulfide polymer. The low molecular weights of cyclic sulfides were obtained by the reaction at 90 °C, while the high molecular weight of polysulfide polymer was obtained by the reaction at 50 °C. GPC chromatograms and Mass spectra revealed that the structures of cyclic polysulfide were 1:1, 2:2, and 3:3 adducts of dichloroalkane and sodium tetra-sulfide. The mechanical properties of vulcanized NR at 148 °C with cyclic sulfides were similar to that with sulfur. However, both tensile strength and elongation at break of vulcanized NR at 170 °C with cyclic sulfides are much higher than that with sulfur. The aging properties of vulcanized NR at 148 °C or 170 °C with cyclic polysulfides indicate better stability.

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Yu, Xingwen, and Arumugam Manthiram. "A class of polysulfide catholytes for lithium–sulfur batteries: energy density, cyclability, and voltage enhancement." Physical Chemistry Chemical Physics 17, no. 3 (2015): 2127–36. http://dx.doi.org/10.1039/c4cp04895d.

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Chauvin, Jean-Philippe R., Evan A. Haidasz, Markus Griesser, and Derek A. Pratt. "Polysulfide-1-oxides react with peroxyl radicals as quickly as hindered phenolic antioxidants and do so by a surprising concerted homolytic substitution." Chemical Science 7, no. 10 (2016): 6347–56. http://dx.doi.org/10.1039/c6sc01434h.

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Chang, Caiyun, and Xiong Pu. "Revisiting the positive roles of liquid polysulfides in alkali metal–sulfur electrochemistry: from electrolyte additives to active catholyte." Nanoscale 11, no. 45 (2019): 21595–621. http://dx.doi.org/10.1039/c9nr07416c.

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Yin, Shujun, Chenhui Wei, and Dongqiang Zhu. "Surface quinone-induced formation of aqueous reactive sulfur species controls pine wood biochar-mediated reductive dechlorination of hexachloroethane by sulfide." Environmental Science: Processes & Impacts 22, no. 9 (2020): 1898–907. http://dx.doi.org/10.1039/d0em00307g.

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Xu, Guiyin, Qing-bo Yan, Shitong Wang, Akihiro Kushima, Peng Bai, Kai Liu, Xiaogang Zhang, Zilong Tang, and Ju Li. "A thin multifunctional coating on a separator improves the cyclability and safety of lithium sulfur batteries." Chemical Science 8, no. 9 (2017): 6619–25. http://dx.doi.org/10.1039/c7sc01961k.

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Xu, Jing, Dawei Su, Wenxue Zhang, Weizhai Bao, and Guoxiu Wang. "A nitrogen–sulfur co-doped porous graphene matrix as a sulfur immobilizer for high performance lithium–sulfur batteries." Journal of Materials Chemistry A 4, no. 44 (2016): 17381–93. http://dx.doi.org/10.1039/c6ta05878g.

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The combination of the physical adsorption of lithium polysulfides onto porous graphene and the chemical binding of polysulfides to N and S sites promotes reversible Li₂S/polysulfide/S conversion, realizing high performance Li–S batteries with long cycle life and high-energy density.

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Dagnell, Markus, Qing Cheng, and Elias S. J. Arnér. "Qualitative Differences in Protection of PTP1B Activity by the Reductive Trx1 or TRP14 Enzyme Systems upon Oxidative Challenges with Polysulfides or H2O2 Together with Bicarbonate." Antioxidants 10, no. 1 (January 14, 2021): 111. http://dx.doi.org/10.3390/antiox10010111.

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Protein tyrosine phosphatases (PTPs) can be regulated by several redox-dependent mechanisms and control growth factor-activated receptor tyrosine kinase phosphorylation cascades. Reversible oxidation of PTPs is counteracted by reductive enzymes, including thioredoxin (Trx) and Trx-related protein of 14 kDa (TRP14), keeping PTPs in their reduced active states. Different modes of oxidative inactivation of PTPs concomitant with assessment of activating reduction have been little studied in direct comparative analyses. Determining PTP1B activities, we here compared the potency of inactivation by bicarbonate-assisted oxidation using H2O2 with that of polysulfide-mediated inactivation. Inactivation of pure PTP1B was about three times more efficient with polysulfides as compared to the combination of bicarbonate and H2O2. Bicarbonate alone had no effect on PTP1B, neither with nor without a combination with polysulfides, thus strengthening the notion that bicarbonate-assisted H2O2-mediated inactivation of PTP1B involves formation of peroxymonocarbonate. Furthermore, PTP1B was potently protected from polysulfide-mediated inactivation by either TRP14 or Trx1, in contrast to the inactivation by bicarbonate and H2O2. Comparing reductive activation of polysulfide-inactivated PTP1B with that of bicarbonate- and H2O2-treated enzyme, we found Trx1 to be more potent in reactivation than TRP14. Altogether we conclude that inactivation of PTP1B by polysulfides displays striking qualitative differences compared to that by H2O2 together with bicarbonate, also with regard to maintenance of PTP1B activity by either Trx1 or TRP14.

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Shah, Vaidik, and Yong Lak Joo. "Incorporation of Functionalized Graphene and Its Derivates into Electrolyte: A Facile Approach to Improve the Electrochemical Performance of Lithium-Sulfur Batteries." ECS Meeting Abstracts MA2022-01, no. 1 (July 7, 2022): 82. http://dx.doi.org/10.1149/ma2022-01182mtgabs.

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The impending global energy crisis and the severe environmental problems in the recent years has bolstered the research for sustainable electrochemical energy storage. With the lithium-ion technology reaching its theoretical limit, lithium sulfur (Li-S) batteries have garnered extensive attention owing to their ultrahigh theoretical capacity and the low-cost, Earth abundant and environmentally friendly nature of the sulfur cathode. Despite all the advantages, the development of Li-S technology is hindered by several inherent challenges namely, the large capacity drain due to the dissolution of the intermediate polysulfides in the electrolyte leading to polysulfide shuttling and low conductivity in the cell. To overcome these issues, graphene and its derivatives have been extensively explored to mitigate polysulfide shuttling and enhance conductivity in the cell. However, at present, most of this research is limited to cathode modification which despite improving capacity retention is unable to curb the deleterious impact of polysulfide shuttling once the polysulfides dissolve in the electrolyte. In this work, we have probed the impact of implementing graphene and its derivatives as additives to the Li-S electrolyte. We have extensively characterized various commercially available rGO and graphene samples to determine their morphology, functionalization, and other key ancillary properties such as defects and ionic resistivity and have studied their impact towards the electrochemical performance of the electrolyte-modified Li-S cell. Results showed a marked improvement in initial capacity of 1323 mAh/gs and a capacity retention of 83% at 0.2 C over 105 cycles with single layer graphene additive. Further, it was shown that increasing functionalization led to improved mitigation of polysulfide shuttling and about 20% higher capacity retention (than reference) over 105 cycles. The impact of different functional groups on graphene was also probed to compare their polysulfide shuttling mitigation capacity in the electrolyte. Overall, we successfully achieved superior electrochemical performance of the Li-S cell simply by addition of graphene to the electrolyte. It was successfully shown that functionalized graphene dispersed in the electrolyte can enhance polysulfide encapsulation and improve the ionic conductivity in the cell.

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Abdouss, M., T. Farajpour, and M. Derakhshani. "Investigating of polysulfide and epoxy-polysulfide copolymer curing. Untersuchungen zur Copolymer-Aushärtung von Polysulfiden und Epoxy-Polysulfiden." Materialwissenschaft und Werkstofftechnik 41, no. 10 (October 2010): 884–88. http://dx.doi.org/10.1002/mawe.201000680.

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Boyd, Eric S., and Gregory K. Druschel. "Involvement of Intermediate Sulfur Species in Biological Reduction of Elemental Sulfur under Acidic, Hydrothermal Conditions." Applied and Environmental Microbiology 79, no. 6 (January 18, 2013): 2061–68. http://dx.doi.org/10.1128/aem.03160-12.

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ABSTRACTThe thermoacidophile and obligate elemental sulfur (S80)-reducing anaerobeAcidilobus sulfurireducens18D70 does not associate with bulk solid-phase sulfur during S80-dependent batch culture growth. Cyclic voltammetry indicated the production of hydrogen sulfide (H2S) as well as polysulfides after 1 day of batch growth of the organism at pH 3.0 and 81°C. The production of polysulfide is likely due to the abiotic reaction between S80and the biologically produced H2S, as evinced by a rapid cessation of polysulfide formation when the growth temperature was decreased, inhibiting the biological production of sulfide. After an additional 5 days of growth, nanoparticulate S80was detected in the cultivation medium, a result of the hydrolysis of polysulfides in acidic medium. To examine whether soluble polysulfides and/or nanoparticulate S80can serve as terminal electron acceptors (TEA) supporting the growth ofA. sulfurireducens, total sulfide concentration and cell density were monitored in batch cultures with S80provided as a solid phase in the medium or with S80sequestered in dialysis tubing. The rates of sulfide production in 7-day-old cultures with S80sequestered in dialysis tubing with pore sizes of 12 to 14 kDa and 6 to 8 kDa were 55% and 22%, respectively, of that of cultures with S80provided as a solid phase in the medium. These results indicate that the TEA existed in a range of particle sizes that affected its ability to diffuse through dialysis tubing of different pore sizes. Dynamic light scattering revealed that S80particles generated through polysulfide rapidly grew in size, a rate which was influenced by the pH of the medium and the presence of organic carbon. Thus, S80particles formed through abiological hydrolysis of polysulfide under acidic conditions appeared to serve as a growth-promoting TEA forA. sulfurireducens.

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Olson, Kenneth R., Yan Gao, and Karl D. Straub. "Oxidation of Hydrogen Sulfide by Quinones: How Polyphenols Initiate Their Cytoprotective Effects." International Journal of Molecular Sciences 22, no. 2 (January 19, 2021): 961. http://dx.doi.org/10.3390/ijms22020961.

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We have shown that autoxidized polyphenolic nutraceuticals oxidize H2S to polysulfides and thiosulfate and this may convey their cytoprotective effects. Polyphenol reactivity is largely attributed to the B ring, which is usually a form of hydroxyquinone (HQ). Here, we examine the effects of HQs on sulfur metabolism using H2S- and polysulfide-specific fluorophores (AzMC and SSP4, respectively) and thiosulfate sensitive silver nanoparticles (AgNP). In buffer, 1,4-dihydroxybenzene (1,4-DB), 1,4-benzoquinone (1,4-BQ), pyrogallol (PG) and gallic acid (GA) oxidized H2S to polysulfides and thiosulfate, whereas 1,2-DB, 1,3-DB, 1,2-dihydroxy,3,4-benzoquinone and shikimic acid did not. In addition, 1,4-DB, 1,4-BQ, PG and GA also increased polysulfide production in HEK293 cells. In buffer, H2S oxidation by 1,4-DB was oxygen-dependent, partially inhibited by tempol and trolox, and absorbance spectra were consistent with redox cycling between HQ autoxidation and H2S-mediated reduction. Neither 1,2-DB, 1,3-DB, 1,4-DB nor 1,4-BQ reduced polysulfides to H2S in either 21% or 0% oxygen. Epinephrine and norepinephrine also oxidized H2S to polysulfides and thiosulfate; dopamine and tyrosine were ineffective. Polyphenones were also examined, but only 2,5-dihydroxy- and 2,3,4-trihydroxybenzophenones oxidized H2S. These results show that H2S is readily oxidized by specific hydroxyquinones and quinones, most likely through the formation of a semiquinone radical intermediate derived from either reaction of oxygen with the reduced quinones, or from direct reaction between H2S and quinones. We propose that polysulfide production by these reactions contributes to the health-promoting benefits of polyphenolic nutraceuticals.

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Yan, Min, Yang Zhang, Yu Li, Yongqi Huo, Yong Yu, Chao Wang, Jun Jin, et al. "Manganese dioxide nanosheet functionalized sulfur@PEDOT core–shell nanospheres for advanced lithium–sulfur batteries." Journal of Materials Chemistry A 4, no. 24 (2016): 9403–12. http://dx.doi.org/10.1039/c6ta03211g.

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MnO₂ nanosheet functionalized S@PEDOT core–shell nanospheres demonstrate highly enhanced electrochemical performance for Li–S batteries, benefitting from effectively trapping polysulfides, minimizing polysulfide dissolution, and improving cathode conductivity and wettability.

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Azam, Sakibul, and Ruigang Wang. "Novel Adsorption-Catalysis Design of CuO Impregnated CeO₂ Nanorods As Cathode Modifier for Lithium-Sulfur Battery." ECS Meeting Abstracts MA2022-02, no. 2 (October 9, 2022): 133. http://dx.doi.org/10.1149/ma2022-022133mtgabs.

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Lithium sulfur batteries (LSBs) are a promising candidate to be used in modern commodities like electric vehicles, grid energy storage, electric aviation, and many others because of the exceptionally high theoretical capacity of sulfur (1675 mAh g-1), almost 5 times higher than the conventional lithium-ion batteries. However, the problem of polysulfide shuttling effect originating from the dissolved lithium polysulfides in the electrolyte results in poor cycling stability, hindering the commercialization of LSB. Significant advancement has been made over the years due to a great deal of research on novel materials development and structural design for lithium polysulfide (Li2Sn: 4≤ n ≤8) adsorption synergy to counter the polysulfide shuttling effect 1. However, rather than focusing only on the adsorption synergy (Physical confinement and chemical binding), novel catalysts that can accelerate the polysulfide conversion reaction kinetics are needed to design the next generation LSB. Previously, our group investigated shape-controlled cerium oxide (CeO2) to accelerate the polysulfide conversion reactions by generating the intermediate steps of thiosulfate and polythionate 2, 3. Copper oxide (CuO), being a p-type semiconducting material, is another promising material that can activate thiosulfate formation as its redox potential is 2.53 V vs Li/Li+, which lies in the potential window of 2.4 V < E° ≤ 3.05 V that selectively triggers the formation of thiosulfate. Herein, we investigated 10 wt% of CuO impregnated on the CeO2 nanorods (10 wt%CuO/CeO2) as a cathode host for LSB. The CuO impregnation on the surface of CeO2 nanorods attributed strong interaction between the surface defect rich CeO2 nanorods and the copper oxides (CuOx: Cu2O and CuO) promoting excellent electrocatalytic activity. The 10 wt%CuO/CeO2 sample provides adsorption-catalysis dual synergy to chemically bind and further catalyze the polysulfide conversion by polythionate and thiosulfate generation. As a result, the derived LSB exhibited excellent electrochemical performance with high capacity of 1141 mAh g-1 at 0.2 C with a sulfur loading of 1.33 mg cm-2 and a capacity loss of only 0.04% per cycle after 60 cycles. Key words: lithium sulfur batteries, lithium polysulfides, shuttle effect, cerium oxide, catalysis. Xiong, D. G.; Zhang, Z.; Huang, X. Y.; Huang, Y.; Yu, J.; Cai, J. X.; Yang, Z. Y., Boosting the polysulfide confinement in B/N–codoped hierarchically porous carbon nanosheets via Lewis acid–base interaction for stable Li–S batteries. Journal of Energy Chemistry 2020, 51, 90-100. Azam, S.; Wei, Z.; Wang, R., Cerium oxide nanorods anchored on carbon nanofibers derived from cellulose paper as effective interlayer for lithium sulfur battery. J Colloid Interface Sci 2022, 615, 417-431. Wei, Z.; Li, J.; Wang, R., Surface engineered polar CeO2-based cathode host materials for immobilizing lithium polysulfides in High-performance Li-S batteries. Applied Surface Science 2022, 580.

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Wręczycki, Jakub, Dariusz M. Bieliński, Marcin Kozanecki, Paulina Maczugowska, and Grzegorz Mlostoń. "Anionic Copolymerization of Styrene Sulfide with Elemental Sulfur (S8)." Materials 13, no. 11 (June 7, 2020): 2597. http://dx.doi.org/10.3390/ma13112597.

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The superior ability of thiiranes (episulfides) to undergo ring-opening polymerization (ROP) in the presence of anionic initiators allows the preparation of chemically stable polysulfide homopolymers. Incorporation of elemental sulfur (S8) by copolymerization below the floor temperature of S8 permits the placement of a large quantity of sulfur atoms in the polysulfide mainchain. The utility of styrene sulfide (2-phenylthiirane; StS) for copolymerization with elemental sulfur is reported here. A few polysulfides differing depending on the initial ratio of S8 to StS and copolymerization time were synthesized. Various spectroscopic methods (1H NMR, 13C NMR, Raman spectroscopy and FTIR spectroscopy) were applied to characterize the chemical structure of the copolymers. Additionally, the phase structure and thermal stability of the synthesized polysulfides were investigated using DSC and TGA, respectively. The successful anionic copolymerization of styrene sulfide and elemental sulfur has been demonstrated.

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Tripathi, Balram, Rajesh K. Katiyar, Gerardo Morell, Ambesh Dixit, and Ram S. Katiyar. "BiFeO3 Coupled Polysulfide Trapping in C/S Composite Cathode Material for Li-S Batteries as Large Efficiency and High Rate Performance." Energies 14, no. 24 (December 11, 2021): 8362. http://dx.doi.org/10.3390/en14248362.

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We demonstrated the efficient coupling of BiFeO3 (BFO) ferroelectric material within the carbon–sulfur (C-S) composite cathode, where polysulfides are trapped in BFO mesh, reducing the polysulfide shuttle impact, and thus resulting in an improved cyclic performance and an increase in capacity in Li-S batteries. Here, the built-in internal field due to BFO enhances polysulfide trapping. The observation of a difference in the diffusion behavior of polysulfides in BFO-coupled composites suggests more efficient trapping in BFO-modified C-S electrodes compared to pristine C-S composite cathodes. The X-ray diffraction results of BFO–C-S composite cathodes show an orthorhombic structure, while Raman spectra substantiate efficient coupling of BFO in C-S composites, in agreement with SEM images, showing the interconnected network of submicron-size sulfur composites. Two plateaus were observed at 1.75 V and 2.1 V in the charge/discharge characteristics of BFO–C-S composite cathodes. The observed capacity of ~1600 mAh g−1 in a 1.5–2.5 V operating window for BFO30-C10-S60 composite cathodes, and the high cyclic stability substantiate the superior performance of the designed cathode materials due to the efficient reduction in the polysulfide shuttle effect in these composite cathodes.

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Jay, Jenny Ayla, Karen J. Murray, Cynthia C. Gilmour, Robert P. Mason, François M. M. Morel, A. Lynn Roberts, and Harold F. Hemond. "Mercury Methylation by Desulfovibrio desulfuricans ND132 in the Presence of Polysulfides." Applied and Environmental Microbiology 68, no. 11 (November 2002): 5741–45. http://dx.doi.org/10.1128/aem.68.11.5741-5745.2002.

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ABSTRACT The extracellular speciation of mercury may control bacterial uptake and methylation. Mercury-polysulfide complexes have recently been shown to be prevalent in sulfidic waters containing zero-valent sulfur. Despite substantial increases in total dissolved mercury concentration, methylation rates in cultures of Desulfovibrio desulfuricans ND132 equilibrated with cinnabar did not increase in the presence of polysulfides, as expected due to the large size and charged nature of most of the complexes. In natural waters not at saturation with cinnabar, mercury-polysulfide complexes would be expected to shift the speciation of mercury from HgS0 (aq) toward charged complexes, thereby decreasing methylation rates.

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He, Jiarui, Gregory Hartmann, Myungsuk Lee, Gyeong S. Hwang, Yuanfu Chen, and Arumugam Manthiram. "Freestanding 1T MoS2/graphene heterostructures as a highly efficient electrocatalyst for lithium polysulfides in Li–S batteries." Energy & Environmental Science 12, no. 1 (2019): 344–50. http://dx.doi.org/10.1039/c8ee03252a.

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A novel approach to effectively suppress the “polysulfide shuttle” in Li–S batteries is presented by designing a freestanding, three-dimensional graphene/1T MoS₂ (3DG/TM) heterostructure with highly efficient electrocatalysis properties for lithium polysulfides (LiPSs).

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Ahad, Syed Abdul, P. Ragupathy, Soojy Ryu, Hyun-Wook Lee, and Do Kyung Kim. "Unveiling the synergistic effect of polysulfide additive and MnO2 hollow spheres in evolving a stable cyclic performance in Li–S batteries." Chemical Communications 53, no. 62 (2017): 8782–85. http://dx.doi.org/10.1039/c7cc04229a.

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The inbuilt MnO₂ hollow spheres trap polysulfides effectively, while the polysulfide additive provides mass buffering to compensate for the capacity loss and prevent the formation of Li₂S exhibiting excellent rate capability and cycling stability.

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Salpekar, Devashish, Changxin Dong, Eliezer F. Oliveira, Valery N. Khabashesku, Guanhui Gao, Ved Ojha, Robert Vajtai, Douglas S. Galvao, Ganguli Babu, and Pulickel M. Ajayan. "Fluorinated Multi-Walled Carbon Nanotubes Coated Separator Mitigates Polysulfide Shuttle in Lithium-Sulfur Batteries." Materials 16, no. 5 (February 22, 2023): 1804. http://dx.doi.org/10.3390/ma16051804.

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Li-S batteries still suffer from two of the major challenges: polysulfide shuttle and low inherent conductivity of sulfur. Here, we report a facile way to develop a bifunctional separator coated with fluorinated multiwalled carbon nanotubes. Mild fluorination does not affect the inherent graphitic structure of carbon nanotubes as shown by transmission electron microscopy. Fluorinated carbon nanotubes show an improved capacity retention by trapping/repelling lithium polysulfides at the cathode, while simultaneously acting as the “second current collector”. Moreover, reduced charge-transfer resistance and enhanced electrochemical performance at the cathode-separator interface result in a high gravimetric capacity of around 670 mAh g−1 at 4C. Unique chemical interactions between fluorine and carbon at the separator and the polysulfides, studied using DFT calculations, establish a new direction of utilizing highly electronegative fluorine moieties and absorption-based porous carbons for mitigation of polysulfide shuttle in Li-S batteries.

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Weret, Misganaw Adigo, Wei-Nien Su, and Bing-Joe Hwang. "Organosulfur Cathodes with High Compatibility in Carbonate Ester Electrolytes for Long Cycle Lithium–Sulfur Batteries." ECS Meeting Abstracts MA2022-02, no. 4 (October 9, 2022): 536. http://dx.doi.org/10.1149/ma2022-024536mtgabs.

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Lithium-sulfur batteries (LSBs) are potential candidates for high energy storage technologies due to their theoretical gravimetric energy density of ∼2600 Wh kg-1 and lightweight electrodes. In LSBs, ether electrolytes are frequently utilized because sulfur cathodes and the polysulfide redox intermediate species are chemically stable. However, LSBs in ether electrolytes suffer from the dissolution of higher-order polysulfides, and migration of the soluble polysulfides into electrolytes causes the polysulfide shuttle effect. The shuttle polysulfides react with the lithium anode and give rise to the irreversible deposition of lithium sulfides, deteriorate the morphology of the anode, and cause rapid capacity fading. Moreover, ether electrolytes are highly flammable and trigger safety issues. As an alternative, carbonate ester electrolytes are promising choices to substitute ether electrolytes in LSBs. Organic carbonate electrolytes used in LSBs result in irreversible reactions with long-chain polysulfide anions that cause the cell to shut down. Therefore, carbonate ester electrolytes compatible sulfur cathodes design needs special attention. Sulfurized polyacrylonitrile (SPAN) and short-chain sulfur cathodes are compatible with organic carbonate electrolytes. However, the sulfur contents in these cathodes are mostly below 50 wt% which hamper the practical application of the LSBs. Here, we designed an organosulfur cathode with a high chemical bonded sulfur content of ~58 wt% in the cathode composite. The prepared organosulfur cathode showed excellent compatibility with carbonate ester electrolytes. The organosulfur cathode exhibits a high initial discharge capacity of 1301 mAh g-1 and long cycle stability for 400 cycles with nearly 99.99% coulombic efficiency.

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Klorman, Jake A., Qing Guo, and Kah Chun Lau. "First-Principles Study of Amorphous Al2O3 ALD Coating in Li-S Battery Electrode Design." Energies 15, no. 1 (January 5, 2022): 390. http://dx.doi.org/10.3390/en15010390.

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The Li-S battery is exceptionally appealing as an alternative candidate beyond Li-ion battery technology due to its promising high specific energy capacity. However, several obstacles (e.g., polysulfides’ dissolution, shuttle effect, high volume expansion of cathode, etc.) remain and thus hinder the commercialization of the Li-S battery. To overcome these challenges, a fundamental study based on atomistic simulation could be very useful. In this work, a comprehensive investigation of the adsorption of electrolyte (solvent and salt) molecules, lithium sulfide, and polysulfide (Li2Sx with 2 ≤x≤ 8) molecules on the amorphous Al2O3 atomic layer deposition (ALD) surface was performed using first-principles density functional theory (DFT) calculations. The DFT results indicate that the amorphous Al2O3 ALD surface is selective in chemical adsorption towards lithium sulfide and polysulfide molecules compared to electrolytes. Based on this work, it suggests that the Al2O3 ALD is a promising coating material for Li-S battery electrodes to mitigate the shuttling problem of soluble polysulfides.

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Wang, Maoxu, Lishuang Fan, Xian Wu, Yue Qiu, Bin Guan, Yan Wang, Naiqing Zhang, and Kening Sun. "Metallic NiSe2nanoarrays towards ultralong life and fast Li2S oxidation kinetics of Li–S batteries." Journal of Materials Chemistry A 7, no. 25 (2019): 15302–8. http://dx.doi.org/10.1039/c9ta03361k.

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The complex solid–liquid–solid phase transition in Li–S batteries, the serious shuttle effect of soluble polysulfides, sluggish polysulfide conversion kinetics and the low conductive nature of Li₂S cause a high decomposition barrier, inevitably limiting the development of advanced Li–S batteries.

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Djordjevic, Dragana, Jelena Milovanovic, Milena Jurisevic, Bojana Stojanovic, Olga Cvetkovic, Marija Pergal, Elizabeta Ristanovic, et al. "Antitumour Effect of a Mixture of N-Propyl Polysulfides In Vitro." Serbian Journal of Experimental and Clinical Research 20, no. 4 (December 31, 2019): 295–300. http://dx.doi.org/10.1515/sjecr-2017-0069.

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Abstract Copper serves as a limiting factor for multiple steps of tumour progression, including angiogenesis, growth and metastasis. High levels of copper have been found in a wide spectrum of human cancers. Antitumour activities of copper-chelating drugs have been reported in animal models. Organosulfur compounds (diallyl sulfide, DAS; diallyl disulfide, DADS; S-ethylcysteine, SEC; N-acetylcysteine, NAC) derived from garlic exhibit marked copper-chelating activity. We analysed a mixture of fifteen n-propyl polysulfides (DPPS) for potential antitumour activity against several murine tumour cell lines, including colon carcinoma (CT26), mammary carcinoma (4T1) and melanoma cell lines (B16F10), and compared the effects with the antiproliferative effect in highly proliferative murine mesenchymal stem cells (mMSCs). The effects of the mixture of n-propyl polysulfides (100%) on cell viability were determined using MTT assays. Cell apoptosis was analysed using Annexin V-FITC/PI assays. The results of the MTT assays indicate that this standardized mixture of n-propyl polysulfides has a strong, dose-dependent cytotoxic effect against all three of the tested tumour cell lines (CT26, 4T1, B16F10). The cytotoxic effect of the n-propyl polysulfide mixture against the CT26 and B16F10 cell lines was much stronger than that of cisplatin and was significantly weaker in mMSCs, which are non-cancerous and highly proliferative cells, than in cancer cells. Flow cytometric analysis of CT26 and 4T1 cells revealed that apoptosis was not the dominant mechanism of cell death induced by the n-propyl polysulfide mixture. The n-propyl polysulfide mixture exerted highly cytotoxic activity against murine colon carcinoma and melanoma cell lines, but its antiproliferative activity against mMSCs was significantly lower than that of cisplatin.

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Infante Teixeira, Lorena, Katharina Landfester, and Héloïse Thérien-Aubin. "Selective Oxidation of Polysulfide Latexes to Produce Polysulfoxide and Polysulfone in a Waterborne Environment." Macromolecules 54, no. 8 (April 8, 2021): 3659–67. http://dx.doi.org/10.1021/acs.macromol.1c00382.

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Trummer, Modesta, Erwan Galardon, Anita Fischer, Stefan Toegel, Bernhard-Michael Mayer, Guenter Steiner, and Burkhard Kloesch. "Characterization of the Inducible and Slow-Releasing Hydrogen Sulfide and Persulfide Donor P*: Insights into Hydrogen Sulfide Signaling." Antioxidants 10, no. 7 (June 29, 2021): 1049. http://dx.doi.org/10.3390/antiox10071049.

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Hydrogen sulfide (H2S) is an important mediator of inflammatory processes. However, controversial findings also exist, and its underlying molecular mechanisms are largely unknown. Recently, the byproducts of H2S, per-/polysulfides, emerged as biological mediators themselves, highlighting the complex chemistry of H2S. In this study, we characterized the biological effects of P*, a slow-releasing H2S and persulfide donor. To differentiate between H2S and polysulfide-derived effects, we decomposed P* into polysulfides. P* was further compared to the commonly used fast-releasing H2S donor sodium hydrogen sulfide (NaHS). The effects on oxidative stress and interleukin-6 (IL-6) expression were assessed in ATDC5 cells using superoxide measurement, qPCR, ELISA, and Western blotting. The findings on IL-6 expression were corroborated in primary chondrocytes from osteoarthritis patients. In ATDC5 cells, P* not only induced the expression of the antioxidant enzyme heme oxygenase-1 via per-/polysulfides, but also induced activation of Akt and p38 MAPK. NaHS and P* significantly impaired menadione-induced superoxide production. P* reduced IL-6 levels in both ATDC5 cells and primary chondrocytes dependent on H2S release. Taken together, P* provides a valuable research tool for the investigation of H2S and per-/polysulfide signaling. These data demonstrate the importance of not only H2S, but also per-/polysulfides as bioactive signaling molecules with potent anti-inflammatory and, in particular, antioxidant properties.

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Hahn, J., P. Palloch, N. Thelen, and H.-J. Weidenhaupt. "Reversion Stable Networks with Polysulfide Polymers as Vulcanization Agents." Rubber Chemistry and Technology 74, no. 1 (March 1, 2001): 28–43. http://dx.doi.org/10.5254/1.3547637.

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Abstract To study the network structure generated by the polysulfide polymer [[(CH2)2S4]p as a crosslinking agent, model compound vulcanization with 2,3-dimethyl-2-butene as the model alkene was carried out. It was found that the polysulfide polymer generates hybrid bridges of the general constitution Sn−(CH2CH2−Sm)k(n=1−4,m=1−4,k=1−6). To a lesser extent the polysulfide polymer behaves as a sulfur donor generating conventional sulfur bridges Sx(x=1−5). Polysulfidic bridges (x=4, 5) were only detected in the very early stage of network formation. The process of network formation and the development of the bridges during prolonged heating was monitored by 1H NMR spectroscopy and compared with that of a sulfur cure. In the case of the polysulfide polymer cure the early network contained a relatively high amount of mono-and disulfidic bridges and a stable network was formed after at least 60 min of heating (150 °C). This effect results from the higher thermal stability of hybrid bridges in comparison to conventional sulfur bridges. The higher stability of the hybrid bridges also leads to a suppression of the formation of 3,4-dimethylthiophene which has been identified in the sulfur cure as a product of reversion processes. Thus, the increased reversion stability of polysulfide polymer cures, which has been claimed earlier, can be related to the formation and the increased stability of the hybrid bridges.

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29

Braunstein, Ilana, Rotem Engelman, Ofer Yitzhaki, Tamar Ziv, Erwan Galardon, and Moran Benhar. "Opposing effects of polysulfides and thioredoxin on apoptosis through caspase persulfidation." Journal of Biological Chemistry 295, no. 11 (February 10, 2020): 3590–600. http://dx.doi.org/10.1074/jbc.ra119.012357.

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Hydrogen sulfide has been implicated in a large number of physiological processes including cell survival and death, encouraging research into its mechanisms of action and therapeutic potential. Results from recent studies suggest that the cellular effects of hydrogen sulfide are mediated in part by sulfane sulfur species, including persulfides and polysulfides. In the present study, we investigated the apoptosis-modulating effects of polysulfides, especially on the caspase cascade, which mediates the intrinsic apoptotic pathway. Biochemical analyses revealed that organic or synthetic polysulfides strongly and rapidly inhibit the enzymatic activity of caspase-3, a major effector protease in apoptosis. We attributed the caspase-3 inhibition to persulfidation of its catalytic cysteine. In apoptotically stimulated HeLa cells, short-term exposure to polysulfides triggered the persulfidation and deactivation of cleaved caspase-3. These effects were antagonized by the thioredoxin/thioredoxin reductase system (Trx/TrxR). Trx/TrxR restored the activity of polysulfide-inactivated caspase-3 in vitro, and TrxR inhibition potentiated polysulfide-mediated suppression of caspase-3 activity in situ. We further found that under conditions of low TrxR activity, early cell exposure to polysulfides leads to enhanced persulfidation of initiator caspase-9 and decreases apoptosis. Notably, we show that the proenzymes procaspase-3 and -9 are basally persulfidated in resting (unstimulated) cells and become depersulfidated during their processing and activation. Inhibition of TrxR attenuated the depersulfidation and activation of caspase-9. Taken together, our results reveal that polysulfides target the caspase-9/3 cascade and thereby suppress cancer cell apoptosis, and highlight the role of Trx/TrxR-mediated depersulfidation in enabling caspase activation.

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30

Yang, Bin, Zengyue Wang, Wanwan Wang, and Yi-Chun Lu. "A Low-Crossover and Fast-Kinetics Thiolate Negolyte for Aqueous Redox Flow Batteries." Energy Material Advances 2022 (January 4, 2022): 1–11. http://dx.doi.org/10.34133/2022/9795675.

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Aqueous redox flow batteries (ARFBs) are a promising technology for large-scale energy storage. Developing high-capacity and long-cycle negolyte materials is one of major challenges for practical ARFBs. Inorganic polysulfide is promising for ARFBs owing to its low cost and high solubility. However, it suffers from severe crossover resulting in low coulombic efficiency and limited lifespan. Organosulfides are more resistant to crossover than polysulfides owing to their bulky structures, but they suffer from slow reaction kinetics. Herein, we report a thiolate negolyte prepared by an exchange reaction between a polysulfide and an organosulfide, preserving low crossover rate of the organosulfide and high reaction kinetics of the polysulfide. The thiolate denoted as 2-hydroxyethyl disulfide+potassium polysulfide (HEDS+K2S2) shows reduced crossover rate than K2S2, faster reaction kinetics than HEDS, and longer lifespan than both HEDS and K2S2. The 1.5 M HEDS+1.5 M K2S2 static cell demonstrated 96 Ah L-1negolyte over 100 and 200 cycles with a high coulombic efficiency of 99.2% and 99.6% at 15 and 25 mA cm-2, respectively. The 0.5 M HEDS+0.5 M K2S2 flow cell delivered a stable and high capacity of 30.7 Ah L-1negolyte over 400 cycles (691 h) at 20 mA cm-2. This study presents an effective strategy to enable low-crossover and fast-kinetics sulfur-based negolytes for advanced ARFBs.

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Nikman, Shahin, Abdulhakim Oudjana, Thomas Leckie, Pasidu Pallawela, and Edward Brightman. "Hybrid Lithium Polysulfide Flow Batteries for Large Scale Energy Storage." ECS Meeting Abstracts MA2022-02, no. 2 (October 9, 2022): 139. http://dx.doi.org/10.1149/ma2022-022139mtgabs.

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Lithium-sulfur battery chemistry has garnered global attention as a promising next-generation energy storage technology due to its significantly higher theoretical capacity (450 Wh/kg) compared to lithium-ion (265 Wh/kg), and the fact that its elemental components are green, safe and abundant[1]. As opposed to lithium-ion, the cathode solution chemistry is rich, as elemental sulfur forms polysulfide chains during discharge which can transport and deposit on the metallic lithium anode during a dissolution-migration-deposition “shuttle” mechanism which in effect a) cause a constant internal shorting current proportional to the transport of polysulfides and b) cause a build-up of lithium- and sulfur-rich solid-electrolyte interphase (SEI) on the anode which irreversibly passivates the lithium metal anode. This effect must be supressed at all costs in conventional lithium-sulfur batteries, and is achieved by encouraging rapid precipitation of Li2S salts by the use of low-donor number solvents for the electrolyte such as diglyme (DME) and dioxolane (DOL). However, polysulfide chains (Li2Sx, 3 ≤ x ≤ 8) have great potential as redox couples due to their stable, successive multistep redox behaviour and have been successfully demonstrated in hybrid redox-flow battery configurations[2], in particular enabled by lithium nitrate as an additive to the catholyte that forms a stable SEI on the lithium metal surface that greatly reduces the polysulfide deposition. The lithium-polysulfide redox flow battery in theory far outstrips current state of the art vanadium redox flow batteries due to the higher capacity density in the catholyte (50-150 Wh/L vs 30 Wh/L), and the energy dense lithium metal[2]. However, the solubility of polysulfides decrease with chain length and depth of discharge, and high polarity, high donor number solvents that can enable high polysulfide concentrations[3] are typically far more reactive towards lithium metal[4]. Moreover lithium nitrate have little effect as anode protectant in this class of solvents compared to low donor number, low polarity solvents such as DME and DOL, and the polysulfide reduction pathway is dependent on the stabilising property of the solvent[5]. In collaboration with our commercial partner StorTera under the Faraday Institute, we have developed novel techniques for catholyte analysis. We show the role of nitrate consumption rate on protection of the anode, and the relative corrosive rate of lithium in a high polarity, high donor number class solvent (DMSO) versus conventional low polarity, low donor number class solvent (DOL/DME). Further we explore avenues to protect metallic lithium in highly concentrated polysulfide catholyte that enables large-scale energy storage that surpasses lithium-ion and vanadium redox flow batteries for cost, safety, serviceability and environmental impact. Such factors will be key for commercial deployment, in particular suitable for developing countries where microgrids for remote communities rely on intermittent renewable power supply. Zhang, G., Zhang, Z. W., Peng, H. J., Huang, J. Q. & Zhang, Q. A Toolbox for Lithium–Sulfur Battery Research: Methods and Protocols. Small Methods 1, 1–32 (2017). Yang, Y., Zheng, G. & Cui, Y. A membrane-free lithium/polysulfide semi-liquid battery for large-scale energy storage. Energy Environ. Sci. 6, 1552–1558 (2013). Pan, H. et al. On the Way Toward Understanding Solution Chemistry of Lithium Polysulfides for High Energy Li-S Redox Flow Batteries. Adv. Energy Mater. 5, (2015). Gupta, A., Bhargav, A. & Manthiram, A. Highly Solvating Electrolytes for Lithium–Sulfur Batteries. Adv. Energy Mater. 9, 1–9 (2019). Lu, Y. C., He, Q. & Gasteiger, H. A. Probing the lithium-sulfur redox reactions: A rotating-ring disk electrode study. J. Phys. Chem. C 118, 5733–5741 (2014).

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Suzanowicz, Artur M., Youngjin Lee, Hao Lin, Otavio J. J. Marques, Carlo U. Segre, and Braja K. Mandal. "A New Graphitic Nitride and Reduced Graphene Oxide-Based Sulfur Cathode for High-Capacity Lithium-Sulfur Cells." Energies 15, no. 3 (January 19, 2022): 702. http://dx.doi.org/10.3390/en15030702.

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Lithium-sulfur (Li-S) batteries can provide at least three times higher energy density than lithium-ion (Li-Ion) batteries. However, Li-S batteries suffer from a phenomenon called the polysulfide shuttle (PSS) that prevents the commercialization of these batteries. The PSS has several undesirable effects, such as depletion of active materials from the cathode, deleterious reactions between the lithium anode and electrolyte soluble lithium polysulfides, resulting in unfavorable coulombic efficiency, and poor cycle life of the battery. In this study, a new sulfur cathode composed of graphitic nitride as the polysulfide absorbing material and reduced graphene oxide as the conductive carbon host has been synthesized to rectify the problems associated with the PSS effect. This composite cathode design effectively retains lithium polysulfide intermediates within the cathode structure. The S@RGO/GN cathode displayed excellent capacity retention compared to similar RGO-based sulfur cathodes published by other groups by delivering an initial specific capacity of 1415 mA h g−1 at 0.2 C. In addition, the long-term cycling stability was outstanding (capacity decay at the rate of only 0.2% per cycle after 150 cycles).

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Yang, Chongyin, Liumin Suo, Oleg Borodin, Fei Wang, Wei Sun, Tao Gao, Xiulin Fan, et al. "Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility." Proceedings of the National Academy of Sciences 114, no. 24 (May 31, 2017): 6197–202. http://dx.doi.org/10.1073/pnas.1703937114.

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Leveraging the most recent success in expanding the electrochemical stability window of aqueous electrolytes, in this work we create a unique Li-ion/sulfur chemistry of both high energy density and safety. We show that in the superconcentrated aqueous electrolyte, lithiation of sulfur experiences phase change from a high-order polysulfide to low-order polysulfides through solid–liquid two-phase reaction pathway, where the liquid polysulfide phase in the sulfide electrode is thermodynamically phase-separated from the superconcentrated aqueous electrolyte. The sulfur with solid–liquid two-phase exhibits a reversible capacity of 1,327 mAh/(g of S), along with fast reaction kinetics and negligible polysulfide dissolution. By coupling a sulfur anode with different Li-ion cathode materials, the aqueous Li-ion/sulfur full cell delivers record-high energy densities up to 200 Wh/(kg of total electrode mass) for >1,000 cycles at ∼100% coulombic efficiency. These performances already approach that of commercial lithium-ion batteries (LIBs) using a nonaqueous electrolyte, along with intrinsic safety not possessed by the latter. The excellent performance of this aqueous battery chemistry significantly promotes the practical possibility of aqueous LIBs in large-format applications.

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Yuan, Meng, Haodong Shi, Cong Dong, Shuanghao Zheng, Kai Wang, Shaoxu Wang, and Zhong-Shuai Wu. "2D Cu₂₋ _x Se@graphene multifunctional interlayer boosting polysulfide rapid conversion and uniform Li₂S nucleation for high performance Li–S batteries." 2D Materials 9, no. 2 (March 31, 2022): 025028. http://dx.doi.org/10.1088/2053-1583/ac5ec6.

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Abstract Some vital challenges are main obstacles for further development of lithium–sulfur (Li–S) batteries such as low capacity and poor cycle stability resulted from polysulfide shuttling behavior, the physical/chemical entrapment is regarded as an effective method to inhibit and catalyze polysulfides. Herein we design a cross-linked framework of reduced graphene oxide anchored with Cu2−x Se nanoparticles (Cu2−x Se@rGO) by building an electrolyte/Cu2−x Se/graphene triple-phase interface to be a high-efficiency electrocatalyst for Li–S batteries. Importantly, this three-dimensional conductive network possesses a large specific surface area with high ion transport capability, meanwhile providing strong physical constraint for efficient adsorption of soluble polysulfides. Further, this triple-phase catalytic interface provides strong chemical adsorption and abundant Cu2−x Se nanoparticle sulfiphilic active sites, effectively inhibiting the dissolution of polysulfides and guaranteeing the efficient polysulfide adsorption catalysis as well as rapidly uniform Li2S nucleation. Consequently, with the Cu2−x Se@rGO separator, a lower capacity decay rate about 0.059% per cycle after 500 cycles at 2 C is obtained. What’s more, with a higher areal sulfur loading of 3.0 mg cm−2, the capacity is still maintained at 805 mAh g−1 over 100 cycles. Therefore, this work will open new avenue to construct 2D transition metal selenide for superior performance Li–S batteries.

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35

Bełtowski, Jerzy, and Krzysztof Wiórkowski. "Role of Hydrogen Sulfide and Polysulfides in the Regulation of Lipolysis in the Adipose Tissue: Possible Implications for the Pathogenesis of Metabolic Syndrome." International Journal of Molecular Sciences 23, no. 3 (January 25, 2022): 1346. http://dx.doi.org/10.3390/ijms23031346.

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Hydrogen sulfide (H2S) and inorganic polysulfides are important signaling molecules; however, little is known about their role in the adipose tissue. We examined the effect of H2S and polysulfides on adipose tissue lipolysis. H2S and polysulfide production by mesenteric adipose tissue explants in rats was measured. The effect of Na2S and Na2S4, the H2S and polysulfide donors, respectively, on lipolysis markers, plasma non-esterified fatty acids (NEFA) and glycerol, was examined. Na2S but not Na2S4 increased plasma NEFA and glycerol in a time- and dose-dependent manner. Na2S increased cyclic AMP but not cyclic GMP concentration in the adipose tissue. The effect of Na2S on NEFA and glycerol was abolished by the specific inhibitor of protein kinase A, KT5720. The effect of Na2S on lipolysis was not abolished by propranolol, suggesting no involvement of β-adrenergic receptors. In addition, Na2S had no effect on phosphodiesterase activity in the adipose tissue. Obesity induced by feeding rats a highly palatable diet for 1 month was associated with increased plasma NEFA and glycerol concentrations, as well as greater H2S production in the adipose tissue. In conclusion, H2S stimulates lipolysis and may contribute to the enhanced lipolysis associated with obesity.

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Ikeda, Mayumi, Yu Ishima, Victor T. G. Chuang, Maki Sakai, Hiroki Osafune, Hidenori Ando, Taro Shimizu, et al. "Distribution of Polysulfide in Human Biological Fluids and Their Association with Amylase and Sperm Activities." Molecules 24, no. 9 (April 30, 2019): 1689. http://dx.doi.org/10.3390/molecules24091689.

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Intracellular polysulfide could regulate the redox balance via its anti-oxidant activity. However, the existence of polysulfide in biological fluids still remains unknown. Recently, we developed a quantitative analytical method for polysulfide and discovered that polysulfide exists in plasma and responds to oxidative stress. In this study, we confirmed the presence of polysulfide in other biological fluids, such as semen and nasal discharge. The levels of polysulfide in these biological fluids from healthy volunteers (n = 9) with identical characteristics were compared. Additionally, the circadian rhythm of plasma polysulfide was also investigated. The polysulfide levels detected from nasal discharge and seminal fluid were approximately 400 and 600 μM, respectively. No correlation could be found between plasma polysulfide and the polysulfide levels of tear, saliva, and nasal discharge. On the other hand, seminal polysulfide was positively correlated with plasma polysulfide, and almost all polysulfide contained in semen was found in seminal fluid. Intriguingly, saliva and seminal polysulfide strongly correlated with salivary amylase and sperm activities, respectively. These results provide a foundation for scientific breakthroughs in various research areas like infertility and the digestive system process.

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Seel, F., and M. Wagner. "Polysulfid-Radikalionen in Aceton / Polysulfide Radical Ions in Acetone." Zeitschrift für Naturforschung B 42, no. 6 (June 1, 1987): 801. http://dx.doi.org/10.1515/znb-1987-0630.

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Abstract The formation of sulfur radical ions S 3 ~ and S 4 " in the blue and violet solutions of potassium sulfide and sulfur in acetone on adding 18C6 crown ether has been demonstrated by spectrophotometric titra-tion under anaerobic conditions. Neither the colour nor the spectra of the solutions point at S 2 ~.

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Wajon, J. E., and A. Heitz. "The reactions of some sulfur compounds in water supplies in Perth, Australia." Water Science and Technology 31, no. 11 (June 1, 1995): 87–92. http://dx.doi.org/10.2166/wst.1995.0409.

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Some residents of Perth, Australia, receiving treated groundwater have complained of intermittent swampy, cooked vegetable odours in their drinking water. The compound primarily responsible is dimethyl trisulfide (CH3SSSCH3) which can be formed in the laboratory from the reaction of methyl iodide with thiosulfate (in the presence of iodine or sulfide) or with polysulfide (Sn2−). Addition of chlorine or sulfide to pre-formed S-methylthiosulfate (produced from the reaction of methyl iodide with sodium thiosulfate) at concentrations possibly expected in water supplies did not produce the swampy odour or only formed it slowly. Dimethyl trisulfide was formed upon the addition of methyl iodide to samples from each water supply system examined, even from those not prone to the formation of swampy odour, suggesting each contained polysulfide. Polysulfides and the reducing agents sodium oxalate, sodium borohydride and sodium thiosulfate reacted with dimethyl trisulfide in solution, removing 50-100% of that originally present.

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Liu, Ning, Lu Wang, Taizhe Tan, Yan Zhao, and Yongguang Zhang. "TiO2/GO-coated functional separator to suppress polysulfide migration in lithium–sulfur batteries." Beilstein Journal of Nanotechnology 10 (August 19, 2019): 1726–36. http://dx.doi.org/10.3762/bjnano.10.168.

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Lithium–sulfur batteries render a high energy density but suffer from poor cyclic performance due to the dissolution of intermediate polysulfides. Herein, a lightweight nanoporous TiO2 and graphene oxide (GO) composite is prepared and utilized as an interlayer between a Li anode and a sulfur cathode to suppress the polysulfide migration and improve the electrochemical performance of Li/S batteries. The interlayer can capture the polysulfides due to the presence of oxygen functional groups and formation of chemical bonds. The hierarchically porous TiO2 nanoparticles are tightly wrapped in GO sheets and facilitate the polysulfide storage and chemical absorption. The excellent adhesion between TiO2 nanoparticles and GO sheets resulted in enhanced conductivity, which is highly desirable for an efficient electron transfer process. The Li/S battery with a TiO2/GO-coated separator exhibited a high initial discharge capacity of 1102.8 mAh g−1 and a 100th cycle capacity of 843.4 mAh g−1, which corresponds to a capacity retention of 76.48% at a current rate of 0.2 C. Moreover, the Li/S battery with the TiO2/GO-coated separator showed superior cyclic performance and excellent rate capability, which shows the promise of the TiO2/GO composite in next-generation Li/S batteries.

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Roman, Pawel, Martijn F. M. Bijmans, and Albert J. H. Janssen. "Quantification of individual polysulfides in lab-scale and full-scale desulfurisation bioreactors." Environmental Chemistry 11, no. 6 (2014): 702. http://dx.doi.org/10.1071/en14128.

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Environmental context Emission into the atmosphere of gaseous streams containing sulfur compounds, such as H2S and SOx, will lead to the unwanted formation of acid rain. In order to prevent this, biological processes can be employed to treat sulfur-containing gas streams. In this study, we describe a way to investigate the speciation of polysulfide anions in biodesulfurisation systems, which might enable further understanding and development of these processes. Abstract Environmental pollution caused by the combustion of fuel sources containing inorganic and organic sulfur compounds such as hydrogen sulfide (H2S) and thiols, is a global issue as it leads to SO2 emissions. To remove H2S from gas streams such as liquefied petroleum gas (LPG), biological processes can be applied. In these processes, polysulfide anions (Sx2–) play a significant role as they enhance the dissolution of H2S and act as intermediates in the biological oxidation of hydrogen sulfide ions to elemental sulfur. Despite their important role, the distribution of the various polysulfide species in full-scale biodesulfurisation systems has not yet been reported. With conventionally applied spectrophotometric analysis it is only possible to determine the total concentration of Sx2–. Moreover, this method is very sensitive to matrix effects. In this paper, we apply a method that relies on the derivatisation of Sx2– to dimethyl polysulfanes. Owing to the instability of higher dimethyl polysulfanes (Me2S4 to Me2S8), standards are not commercially available and had to be prepared by us. We present a simplified quantification method for higher dimethyl polysulfanes by calculating high performance liquid chromatogaphy (HPLC) UV response factors based on the addition of internal standards. The method was subsequently used to assess the distribution of polysulfide anions in both a laboratory-scale and a full-scale biodesulfurisation unit. We found that the average chain length of polysulfides strongly depends on the process conditions and a maximum of 5.33 sulfur atoms per polysulfide molecule was measured. Results of this study are required by mechanistic and kinetic models that attempt to describe product selectivity of sulfide oxidising bioreactors.

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Thangavel, Ranjith, Aravindaraj G. Kannan, Rubha Ponraj, Karthikeyan Kaliyappan, Won-Sub Yoon, Dong-Won Kim, and Yun-Sung Lee. "Cinnamon-Derived Hierarchically Porous Carbon as an Effective Lithium Polysulfide Reservoir in Lithium–Sulfur Batteries." Nanomaterials 10, no. 6 (June 22, 2020): 1220. http://dx.doi.org/10.3390/nano10061220.

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Lithium–sulfur batteries are attractive candidates for next generation high energy applications, but more research works are needed to overcome their current challenges, namely: (a) the poor electronic conductivity of sulfur, and (b) the dissolution and migration of long-chain polysulfides. Inspired by eco-friendly and bio-derived materials, we synthesized highly porous carbon from cinnamon sticks. The bio-carbon had an ultra-high surface area and large pore volume, which serves the dual functions of making sulfur particles highly conductive and acting as a polysulfide reservoir. Sulfur was predominantly impregnated into pores of the carbon, and the inter-connected hierarchical pore structure facilitated a faster ionic transport. The strong carbon framework maintained structural integrity upon volume expansion, and the unoccupied pores served as polysulfide trapping sites, thereby retaining the polysulfide within the cathode and preventing sulfur loss. These mechanisms contributed to the superior performance of the lithium-sulfur cell, which delivered a discharge capacity of 1020 mAh g−1 at a 0.2C rate. Furthermore, the cell exhibited improved kinetics, with an excellent cycling stability for 150 cycles with a very low capacity decay of 0.10% per cycle. This strategy of combining all types of pores (micro, meso and macro) with a high pore volume and ultra-high surface area had a synergistic effect on improving the performance of the sulfur cathode.

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Capkova, Dominika, Tomas Kazda, Ondrej Petruš, Ján Macko, Kamil Jasso, A. Baskevich, Elena Shembel, and Andrea Strakova Fedorkova. "Pyrite as a Low-Cost Additive in Sulfur Cathode Material for Stable Cycle Performance." ECS Transactions 105, no. 1 (November 30, 2021): 191–98. http://dx.doi.org/10.1149/10501.0191ecst.

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Various materials have been reported as an efficient host for sulfur to suppress large volume variation and polysulfide shuttle in lithium-sulfur batteries. Carbon materials are widely used as a matrix for sulfur to improve cycle performance and confine sulfur. Addition of transition metal sulfides into cathode material can improve cycle stability due to high efficiency of chemisorption and suppressing the polysulfide diffusion. In this work, various additions of pyrite to carbon and sulfur in the cathode material were investigated. The results show that the amount of pyrite has an affect on capacity and cycle stability of the electrode. Consequently, the lithium-sulfur batteries with the composite cathodes, containing 10 % of pyrite, exhibits stable discharge capacity of 788 mAh g-1 after 60 cycles at 0.2 C. Pyrite is a promising electrocatalyst in advanced lithium-sulfur batteries in the merits of low-cost, eco-friendliness and high activity towards polysulfides conversion reaction.

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Zhang, Feng, Yuan Gao, Feichao Wu, Lin Li, Jingde Li, and Guirong Wang. "Constructing MIL-101(Cr) membranes on carbon nanotube films as ion-selective interlayers for lithium–sulfur batteries." Nanotechnology 33, no. 21 (February 28, 2022): 215401. http://dx.doi.org/10.1088/1361-6528/ac5443.

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Abstract It is of significant importance to suppress the polysulfide shuttle effect for the commercial application of lithium–sulfur batteries. Herein, continuous MIL-101(Cr) membranes were successfully fabricated on carbon nanotube films utilizing a simple in situ growth method, aiming at constructing interlayer materials for inhibiting the shuttle effect. Owing to the suitable pore aperture and super electrolyte wettability, the as-developed MIL-101(Cr) membrane can effectively inhibit the shuttle behaviour of polysulfides while allowing the fast transport of Li-ions simultaneously, working as an ionic sieve. Additionally, this MOFs membrane is also helpful in accelerating the polysulfide catalytic conversion. Therefore, the proposed interlayer delivers an extraordinary rate capability, showing a remarkable capacity of 661.9 mAh g−1 under 5 C. Meanwhile, it also exhibits a high initial capacity of 816.1 mAh g−1 at 1 C and an exceptional durability with an extremely low capacity fading of 0.046% per cycle over 500 cycles.

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Dürichen, Peter, and Wolfgang Bensch. "Reactions in Molten Alkalimetal Polychalcogenides: What Happens in the Melt? A Study of the Reactions in the System K-Nb-S Using Differential Scanning Calorimetry, Infrared Spectroscopy, and X-Ray Powder Diffraction." Zeitschrift für Naturforschung B 57, no. 12 (December 1, 2002): 1382–86. http://dx.doi.org/10.1515/znb-2002-1207.

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The reactions of potassium polysulfides with elemental Nb were investigated with different analytical techniques. The amount of the polysulfide applied has no influence onto product formation, i. e. the ratio K2Sx: Nb is not important. The length of the polsysulfide chain, i. e. the value of x in K2Sx determines what product is formed. In sulfur-poor melts, K3NbS4 is observed. Increasing x to 5 - 6, K4Nb2S11 is formed with a structure containing S22− anions. Finally, applying a melt with x > 6, K6Nb4S25 is found as the product with a crystal structure containing the S52− polysulfide anion. When K2Sx (x < 5) is heated with sulfur in the first step the pentasulfide K2S5 is formed. Immediately after melting of K2S5 a reaction with elemental Nb occurs. The results of FT-IR and X-ray investigations have demonstrated that after oxidation the anion [Nb2S11]4− is formed relatively fast, and after a short time crystalline K4Nb2S11 can be detected. After 24 h the reaction is complete.

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Kitadai, Norio, Satoshi Okada, Akiko Makabe, Eiji Tasumi, and Masayuki Miyazaki. "Polysulfide-assisted urea synthesis from carbon monoxide and ammonia in water." PeerJ Organic Chemistry 4 (July 11, 2022): e6. http://dx.doi.org/10.7717/peerj-ochem.6.

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Efficient conversion of carbon monoxide into urea in an aqueous ammonia solution was demonstrated through coupling with the elemental sulfur reduction to polysulfides. This reaction starts with a simple mixture of carbon monoxide, ammonia, elemental sulfur, and a small amount of hydrogen sulfide for polysulfide formation, enabling an almost complete conversion of 1 atm of carbon monoxide to urea (95–100% yield) within 216, 64, and 32 h at 35 °C, 50 °C, and 65 °C, respectively. Polysulfides control the overall reaction rate while suppressing the accumulation of a by-product, hydrogen sulfide, to less than 1 Pa. These functions follow simple kinetic and thermodynamic theories, enabling prediction-based reaction control. This operational merit, together with the superiority of water as a green solvent, suggests that our demonstrated urea synthesis is a promising option for sulfur utilization beneficial for agricultural production.

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DeLeon, Eric R., Yan Gao, Evelyn Huang, and Kenneth R. Olson. "Garlic oil polysulfides: H2S- and O2-independent prooxidants in buffer and antioxidants in cells." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 310, no. 11 (June 1, 2016): R1212—R1225. http://dx.doi.org/10.1152/ajpregu.00061.2016.

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The health benefits of garlic and other organosulfur-containing foods are well recognized and have been attributed to both prooxidant and antioxidant activities. The effects of garlic are surprisingly similar to those of hydrogen sulfide (H2S), which is also known to be released from garlic under certain conditions. However, recent evidence suggests that polysulfides, not H2S, may be the actual mediator of physiological signaling. In this study, we monitored formation of H2S and polysulfides from garlic oil in buffer and in human embryonic kidney (HEK) 293 cells with fluorescent dyes, 7-azido-4-methylcoumarin and SSP4, respectively and redox activity with two redox indicators redox-sensitive green fluorescent protein (roGFP) and DCF. Our results show that H2S release from garlic oil in buffer requires other low-molecular-weight thiols, such as cysteine (Cys) or glutathione (GSH), whereas polysulfides are readily detected in garlic oil alone. Administration of garlic oil to cells rapidly increases intracellular polysulfide but has minimal effects on H2S unless Cys or GSH are also present in the extracellular medium. We also observed that garlic oil and diallyltrisulfide (DATS) potently oxidized roGFP in buffer but did not affect DCF. This appears to be a direct polysulfide-mediated oxidation that does not require a reactive oxygen species intermediate. Conversely, when applied to cells, garlic oil became a significant intracellular reductant independent of extracellular Cys or GSH. This suggests that intracellular metabolism and further processing of the sulfur moieties are necessary to confer antioxidant properties to garlic oil in vivo.

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Heitz, A., R. I. Kagi, and R. Alexander. "Polysulfide sulfur in pipewall biofilms: its role in the formation of swampy odour in distribution systems." Water Science and Technology 41, no. 4-5 (February 1, 2000): 271–78. http://dx.doi.org/10.2166/wst.2000.0455.

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Biofilms and pipewall sediments in drinking water distribution systems were analysed for dimethylpolysulfides (DMPS) and inorganic polysulfides in an effort to determine the origin of dimethyltrisulfide, which causes unpleasant swampy odours in drinking water. Inorganic polysulfides were determined using the technique of methyl iodide derivatisation, and subsequent analysis as DMPS by gas chromatography-mass spectrometry. The technique was shown to be quantitative from 0.15 μg/L to 370 μg/L, and not subject to interference from other sulfur compounds. The polysulfide-rich biofilms and sediments occurred in pipes constructed from a variety of different materials, and fed by water from several different surface and groundwater sources. The biofilm/sediment matrix appeared to retard oxidation of polysulfides, by preventing their diffusion into the oxic water and by providing a barrier against the oxidative action of chlorine and dissolved oxygen.

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YOON, SUNG-HOON, HARRY CULLINAN, and GOPAL A. KRISHNAGOPALAN. "Polysulfide-borohydride modification of southern pine alkaline pulping integrated with hydrothermal pre-extraction of hemicelluloses." July 2011 10, no. 7 (August 1, 2011): 9–16. http://dx.doi.org/10.32964/tj10.7.9.

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We studied three process modifications to investigate their effects on the property and yield recovery capabilities of kraft pulping integrated with hemicellulose pre-extraction of southern pine. Loblolly pine chips were pre-extracted with hot water until the sugar extraction yield reached the targeted value of 10% and then subjected to conventional and modified kraft pulping. Modification included polysulfide pretreatment; polysulfide-sodium borohydride dual pretreatment, and polysulfide followed by polysulfide-sodium borohydride dual pretreatment two-stage pretreatments prior to kraft pulping. In the first modification, about 5% of the lost pulp yield (total 7%) caused by hemicellulose pre-extraction could be recovered with 15%-20% polysulfide pretreatment. Complete recovery (7%) was achieved with simultaneous pretreatment using 15% polysulfide and 0.5% sodium borohydride with 0.1% anthraquinone in polysulfide-sodium borohydride dual pretreatment. Two-stage pretreatment using recycled 15% polysulfide followed by simultaneous treatment of 6% polysulfide and 0.4%–0.5% sodium borohydride with 0.1% anthraquinone also achieved 100% yield recovery. Continuous recycling of 15% polysulfide employed in the two-stage process modification maintained its yield protection efficiency in a repeated recycling cycle. No significant changes in paper strength were found in handsheets prepared from the three process modifications, except for a minor reduction in tear strength.

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Yu, Xingwen, Tam Tran, Yudong Wang, Yanhua Sun, and Xiao-Dong Zhou. "Lithiation of an Agarose-Based Biopolymer Electrolyte for Li-S Batteries." ECS Meeting Abstracts MA2022-02, no. 4 (October 9, 2022): 398. http://dx.doi.org/10.1149/ma2022-024398mtgabs.

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Driven by the continually accelerating demand for energy storage, the development of batteries with high energy, high power, low cost, and high safety is an endless goal and eternally inspires researchers to pursue advanced energy storage technologies. Battery systems based on non-aqueous chemistry of lithium and sulfur have garnered overwhelming attention in the past decade. So far, many significant progresses have been made through rigorous research over the past decade. However, this battery technology still confronts considerably critical challenges. Due to their unique charge-discharge mechanism, electrochemical processes of a Li–S cell experience the formation of a sequence of soluble intermediate products existing in a variety form of polysulfides dissolved in the non-aqueous liquid electrolyte. Under the operating conditions of a Li-S cell, the solvated polysulfide species have a tendency to migrate from the positive electrode through the conventional porous separator to react with Li-metal anode. The shuttle of polysulfide can severely degrade the cell performance, lowers the cycling efficiency, and induces capacity fade during cycling. On the other hand, use of a lithium-metal anode in Li-S batteries would unavoidably lead to the additional persistent problem of Li dendrite with can easily penetrate a conventional porous separator and short the cell. These two problems — the polysulfide shuttle and lithium dendrites — are the most critical challenges for Li–S battery development. To overcome the above two issues, we present here a lithiated polymer membrane (as pictured in Figure 1a) which is developed from agarose (AG, with a unit molecular structure as displayed in Figure 1b) as a cation-selective electrolyte for Li–S batteries to suppress the polysulfide diffusion and to reduce the formation Li dendrite. Preliminary results of a Li ǁ AG ǁ Li symmetric cell showed that the membrane could sustain high-current-density operation with low overpotential (Figure 1c). The AG membrane exhibited amorphous structure (Figure 1d) and nonporous feature (Figure 1e). Our ongoing work includes the evaluation of dendrite-suppression capability and polysulfide-shuttle-inhibition function of the AG-based membrane, as well as the electrochemical performance of Li-S batteries with the AG membrane. In addition, ionic transport mechanism in the AG-based membrane will be presented as well. Figure 1

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Azam, Sakibul, Zhen Wei, and Ruigang Wang. "Nickel Cobalt Oxide Decorated Cerium Oxide Nanorods for Polysulfide Trapping and Catalytic Conversion in Advanced Lithium Sulfur Batteries." ECS Meeting Abstracts MA2022-02, no. 4 (October 9, 2022): 539. http://dx.doi.org/10.1149/ma2022-024539mtgabs.

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Lithium sulfur batteries (LSBs) are promising candidates for next-generation rechargeable batteries due to the active material sulfur being earth abundant, low cost and environmentally friendly element. But the most important feature of LSBs is that the theoretical capacity of sulfur is ~1645 mAh g-1 which is ~5 times higher than the conventional lithium-ion batteries. However, even with these valuable assets, LSB has not yet been commercialized due to the inherent problems of fast capacity loss resulting in low cycle lifetime. This capacity loss originates from the migration of dissolved sulfur discharge products in the electrolyte known as the notorious polysulfide shuttling effect. To deal with this issue, several research efforts have been made to trap the high order lithium polysulfides by a) physically encapsulation using high surface area carbonaceous materials and b) chemically binding the lithium polysulfides in its cathode host. Several materials are very popular to efficiently bind the lithium polysulfides such as transition metal oxides, nitrides, sulfides and have helped making significant advances to long cycle life lithium sulfur batteries. However, to make the transition to design next generation LSBs, there is a need for materials that can facilitate fast polysulfide conversion by catalytic reaction that will reduce the diffusion and agglomeration of polysulfides in the liquid organic electrolyte, resulting in high capacity and long cycle lifetime. With this strategy in mind, we have designed NiCoOx decorated on CeO2 nanorods support as cathode host material for LSBs to provide dual adsorption-catalysis synergy. The CeO2 nanorods with enriched surface defects can effectively bind the lithium polysulfides whereas the NiCoOx nanoclusters can provide highly efficient electrocatalytic sites to improve the conversion kinetics of elemental sulfur to high order lithium polysulfides to finally the lower order polysulfides. As a result, the derived LSBs exhibited excellent electrochemical performance with high capacity of 1236 mAh g-1 at 0.2C with a sulfur loading of 1.33 mg cm-2. Even with high sulfur loading 2.66 mg cm-2 the LSBs exhibits 755 mAh g-1 at 0.2C with a capacity decay of only 0.08% per cycle after 170 cycles. The battery also operates at the sulfur loading of 4 mg cm-2 and 5.33 mg cm-2 for more than 100 which is convincing considering commercialization of LSB. Key words: lithium sulfur batteries, lithium polysulfides, shuttle effect, cerium oxide, catalysis.

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Journal articles on the topic 'Polysulfide'

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