Organosulfides offer new opportunities for high performance lithium-sulfur(Li-S)batteries because of materials abundance,versatile structures and unique properties.Yet,their redox kinetics as well as cycling performan...Organosulfides offer new opportunities for high performance lithium-sulfur(Li-S)batteries because of materials abundance,versatile structures and unique properties.Yet,their redox kinetics as well as cycling performance need to be further improved.Employing redox mediators is a highly effective strategy to address above challenges.However,the underlying mechanism in this chemistry is so far insufficiently explored.Here,phenyl disulfide(Ph S–SPh)and phenyl diselenide(Ph Se–Se Ph)are used as a model system for mechanistic understanding of organosulfide electrochemistry,particularly the rate acceleration.Profiling the reaction thermodynamics and charge-discharge process reveals redox of both S–S and C–S bonds,as well as that the coupling between radical exchange and electrochemical redox is the key to enhance the sulfur kinetics.This study not only establishes a basic understanding of orgaonsulfide electrochemistry in Li-S batteries,but also points out a general strategy for enhancing the kinetics of sulfur electrodes in electrochemical devices.展开更多
A mercury（Ⅱ） iodide complex with organosulfide [Hg（pymt）（pymtH）I] 1 （pymt = the anion of pyrimidine-2-thiolate） has been synthesized by slow evaporation of the solution at room temperature and structurally ch...A mercury（Ⅱ） iodide complex with organosulfide [Hg（pymt）（pymtH）I] 1 （pymt = the anion of pyrimidine-2-thiolate） has been synthesized by slow evaporation of the solution at room temperature and structurally characterized by single-crystal X-ray diffraction. Basic ideas and data collected are given. X-ray diffraction analysis reveals that complex 1 is mononuclear. Crystallographic data： C8H7HgIN4S2, Mr = 550.79, monoclinic system, space group P21/c, a = 11.218（4）, b = 9.551（3）, c = 15.877（4） A^°, β = 129.697（15）°, V = 1308.9（7） A^°^3, Z = 4, Mr = 550.79, Dc = 2.795 g/cm^3, F（000） = 995, μ（MoKa） = 14.415 mm^-1, 2（MoKa） = 0.71073 A^°, T= 293（2） K, 2θmax = 54.9°, GOOF= 1.053, the final R = 0.0310 and wR = 0.0742 for 2547 observed reflections with I 〉 2σ（I） （refinement on F^2）. Complex 1 is connected through hydrogen bonds to give a one-dimensional supramolecular chain structure. Furthermore, π-π interactions are also found between the pyrimidine rings with the center-to-center distances of 3.439（4） and 3.603（4） A^°, so complex 1 expands the chains into a two-dimensional network.展开更多
Click chemistry is a rapid,reliable,and powerful function and a highly selective organic reaction that facilitates the efficient synthesis of various molecules by joining small units.This approach has found widespread...Click chemistry is a rapid,reliable,and powerful function and a highly selective organic reaction that facilitates the efficient synthesis of various molecules by joining small units.This approach has found widespread applications in fields such as drug development,chemical synthesis,and molecular biology.In recent years,the reaction of alkali-catalyzed polymerization of thiol and sulfur has been employed to prepare various sulfur-containing polymers,which are applied as electrochemical active electrode materials in the pursuit of good performance.In this study,it is surprising to find that the reaction mechanism exhibits characteristics of both the alkali-catalyzed sulfhydryl Micheal addition reaction and thiol-epoxy click chemistry;for the first time,thiol-sulfur click chemistry is defined in detail,providing a comprehensive description of its underlying scientific principles.The introduction of this new reaction pathway holds significant potential for advancing research and the development of sulfur-containing polymers.Based on this novel click chemistry,a new sulfur-containing polymer,polydivinylthioether hexasulfide,has been designed and successfully applied as a cathode material in lithium-organosulfide batteries.This material demonstrates excellent electrochemical performance,achieving an initial capacity that reaches 790.5 mAh g−1(82.6%of theoretical capacity),and in a long-term cycle test,the capacity decay rate is only 0.063%after 1,000 cycles.展开更多
Organic cathode materials exhibit higher energy storage capacity,their poor cyclability due to dissolution in liquid organic electrolytes remains a challenge.However,recently,the electrochemical behavior of organopoly...Organic cathode materials exhibit higher energy storage capacity,their poor cyclability due to dissolution in liquid organic electrolytes remains a challenge.However,recently,the electrochemical behavior of organopolysulfides incorporating N-heterocycles unveils promising cathode materials with stable cycling performance.Herein,the integration of organosulfides salt as cathodes with solid electrolytes,exemplified by sodium allyl(methyl)carbamodithioate and sodium diethylcarbamodithioate with a polymer solid electrolyte of polyethylene oxide and LiTFSI,addresses the poor electrochemical stability of organic electrodes.Comparative analysis highlights sodium allyl(methyl)carbamodithioate's superior electrochemical performance and stability compared with sodium diethylcarbamodithioate,emphasizing the efficacy of periphery aliphatic modification in enhancing electrode capacity,rate performance,and electrochemical stability for organosulfide materials within all-solid-state lithium organic batteries.We also explore the origin of periphery aliphatic modification in these enhancing electrochemical performances by kinetic analysis and thermodynamic analysis.Furthermore,employing density functional theory calculations and ex situ FTIR experiments elucidates the critical role of the N-C=S structure in the energy storage mechanism.This research advances organic cathode design within organosulfide materials,unlocking the potential of allsolid-state lithium organic batteries with enhanced cyclability,propelling the development of next-generation energy storage systems.展开更多
Lithium–sulfur(Li–S)battery as a high-energy density electrochemical energy storage system has attracted many researchers’attention.However,the shuttle effect of Li–S batteries and the challenges associated with l...Lithium–sulfur(Li–S)battery as a high-energy density electrochemical energy storage system has attracted many researchers’attention.However,the shuttle effect of Li–S batteries and the challenges associated with lithium metal anode caused poor cycle performance.In this work,the organosulfide poly(sulfur-1,3-diisopropenylbenzene)(PSD)was prepared as cathode material and additive of P(VDFHFP)polymer electrolyte(P(VDF-HFP)).It was verified that P(VDF-HFP)polymer electrolyte with 10%PSD(P(VDF-HFP)-10%PSD)showed a higher ionic conductivities than that of liquid electrolyte up to2.27×10-3 S cm-1 at room temperature.The quasi-solid-state Li-S batteries fabricated with organosulfide cathode material PSD and P(VDF-HFP)based functional polymer electrolyte delivered good cycling stability(780 m Ah g-1 after 200 th cycle at 0.1 C)and rate performance(613 m Ah g-1 at 1 C).The good cycling performance could be attributed to the synergistic effect of components,including the interaction between polysulfides and polymer main chain in the organosulfide cathode,the sustained organic/inorganic hybrid stable SEI layer formed by polymer electrolyte additive PSD,the improved cathode/electrolyte interface and the good affinity between P(VDF-HFP)based functional polymer electrolyte and Li metal surface.This strategy herein may provide a new route to fabricate high-performance Li–S batteries through the organosulfide cathode and functional polymer electrolyte.展开更多
Rechargeable lithium-sulfur(Li-S)batteries are considered one of the most promising energy storage techniques owing to the high theoretical energy density.However,challenges still remain such as the shuttle effect of ...Rechargeable lithium-sulfur(Li-S)batteries are considered one of the most promising energy storage techniques owing to the high theoretical energy density.However,challenges still remain such as the shuttle effect of lithium polysulfides(LPSs)and the instability of lithium metal anode.Herein,we propose to use nitrogen-rich azoles,i.e.,triazole(Ta)and tetrazole(Tta),as trifunctional electrolyte additives for Li-S batteries.The azoles afford strong lithiophilicity for the chemisorption of LPSs.The density functional theory and experimental analysis verify the presence of Li bonds between the azoles and LPSs.The azoles can also interact with lithium salt in the electrolyte,leading to increase ionic conductivity and lithiumion transference number.Moreover,the azoles render particle-like lithium deposition on the lithium metal anode,leading to superlong cycling of a Li symmetric cell.The Li-S batteries with Ta and Tta exhibit the initial discharge capacity of 1425.5 and 1322.2 m Ah g^(-1),respectively,at 0.2 C rate,and promising cycling stability.They also enable enhanced cycling performance of a Li-organosulfide battery.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.21975087,51821005,U1966214)the Certificate of China Postdoctoral Science Foundation(Grant Nos.2020 M672337,2019 M652634)。
文摘Organosulfides offer new opportunities for high performance lithium-sulfur(Li-S)batteries because of materials abundance,versatile structures and unique properties.Yet,their redox kinetics as well as cycling performance need to be further improved.Employing redox mediators is a highly effective strategy to address above challenges.However,the underlying mechanism in this chemistry is so far insufficiently explored.Here,phenyl disulfide(Ph S–SPh)and phenyl diselenide(Ph Se–Se Ph)are used as a model system for mechanistic understanding of organosulfide electrochemistry,particularly the rate acceleration.Profiling the reaction thermodynamics and charge-discharge process reveals redox of both S–S and C–S bonds,as well as that the coupling between radical exchange and electrochemical redox is the key to enhance the sulfur kinetics.This study not only establishes a basic understanding of orgaonsulfide electrochemistry in Li-S batteries,but also points out a general strategy for enhancing the kinetics of sulfur electrodes in electrochemical devices.
基金supported by 973 Program (2006CB932900)the National Natural Science Foundation of China (20571074)
文摘A mercury（Ⅱ） iodide complex with organosulfide [Hg（pymt）（pymtH）I] 1 （pymt = the anion of pyrimidine-2-thiolate） has been synthesized by slow evaporation of the solution at room temperature and structurally characterized by single-crystal X-ray diffraction. Basic ideas and data collected are given. X-ray diffraction analysis reveals that complex 1 is mononuclear. Crystallographic data： C8H7HgIN4S2, Mr = 550.79, monoclinic system, space group P21/c, a = 11.218（4）, b = 9.551（3）, c = 15.877（4） A^°, β = 129.697（15）°, V = 1308.9（7） A^°^3, Z = 4, Mr = 550.79, Dc = 2.795 g/cm^3, F（000） = 995, μ（MoKa） = 14.415 mm^-1, 2（MoKa） = 0.71073 A^°, T= 293（2） K, 2θmax = 54.9°, GOOF= 1.053, the final R = 0.0310 and wR = 0.0742 for 2547 observed reflections with I 〉 2σ（I） （refinement on F^2）. Complex 1 is connected through hydrogen bonds to give a one-dimensional supramolecular chain structure. Furthermore, π-π interactions are also found between the pyrimidine rings with the center-to-center distances of 3.439（4） and 3.603（4） A^°, so complex 1 expands the chains into a two-dimensional network.
基金supported by the National Natural Science Foundation of China(52463013 and 52073133)the Major Science and Technology Project of Gansu Province(22ZD6GA008)the Incubation Program of Excelent Doctoral Dissertation-Lanzhou Univer-sity of Technology.
文摘Click chemistry is a rapid,reliable,and powerful function and a highly selective organic reaction that facilitates the efficient synthesis of various molecules by joining small units.This approach has found widespread applications in fields such as drug development,chemical synthesis,and molecular biology.In recent years,the reaction of alkali-catalyzed polymerization of thiol and sulfur has been employed to prepare various sulfur-containing polymers,which are applied as electrochemical active electrode materials in the pursuit of good performance.In this study,it is surprising to find that the reaction mechanism exhibits characteristics of both the alkali-catalyzed sulfhydryl Micheal addition reaction and thiol-epoxy click chemistry;for the first time,thiol-sulfur click chemistry is defined in detail,providing a comprehensive description of its underlying scientific principles.The introduction of this new reaction pathway holds significant potential for advancing research and the development of sulfur-containing polymers.Based on this novel click chemistry,a new sulfur-containing polymer,polydivinylthioether hexasulfide,has been designed and successfully applied as a cathode material in lithium-organosulfide batteries.This material demonstrates excellent electrochemical performance,achieving an initial capacity that reaches 790.5 mAh g−1(82.6%of theoretical capacity),and in a long-term cycle test,the capacity decay rate is only 0.063%after 1,000 cycles.
基金supported by the National Natural Science Foundation of China(52272088,52072273 and 51972239)the Zhejiang Provincial Natural Science Foundation of China(LZ21E020001)the Key Lab of Advanced Energy Storage and Conversion(2021HZSY0051)。
文摘Organic cathode materials exhibit higher energy storage capacity,their poor cyclability due to dissolution in liquid organic electrolytes remains a challenge.However,recently,the electrochemical behavior of organopolysulfides incorporating N-heterocycles unveils promising cathode materials with stable cycling performance.Herein,the integration of organosulfides salt as cathodes with solid electrolytes,exemplified by sodium allyl(methyl)carbamodithioate and sodium diethylcarbamodithioate with a polymer solid electrolyte of polyethylene oxide and LiTFSI,addresses the poor electrochemical stability of organic electrodes.Comparative analysis highlights sodium allyl(methyl)carbamodithioate's superior electrochemical performance and stability compared with sodium diethylcarbamodithioate,emphasizing the efficacy of periphery aliphatic modification in enhancing electrode capacity,rate performance,and electrochemical stability for organosulfide materials within all-solid-state lithium organic batteries.We also explore the origin of periphery aliphatic modification in these enhancing electrochemical performances by kinetic analysis and thermodynamic analysis.Furthermore,employing density functional theory calculations and ex situ FTIR experiments elucidates the critical role of the N-C=S structure in the energy storage mechanism.This research advances organic cathode design within organosulfide materials,unlocking the potential of allsolid-state lithium organic batteries with enhanced cyclability,propelling the development of next-generation energy storage systems.
基金Financial supports from the National Natural Science Foundation of China(51532002 and 51872027)Beijing Natural Science Foundation(L172023)National Basic Research Program of China(2016YFA0202500,2017YFE0113500,and 2018YFB0104300)。
文摘Lithium–sulfur(Li–S)battery as a high-energy density electrochemical energy storage system has attracted many researchers’attention.However,the shuttle effect of Li–S batteries and the challenges associated with lithium metal anode caused poor cycle performance.In this work,the organosulfide poly(sulfur-1,3-diisopropenylbenzene)(PSD)was prepared as cathode material and additive of P(VDFHFP)polymer electrolyte(P(VDF-HFP)).It was verified that P(VDF-HFP)polymer electrolyte with 10%PSD(P(VDF-HFP)-10%PSD)showed a higher ionic conductivities than that of liquid electrolyte up to2.27×10-3 S cm-1 at room temperature.The quasi-solid-state Li-S batteries fabricated with organosulfide cathode material PSD and P(VDF-HFP)based functional polymer electrolyte delivered good cycling stability(780 m Ah g-1 after 200 th cycle at 0.1 C)and rate performance(613 m Ah g-1 at 1 C).The good cycling performance could be attributed to the synergistic effect of components,including the interaction between polysulfides and polymer main chain in the organosulfide cathode,the sustained organic/inorganic hybrid stable SEI layer formed by polymer electrolyte additive PSD,the improved cathode/electrolyte interface and the good affinity between P(VDF-HFP)based functional polymer electrolyte and Li metal surface.This strategy herein may provide a new route to fabricate high-performance Li–S batteries through the organosulfide cathode and functional polymer electrolyte.
基金supported by the National Natural Science Foundation of China(Grant Nos.U2004214,21975225,and 51902293)。
文摘Rechargeable lithium-sulfur(Li-S)batteries are considered one of the most promising energy storage techniques owing to the high theoretical energy density.However,challenges still remain such as the shuttle effect of lithium polysulfides(LPSs)and the instability of lithium metal anode.Herein,we propose to use nitrogen-rich azoles,i.e.,triazole(Ta)and tetrazole(Tta),as trifunctional electrolyte additives for Li-S batteries.The azoles afford strong lithiophilicity for the chemisorption of LPSs.The density functional theory and experimental analysis verify the presence of Li bonds between the azoles and LPSs.The azoles can also interact with lithium salt in the electrolyte,leading to increase ionic conductivity and lithiumion transference number.Moreover,the azoles render particle-like lithium deposition on the lithium metal anode,leading to superlong cycling of a Li symmetric cell.The Li-S batteries with Ta and Tta exhibit the initial discharge capacity of 1425.5 and 1322.2 m Ah g^(-1),respectively,at 0.2 C rate,and promising cycling stability.They also enable enhanced cycling performance of a Li-organosulfide battery.
