Lithium dendrite growth due to uneven electrodeposition usually leads to the potential hazard of internal short circuit and shorter lifetime of lithium-based batteries. Extensive efforts have been devoted to explore t...Lithium dendrite growth due to uneven electrodeposition usually leads to the potential hazard of internal short circuit and shorter lifetime of lithium-based batteries. Extensive efforts have been devoted to explore the effects of single or two factors on dendrite growth, involving the diffusion coefficient, exchange current density, electrolyte concentration, temperature, and applied voltage. However, these factors interrelate during battery operation, signifying that a understanding of how they jointly influence the electrodeposition is of paramount importance for the effective suppression of dendrites. Here, we incorporate the dependent relationships among key factors into the phase-field model to capture their synergistic effects on electrodeposition. All the simulations are implemented in our self-written MATLAB code under a unified modeling framework. Following this, five groups of experimentally common dendrite patterns are reproduced and the corresponding electrodeposition driving forces are identified. Unexpectedly, we find that with the decrease of the ratio of exchange current density(or applied voltage) to diffusion coefficient, the electrodeposition morphology changes from needle-like dendrites to columnar dendrites and to uniform deposition. The present phase-field simulation tends to depict the practical electrodeposition process, providing important insights into synergistic regulation to suppress dendrite growth.展开更多
Graphite nanosheets with the average thicknesses ranging from 24.4 to 48.9 nm were prepared with the use of expanded graphite as the raw material by sand milling in deionized water,anhydrous ethanol,glycerol,and 1,4-b...Graphite nanosheets with the average thicknesses ranging from 24.4 to 48.9 nm were prepared with the use of expanded graphite as the raw material by sand milling in deionized water,anhydrous ethanol,glycerol,and 1,4-butanediol,respectively.Anhydrous ethanol favored the formation of graphite nanosheets with a smaller average thickness.When the graphite nanosheets with the content of 2 wt%were added in lithium-based grease,the average friction coefficient decreased by 27%as compared with the pure lithium-based grease.The weld point and load wear index were 1.6 and 1.4 times those of the pure lithium-based grease,respectively.The tribological properties of the graphite nanosheet-containing lithium-based grease were comparable with those of the graphene-containing lithium-based grease.展开更多
Sulfide solid electrolytes are widely regarded as one of the most promising technical routes to realize all-solid-state batteries(ASSBs)due to their high ionic conductivity and favorable deformability.However,the rela...Sulfide solid electrolytes are widely regarded as one of the most promising technical routes to realize all-solid-state batteries(ASSBs)due to their high ionic conductivity and favorable deformability.However,the relatively high price of the crucial starting material,Li_(2)S,results in high costs of sulfide solid electrolytes,limiting their practical application in ASSBs.To solve this problem,we develop a new synthesis route of Li_(2)S via liquid-phase synthesis method,employing lithium and biphenyl in 1,2-dimethoxyethane(DME)ether solvent to form a lithium solution as the lithium precursor.Because of the comparatively strong reducibility of the lithium solution,its reaction with sulfur proceeds effectively even at room temperature.This new synthesis route of Li_(2)S starts with cheap precursors of lithium,sulfur,biphenyl and DME solvent,and the only remaining byproduct(DME solution of biphenyl)after the collection of Li_(2)S product can be recycled and reused.Besides,the reaction can proceed effectively at room temperature with mild condition,reducing energy cost to a great extent.The as-synthesized Li_(2)S owns uniform and extremely small particle size,proved to be feasible in synthesizing sulfide solid electrolytes(such as the solid-state synthesis of Li_(6)PS_(5)C_(l)).Spontaneously,this lithium solution can be directly employed in the synthesis of Li_(3)PS_(4) solid electrolytes via liquid-phase synthesis method,in which the centrifugation and heat treatment processes of Li_(2)S are not necessary,providing simplified production process.The as-synthesized Li_(3)PS_(4) exhibits typical Li+conductivity of 1.85×10^(-4) S·cm^(-1) at 30℃.展开更多
The rapid evolution of lithium-ion batteries over the past decade,coupled with their extensive commercial utilization,has entrenched lithium-ion technology as a cornerstone in the energy-storage field.Despite this est...The rapid evolution of lithium-ion batteries over the past decade,coupled with their extensive commercial utilization,has entrenched lithium-ion technology as a cornerstone in the energy-storage field.Despite this established position,the prevalence of liquid electrolytes in contemporary batteries has been beset by inherent vulnerabilities,including susceptibility to leakage,volatility,and combustibility.In response,polymer electrolytes have emerged as a promising alternative,distinguished by their superior safety profile,elevated energy density,and prolonged operational lifespan.Nevertheless,the widespread adoption of polymer electrolytes also has impediments such as constrained mobility and the propensity for forming lithium dendrite.Addressing these issues is paramount for the further advancement of polymer electrolyte technology.This review aims to provide a comprehensive elucidation of gel polymer electrolytes,solid polymer electrolytes,and composite polymer electrolytes,the predominant subclasses within the field of polymer electrolytes.A systematic exposition of diverse polymer electrolyte formulations,encompassing their respective merits and demerits alongside prospective applications,will be undertaken.Particular emphasis will be put on the strategies applied to ameliorate battery performance to delineate the avenues for potential enhancement in this critical domain.展开更多
Lithium-based batteries have had a profound impact on modern society through their extensive use in portable electronic devices,electric vehicles,and energy storage systems.However,battery safety issues such as therma...Lithium-based batteries have had a profound impact on modern society through their extensive use in portable electronic devices,electric vehicles,and energy storage systems.However,battery safety issues such as thermal runaway,fire,and explosion hinder their practical application,especially for using metal anode.These problems are closely related to the high flammability of conventional electrolytes and have prompted the study of flameretardant and nonflammable electrolytes.Here,we review the recent research on nonflammable electrolytes used in lithium-based batteries,including phosphates,fluorides,fluorinated phosphazenes,ionic liquids,deep eutectic solvents,aqueous electrolytes,and solid-state electrolytes.Their flame-retardant mechanisms and efficiency are discussed,as well as their influence on cell electrochemical performance.We conclude with a summary of future prospects for the design of nonflammable electrolytes and the construction of safer lithium-based batteries.展开更多
The application of lithium-based batteries is challenged by the safety issues of leakage and flammability of liquid electrolytes.Polymer electrolytes(PEs)can address issues to promote the practical use of lithium meta...The application of lithium-based batteries is challenged by the safety issues of leakage and flammability of liquid electrolytes.Polymer electrolytes(PEs)can address issues to promote the practical use of lithium metal batteries.However,the traditional preparation of PEs such as the solution-casting method requires a complicated preparation process,especially resulting in side solvents evaporation issues.The large thickness of traditional PEs reduces the energy density of the battery and increases the transport bottlenecks of lithium-ion.Meanwhile,it is difficult to fill the voids of electrodes to achieve good contact between electrolyte and electrode.In situ polymerization appears as a facile method to prepare PEs possessing excellent interfacial compatibility with electrodes.Thus,thin and uniform electrolytes can be obtained.The interfacial impedance can be reduced,and the lithium-ion transport throughput at the interface can be increased.The typical in situ polymerization process is to implant a precursor solution containing monomers into the cell and then in situ solidify the precursor under specific initiating conditions,and has been widely applied for the preparation of PEs and battery assembly.In this review,we focus on the preparation and application of in situ polymerization method in gel polymer electrolytes,solid polymer electrolytes,and composite polymer electrolytes,in which different kinds of monomers and reactions for in situ polymerization are discussed.In addition,the various compositions and structures of inorganic fillers,and their effects on the electrochemical properties are summarized.Finally,challenges and perspectives for the practical application of in situ polymerization methods in solid-state lithium-based batteries are reviewed.展开更多
Lithium-based batteries(LiBs)are integral components in operating electric vehicles to renewable energy systems and portable electronic devices,thanks to their unparalleled energy density,minimal self-discharge rates,...Lithium-based batteries(LiBs)are integral components in operating electric vehicles to renewable energy systems and portable electronic devices,thanks to their unparalleled energy density,minimal self-discharge rates,and favorable cycle life.However,the inherent safety risks and performance degradation of LiB over time impose continuous monitoring facilitated by sophisticated battery management systems(BMS).This review comprehensively analyzes the current state of sensor technologies for smart LiBs,focusing on their advancements,opportunities,and potential challenges.Sensors are classified into two primary groups based on their application:safety monitoring and performance optimization.Safety monitoring sensors,including temperature,pressure,strain,gas,acoustic,and magnetic sensors,focus on detecting conditions that could lead to hazardous situations.Performance optimization sensors,such as optical-based and electrochemical-based,monitor factors such as state of charge and state of health,emphasizing operational efficiency and lifespan.The review also highlights the importance of integrating these sensors with advanced algorithms and control approaches to optimize charging and discharge cycles.Potential advancements driven by nanotechnology,wireless sensor networks,miniaturization,and machine learning algorithms are also discussed.However,challenges related to sensor miniaturization,power consumption,cost efficiency,and compatibility with existing BMS need to be addressed to fully realize the potential of LiB sensor technologies.This comprehensive review provides valuable insights into the current landscape and future directions of sensor innovations in smart LiBs,guiding further research and development efforts to enhance battery performance,reliability,and safety.Integration of advanced sensor technologies for smart LiBs:integrating non-optical multi-parameter,optical-based,and electrochemical sensors within the BMS to achieve higher safety,improved efficiency,early warning mechanisms,and TR prevention.Potential advancements are driven by nanotechnology,wireless sensor networks,miniaturization,and advanced algorithms,addressing key challenges to enhance battery performance and reliability.展开更多
New catalysts combined with an organic or inorganic lithium salt (lithium acetate or lithiumchloride) and a conventional catalyst for the transesterification of dimethyl terephthalate withethylene glycol have been stu...New catalysts combined with an organic or inorganic lithium salt (lithium acetate or lithiumchloride) and a conventional catalyst for the transesterification of dimethyl terephthalate withethylene glycol have been studied. Reaction mechanism in presence of lithium-base catalyst hasbeen proposed. A synergistic action of two classes of catalysts creates the speed-up of initial re-action particularly in presence of lithium acetate. The presence of lithium base catalyst can re-duce diethylene glycol content and raise the melting point of final PET product, but almostuneffect PET molecular weight distribution.展开更多
The conventional design of metal-organic frameworks(MOFs)with room-temperature phosphorescence(RTP)mostly relies on using heavy metals,as the heavy atom effect can effectively increase the efficiency of intersystem cr...The conventional design of metal-organic frameworks(MOFs)with room-temperature phosphorescence(RTP)mostly relies on using heavy metals,as the heavy atom effect can effectively increase the efficiency of intersystem crossing(ISC)to get a better phosphorescence performance.For the first time,we reported the highly efficient RTP of a lithium-based MOF IMU-101 with a lifetime(τ)of 299 ms and a quantum yield(QY)of 4.91%.In addition,MOFs IMU-102 and IMU-103,with sodium and cesium as metal nodes,were successfully synthesized.The phosphorescence properties of this series of alkali metal MOFs were systematically studied and compared.The crystallography and computational calculation show that the mechanism for achieving RTP for this material lies in the ultrashort coordination bond of Li,which enables the reduction of non-radiative transitions.IMU-101,as a cheap and environmentally friendly room-temperature phosphorescent material,has been further developed into composite polymer inks and bulk materials.This makes them promising for applications in anti-counterfeiting and information encryption.展开更多
ZIF-8 is widely applied in lubrication,adsorption,and catalysis owing to its unique physicochemical properties.Previous experimental studies have demonstrated its feasibility as a lubricant additive.In the present wor...ZIF-8 is widely applied in lubrication,adsorption,and catalysis owing to its unique physicochemical properties.Previous experimental studies have demonstrated its feasibility as a lubricant additive.In the present work,the lubricating performance of ZIF-8 as an additive to lithiumbased grease is quantitatively and dynamically analyzed at the atomic scale using molecular dynamics simulations.Friction wear experiments are also conducted to elucidate the lubrication mechanism of ZIF-8.The simulation and experimental results indicate that the incorporation of ZIF-8 effectively enhances the antifriction and antiwear characteristics of lithium grease.The most significant improvement in the lubrication performance of the grease is obtained at a mass fraction of 2.0 wt.%ZIF-8,which reduces the friction factorof the grease by about 17.0%and the wear by40.0%.Furthermore,the molecular dynamics simulations reveal that ZIF-8 primarily functions as a ball bearing under low-load conditions.However,under high-load conditions,ZIF-8 undergoes significant deformation and primarily acts as a filler.This explains the experimentally observed significant reduction in friction coefficient after the addition of ZIF-8.The results of this study provide a theoretical foundation for the development of new environmentally friendly grease additives.展开更多
Effective passivation of aluminum(Al)current collector at high potentials(>4.0 V vs.Li/Li^(+))is of essence for the long-term operation of lithium-based batteries.Unfortunately,the non-aqueous liquid electrolytes c...Effective passivation of aluminum(Al)current collector at high potentials(>4.0 V vs.Li/Li^(+))is of essence for the long-term operation of lithium-based batteries.Unfortunately,the non-aqueous liquid electrolytes comprising lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)and organic carbonates are corrosive toward Al current collector at high potentials(>4.0 V vs.Li/Li^(+)),despite their intriguing features(e.g.,good chemical stability and high ionic conductivity).Herein,we propose the utilization of N,N-dimethyl fluorosulfonamide(DMFSA)as electrolyte solvent for suppressing Al corrosion in the LiTFSI-based electrolytes.It has been demonstrated that the electrolyte of 1.0 M LiTFSI-DMFSA shows decent ionic conductivities(1.76 mS·cm^(−1)at 25℃)with good fluidities(2.44 cP at 25℃).In particular,the replacement of organic carbonates(e.g.,ethylene carbonate and ethyl methyl carbonate)with DMFSA leads to significant suppressed Al corrosion.Morphological and compositional characterizations utilizing scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS)reveal that DMFSA favors the formation of insoluble species(i.e.,aluminum fluoride(AlF_(3)))on the surface of Al electrode,which effectively inhibits continuous exposure of fresh Al surface to electrolyte during cycling.This work provides not only a deeper understanding on the Al corrosion in LiTFSI-based electrolyte but also an elegant path to stabilize the Al current collector at high potentials(>4.0 V vs.Li/Li^(+)),which may give an impetus into the development of lithium-based batteries.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 52102280, U2030206, 11874254, 51622207)Shanghai Pujiang Program (No. 2019PJD016)+2 种基金Foundation of China Academy of Engineering Physics-Key Laboratory of Neutron Physics (No. 2019BB07)Scientific Research Project of Zhijiang Laboratory (No. 2021PE0AC02)supported by funding from King Abdullah University of Science and Technology (KAUST)。
文摘Lithium dendrite growth due to uneven electrodeposition usually leads to the potential hazard of internal short circuit and shorter lifetime of lithium-based batteries. Extensive efforts have been devoted to explore the effects of single or two factors on dendrite growth, involving the diffusion coefficient, exchange current density, electrolyte concentration, temperature, and applied voltage. However, these factors interrelate during battery operation, signifying that a understanding of how they jointly influence the electrodeposition is of paramount importance for the effective suppression of dendrites. Here, we incorporate the dependent relationships among key factors into the phase-field model to capture their synergistic effects on electrodeposition. All the simulations are implemented in our self-written MATLAB code under a unified modeling framework. Following this, five groups of experimentally common dendrite patterns are reproduced and the corresponding electrodeposition driving forces are identified. Unexpectedly, we find that with the decrease of the ratio of exchange current density(or applied voltage) to diffusion coefficient, the electrodeposition morphology changes from needle-like dendrites to columnar dendrites and to uniform deposition. The present phase-field simulation tends to depict the practical electrodeposition process, providing important insights into synergistic regulation to suppress dendrite growth.
基金financially supported by Wuxi Municipal Bureau on Science and Technology,China(Wuxi 530 project,20130529010040)Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(SJCX180734)。
文摘Graphite nanosheets with the average thicknesses ranging from 24.4 to 48.9 nm were prepared with the use of expanded graphite as the raw material by sand milling in deionized water,anhydrous ethanol,glycerol,and 1,4-butanediol,respectively.Anhydrous ethanol favored the formation of graphite nanosheets with a smaller average thickness.When the graphite nanosheets with the content of 2 wt%were added in lithium-based grease,the average friction coefficient decreased by 27%as compared with the pure lithium-based grease.The weld point and load wear index were 1.6 and 1.4 times those of the pure lithium-based grease,respectively.The tribological properties of the graphite nanosheet-containing lithium-based grease were comparable with those of the graphene-containing lithium-based grease.
基金This work is supported by Key R&D Project funded by Department of Science and Technology of Jiangsu Province(Grant No.BE2020003)Key Program-Automobile Joint Fund of National Natural Science Foundation of China(Grant No.U1964205)+5 种基金General Program of National Natural Science Foundation of China(Grant No.51972334)General Program of National Natural Science Foundation of Beijing(Grant No.2202058)Cultivation Project of Leading Innovative Experts in Changzhou City(Grant No.CQ20210003)National Overseas High-level Expert Recruitment Program(Grant No.E1JF021E11)Talent Program of Chinese Academy of Sciences,"Scientist Studio Program Funding"from Yangtze River Delta Physics Research Center and Tianmu Lake Institute of Advanced Energy Storage Technologies(Grant No.TIES-SS0001)Science and Technology Research Research Institute of China Three Gorges Corporation(Grant No.202103402).
文摘Sulfide solid electrolytes are widely regarded as one of the most promising technical routes to realize all-solid-state batteries(ASSBs)due to their high ionic conductivity and favorable deformability.However,the relatively high price of the crucial starting material,Li_(2)S,results in high costs of sulfide solid electrolytes,limiting their practical application in ASSBs.To solve this problem,we develop a new synthesis route of Li_(2)S via liquid-phase synthesis method,employing lithium and biphenyl in 1,2-dimethoxyethane(DME)ether solvent to form a lithium solution as the lithium precursor.Because of the comparatively strong reducibility of the lithium solution,its reaction with sulfur proceeds effectively even at room temperature.This new synthesis route of Li_(2)S starts with cheap precursors of lithium,sulfur,biphenyl and DME solvent,and the only remaining byproduct(DME solution of biphenyl)after the collection of Li_(2)S product can be recycled and reused.Besides,the reaction can proceed effectively at room temperature with mild condition,reducing energy cost to a great extent.The as-synthesized Li_(2)S owns uniform and extremely small particle size,proved to be feasible in synthesizing sulfide solid electrolytes(such as the solid-state synthesis of Li_(6)PS_(5)C_(l)).Spontaneously,this lithium solution can be directly employed in the synthesis of Li_(3)PS_(4) solid electrolytes via liquid-phase synthesis method,in which the centrifugation and heat treatment processes of Li_(2)S are not necessary,providing simplified production process.The as-synthesized Li_(3)PS_(4) exhibits typical Li+conductivity of 1.85×10^(-4) S·cm^(-1) at 30℃.
文摘The rapid evolution of lithium-ion batteries over the past decade,coupled with their extensive commercial utilization,has entrenched lithium-ion technology as a cornerstone in the energy-storage field.Despite this established position,the prevalence of liquid electrolytes in contemporary batteries has been beset by inherent vulnerabilities,including susceptibility to leakage,volatility,and combustibility.In response,polymer electrolytes have emerged as a promising alternative,distinguished by their superior safety profile,elevated energy density,and prolonged operational lifespan.Nevertheless,the widespread adoption of polymer electrolytes also has impediments such as constrained mobility and the propensity for forming lithium dendrite.Addressing these issues is paramount for the further advancement of polymer electrolyte technology.This review aims to provide a comprehensive elucidation of gel polymer electrolytes,solid polymer electrolytes,and composite polymer electrolytes,the predominant subclasses within the field of polymer electrolytes.A systematic exposition of diverse polymer electrolyte formulations,encompassing their respective merits and demerits alongside prospective applications,will be undertaken.Particular emphasis will be put on the strategies applied to ameliorate battery performance to delineate the avenues for potential enhancement in this critical domain.
基金We acknowledge financial support from the National Key R&D Program of China(2018YFA0209600)the Natural Science Foundation of China(22022813,21878268)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(2019R01006).
文摘Lithium-based batteries have had a profound impact on modern society through their extensive use in portable electronic devices,electric vehicles,and energy storage systems.However,battery safety issues such as thermal runaway,fire,and explosion hinder their practical application,especially for using metal anode.These problems are closely related to the high flammability of conventional electrolytes and have prompted the study of flameretardant and nonflammable electrolytes.Here,we review the recent research on nonflammable electrolytes used in lithium-based batteries,including phosphates,fluorides,fluorinated phosphazenes,ionic liquids,deep eutectic solvents,aqueous electrolytes,and solid-state electrolytes.Their flame-retardant mechanisms and efficiency are discussed,as well as their influence on cell electrochemical performance.We conclude with a summary of future prospects for the design of nonflammable electrolytes and the construction of safer lithium-based batteries.
基金supported by the National Key Research and Development Program of China(Grant/Award No.2021YFF0500600)National Natural Science Foundation of China(Grant/Award Nos.U2001220 and 52203298)+2 种基金Local Innovative Research Teams Project of Guangdong Pearl River Talents Program(Grant/Award No.2017BT01N111)Shenzhen All-Solid-State Lithium Battery Electrolyte Engineering Research Center(Grant/Award No.XMHT20200203006)Shenzhen Technical Plan Project(Grant/Award Nos.RCJC20200714114436091,JCYJ20220818101003007,JCYJ20220818101003008,and JCYJ20220530143012027).
文摘The application of lithium-based batteries is challenged by the safety issues of leakage and flammability of liquid electrolytes.Polymer electrolytes(PEs)can address issues to promote the practical use of lithium metal batteries.However,the traditional preparation of PEs such as the solution-casting method requires a complicated preparation process,especially resulting in side solvents evaporation issues.The large thickness of traditional PEs reduces the energy density of the battery and increases the transport bottlenecks of lithium-ion.Meanwhile,it is difficult to fill the voids of electrodes to achieve good contact between electrolyte and electrode.In situ polymerization appears as a facile method to prepare PEs possessing excellent interfacial compatibility with electrodes.Thus,thin and uniform electrolytes can be obtained.The interfacial impedance can be reduced,and the lithium-ion transport throughput at the interface can be increased.The typical in situ polymerization process is to implant a precursor solution containing monomers into the cell and then in situ solidify the precursor under specific initiating conditions,and has been widely applied for the preparation of PEs and battery assembly.In this review,we focus on the preparation and application of in situ polymerization method in gel polymer electrolytes,solid polymer electrolytes,and composite polymer electrolytes,in which different kinds of monomers and reactions for in situ polymerization are discussed.In addition,the various compositions and structures of inorganic fillers,and their effects on the electrochemical properties are summarized.Finally,challenges and perspectives for the practical application of in situ polymerization methods in solid-state lithium-based batteries are reviewed.
基金supported by the National Natural Science Foundation of China(NSFC,52130601)the Joint Research Center for Multi-energy Complementation and Conversion of USTC.
文摘Lithium-based batteries(LiBs)are integral components in operating electric vehicles to renewable energy systems and portable electronic devices,thanks to their unparalleled energy density,minimal self-discharge rates,and favorable cycle life.However,the inherent safety risks and performance degradation of LiB over time impose continuous monitoring facilitated by sophisticated battery management systems(BMS).This review comprehensively analyzes the current state of sensor technologies for smart LiBs,focusing on their advancements,opportunities,and potential challenges.Sensors are classified into two primary groups based on their application:safety monitoring and performance optimization.Safety monitoring sensors,including temperature,pressure,strain,gas,acoustic,and magnetic sensors,focus on detecting conditions that could lead to hazardous situations.Performance optimization sensors,such as optical-based and electrochemical-based,monitor factors such as state of charge and state of health,emphasizing operational efficiency and lifespan.The review also highlights the importance of integrating these sensors with advanced algorithms and control approaches to optimize charging and discharge cycles.Potential advancements driven by nanotechnology,wireless sensor networks,miniaturization,and machine learning algorithms are also discussed.However,challenges related to sensor miniaturization,power consumption,cost efficiency,and compatibility with existing BMS need to be addressed to fully realize the potential of LiB sensor technologies.This comprehensive review provides valuable insights into the current landscape and future directions of sensor innovations in smart LiBs,guiding further research and development efforts to enhance battery performance,reliability,and safety.Integration of advanced sensor technologies for smart LiBs:integrating non-optical multi-parameter,optical-based,and electrochemical sensors within the BMS to achieve higher safety,improved efficiency,early warning mechanisms,and TR prevention.Potential advancements are driven by nanotechnology,wireless sensor networks,miniaturization,and advanced algorithms,addressing key challenges to enhance battery performance and reliability.
文摘New catalysts combined with an organic or inorganic lithium salt (lithium acetate or lithiumchloride) and a conventional catalyst for the transesterification of dimethyl terephthalate withethylene glycol have been studied. Reaction mechanism in presence of lithium-base catalyst hasbeen proposed. A synergistic action of two classes of catalysts creates the speed-up of initial re-action particularly in presence of lithium acetate. The presence of lithium base catalyst can re-duce diethylene glycol content and raise the melting point of final PET product, but almostuneffect PET molecular weight distribution.
基金supported by the National Natural Science Foundation of China(22261037)the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT22091)+6 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2021BS02002)the Young Science and Technology Talents Cultivation Project of Inner Mongolia University(21221505)the Central Guidance on Local Science and Technology Development Fund of Inner Mongolia Autonomous Region(2023ZY0016)the Start-up Funding provided by Inner Mongolia Universitythe financial support from the National Natural Science Foundation of China(22361031)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2022QN02015)the Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region(NJZY22334)。
文摘The conventional design of metal-organic frameworks(MOFs)with room-temperature phosphorescence(RTP)mostly relies on using heavy metals,as the heavy atom effect can effectively increase the efficiency of intersystem crossing(ISC)to get a better phosphorescence performance.For the first time,we reported the highly efficient RTP of a lithium-based MOF IMU-101 with a lifetime(τ)of 299 ms and a quantum yield(QY)of 4.91%.In addition,MOFs IMU-102 and IMU-103,with sodium and cesium as metal nodes,were successfully synthesized.The phosphorescence properties of this series of alkali metal MOFs were systematically studied and compared.The crystallography and computational calculation show that the mechanism for achieving RTP for this material lies in the ultrashort coordination bond of Li,which enables the reduction of non-radiative transitions.IMU-101,as a cheap and environmentally friendly room-temperature phosphorescent material,has been further developed into composite polymer inks and bulk materials.This makes them promising for applications in anti-counterfeiting and information encryption.
基金supported by the National Natural Science Foundation of China(52275178)the Fujian Industry University Cooperation Project(2020H6025)。
文摘ZIF-8 is widely applied in lubrication,adsorption,and catalysis owing to its unique physicochemical properties.Previous experimental studies have demonstrated its feasibility as a lubricant additive.In the present work,the lubricating performance of ZIF-8 as an additive to lithiumbased grease is quantitatively and dynamically analyzed at the atomic scale using molecular dynamics simulations.Friction wear experiments are also conducted to elucidate the lubrication mechanism of ZIF-8.The simulation and experimental results indicate that the incorporation of ZIF-8 effectively enhances the antifriction and antiwear characteristics of lithium grease.The most significant improvement in the lubrication performance of the grease is obtained at a mass fraction of 2.0 wt.%ZIF-8,which reduces the friction factorof the grease by about 17.0%and the wear by40.0%.Furthermore,the molecular dynamics simulations reveal that ZIF-8 primarily functions as a ball bearing under low-load conditions.However,under high-load conditions,ZIF-8 undergoes significant deformation and primarily acts as a filler.This explains the experimentally observed significant reduction in friction coefficient after the addition of ZIF-8.The results of this study provide a theoretical foundation for the development of new environmentally friendly grease additives.
基金supported by the Fundamental Research Funds for the Central Universities,HUST(No.52020kfyXJJS09)。
文摘Effective passivation of aluminum(Al)current collector at high potentials(>4.0 V vs.Li/Li^(+))is of essence for the long-term operation of lithium-based batteries.Unfortunately,the non-aqueous liquid electrolytes comprising lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)and organic carbonates are corrosive toward Al current collector at high potentials(>4.0 V vs.Li/Li^(+)),despite their intriguing features(e.g.,good chemical stability and high ionic conductivity).Herein,we propose the utilization of N,N-dimethyl fluorosulfonamide(DMFSA)as electrolyte solvent for suppressing Al corrosion in the LiTFSI-based electrolytes.It has been demonstrated that the electrolyte of 1.0 M LiTFSI-DMFSA shows decent ionic conductivities(1.76 mS·cm^(−1)at 25℃)with good fluidities(2.44 cP at 25℃).In particular,the replacement of organic carbonates(e.g.,ethylene carbonate and ethyl methyl carbonate)with DMFSA leads to significant suppressed Al corrosion.Morphological and compositional characterizations utilizing scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS)reveal that DMFSA favors the formation of insoluble species(i.e.,aluminum fluoride(AlF_(3)))on the surface of Al electrode,which effectively inhibits continuous exposure of fresh Al surface to electrolyte during cycling.This work provides not only a deeper understanding on the Al corrosion in LiTFSI-based electrolyte but also an elegant path to stabilize the Al current collector at high potentials(>4.0 V vs.Li/Li^(+)),which may give an impetus into the development of lithium-based batteries.
