Solid electrolytes have gained attention recently for the development of next-generation Li-ion batteries since they can fun-damentally improve the battery stability and safety.Among various types of solid electrolyte...Solid electrolytes have gained attention recently for the development of next-generation Li-ion batteries since they can fun-damentally improve the battery stability and safety.Among various types of solid electrolytes,composite solid electrolytes(CSEs)exhibit both high ionic conductivity and excellent interfacial contact with the electrodes.Incorporating active nanofib-ers into the polymer matrix demonstrates an effective method to fabricate CSEs.However,current CSEs based on traditional poly(ethylene oxide)(PEO)polymer suffer from the poor ionic conductivity of PEO and agglomeration effect of inorganic fillers at high concentrations,which limit further improvements in Li+conductivity and electrochemical stability.Herein,we synthesize a novel PEO based cross-linked polymer(CLP)as the polymer matrix with naturally amorphous structure and high room-temperature ionic conductivity of 2.40×10^(−4)S cm^(−1).Li_(0.3)La_(0.557)TiO_(3)(LLTO)nanofibers are incorporated into the CLP matrix to form composite solid electrolytes,achieving enhanced ionic conductivity without showing filler agglomeration.The high content of Li-conductive nanofibers improves the mechanical strength,ensures the conductive network,and increases the total Li+conductivity to 3.31×10^(−4)S cm^(−1).The all-solid-state Li|LiFePO_(4)batteries with LLTO nanofiber-incorporated CSEs are able to deliver attractive specific capacity of 147 mAh g^(−1)at room temperature,and no evident dendrite is found at the anode/electrolyte interface after 100 cycles.展开更多
Supramolecular polymer networks(SPNs)are celebrated for their dynamic nature,yet they often exhibit inadequate mechanical properties.Thus far,the quest to bolster the mechanical resilience of SPNs while preserving the...Supramolecular polymer networks(SPNs)are celebrated for their dynamic nature,yet they often exhibit inadequate mechanical properties.Thus far,the quest to bolster the mechanical resilience of SPNs while preserving their dynamic character presents a formidable challenge.Herein,we introduce[2]rotaxane into SPN to serve as another cross-link,which could effectively enhance the mechanical robustness of the polymer network without losing the dynamic properties.Compared with SPN,the dually cross-linked network(DPN)demonstrates superior breaking strength,Young’s modulus,puncture force and toughness,underscoring its superior robustness.Furthermore,the cyclic tensile tests reveal that the energy dissipation capacity of DPN rivals,and in some cases surpasses,that of SPN,owing to the efficient energy dissipation pathway facilitated by[2]rotaxane.In addition,benefiting from stable topological structure of[2]rotaxane,DPN exhibits accelerated recovery from deformation,indicating superior elasticity compared to SPN.This strategy elevates the performance of SPNs across multiple metrics,presenting a promising avenue for the development of high-performance dynamic materials.展开更多
Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage capability.Herein,a series of precursor membranes with high porosity were produced using ...Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage capability.Herein,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical properties.The obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 C.These results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.展开更多
Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene （CLPS） as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysila...Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene （CLPS） as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane （VTES）, vinyl trimethoxysilane （VTMS） and γ-methacryloylpropyl trimethoxysilane （MPS）. The treated glass fibers were analyzed by fourier transform infrared spectroscopy （FTIR）. Dynamic mechanical thermal analysis （DMTA） and thermo-gravimetric analysis （TGA） were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy （SEM）. The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.展开更多
The viscosity property of Cr^3＋, Al^3＋, and compound ion cross-linked polymer gel solution in the anaerobic and aerobic environment was investigated aiming at meeting the practical demand of the oil field. The visco...The viscosity property of Cr^3＋, Al^3＋, and compound ion cross-linked polymer gel solution in the anaerobic and aerobic environment was investigated aiming at meeting the practical demand of the oil field. The viscosity reserving effect after adding the biocide and the gelation in the anaerobic and aerobic environments was also studied in the paper. The results indicate that the viscosity of the cross-linked polymer gel solution caused by the water produced in aerobic environment is higher than that in anaerobic environment, and that the viscosity value of the cross-linked polymer gel solutions after adding biocides has improved to some extent and polymer gel has gelated well in anaerobic environment.展开更多
基金the Department of Energy,Office of Energy Efficiency and Renewable Energy(EERE),under Award Number DE-EE0007806.
文摘Solid electrolytes have gained attention recently for the development of next-generation Li-ion batteries since they can fun-damentally improve the battery stability and safety.Among various types of solid electrolytes,composite solid electrolytes(CSEs)exhibit both high ionic conductivity and excellent interfacial contact with the electrodes.Incorporating active nanofib-ers into the polymer matrix demonstrates an effective method to fabricate CSEs.However,current CSEs based on traditional poly(ethylene oxide)(PEO)polymer suffer from the poor ionic conductivity of PEO and agglomeration effect of inorganic fillers at high concentrations,which limit further improvements in Li+conductivity and electrochemical stability.Herein,we synthesize a novel PEO based cross-linked polymer(CLP)as the polymer matrix with naturally amorphous structure and high room-temperature ionic conductivity of 2.40×10^(−4)S cm^(−1).Li_(0.3)La_(0.557)TiO_(3)(LLTO)nanofibers are incorporated into the CLP matrix to form composite solid electrolytes,achieving enhanced ionic conductivity without showing filler agglomeration.The high content of Li-conductive nanofibers improves the mechanical strength,ensures the conductive network,and increases the total Li+conductivity to 3.31×10^(−4)S cm^(−1).The all-solid-state Li|LiFePO_(4)batteries with LLTO nanofiber-incorporated CSEs are able to deliver attractive specific capacity of 147 mAh g^(−1)at room temperature,and no evident dendrite is found at the anode/electrolyte interface after 100 cycles.
基金support from the National Natural Science Foundation of China(Nos.22122105 and22071152)Natural Science Foundation of Shanghai(No.22dz1207603)+4 种基金the Shuguang Program of Shanghai Education Development Foundation and the Shanghai Municipal Education Commission(No.22SG11)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(No.SN-ZJU-SIAS-006)L.Y.acknowledges the financial support from the National Natural Science Foundation of China(No.22305150)Z.Z.acknowledges the financial support from the National Natural Science Foundation of China(Nos.22101175 and 52333001)supported by State Key Laboratory of Polyolefins and Catalysis and Shanghai Key Laboratory of Catalysis Technology for Polyolefins(No.SKL-LCTP-202301)。
文摘Supramolecular polymer networks(SPNs)are celebrated for their dynamic nature,yet they often exhibit inadequate mechanical properties.Thus far,the quest to bolster the mechanical resilience of SPNs while preserving their dynamic character presents a formidable challenge.Herein,we introduce[2]rotaxane into SPN to serve as another cross-link,which could effectively enhance the mechanical robustness of the polymer network without losing the dynamic properties.Compared with SPN,the dually cross-linked network(DPN)demonstrates superior breaking strength,Young’s modulus,puncture force and toughness,underscoring its superior robustness.Furthermore,the cyclic tensile tests reveal that the energy dissipation capacity of DPN rivals,and in some cases surpasses,that of SPN,owing to the efficient energy dissipation pathway facilitated by[2]rotaxane.In addition,benefiting from stable topological structure of[2]rotaxane,DPN exhibits accelerated recovery from deformation,indicating superior elasticity compared to SPN.This strategy elevates the performance of SPNs across multiple metrics,presenting a promising avenue for the development of high-performance dynamic materials.
基金financially supported by the National Natural Science Foundation of China(Nos.21574087 and 51973128)Science and Technology Department of Sichuan Province(Nos.2019YJ0128 and 2019YFG0277)supports from the Fundamental Research Funds for the Central Universities。
文摘Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage capability.Herein,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical properties.The obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 C.These results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.
基金Supported by National Natural Science Foundation of China (No.50872101,A3 Foresight Program-50821140308)National Basic Research Program of China (No.2009CB939704)a joint project of National Nature Science Foundation of China and Russian Foundation for Basic Research(No.NSFC-RFBR 51011120252)
文摘Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene （CLPS） as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane （VTES）, vinyl trimethoxysilane （VTMS） and γ-methacryloylpropyl trimethoxysilane （MPS）. The treated glass fibers were analyzed by fourier transform infrared spectroscopy （FTIR）. Dynamic mechanical thermal analysis （DMTA） and thermo-gravimetric analysis （TGA） were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy （SEM）. The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.
基金the Chinese National Natural Science Foundation(No.50634020)Scientific and Technological Project of China National Offshore Oil Corporation(No.SC06TJ-PWL-080).
文摘The viscosity property of Cr^3＋, Al^3＋, and compound ion cross-linked polymer gel solution in the anaerobic and aerobic environment was investigated aiming at meeting the practical demand of the oil field. The viscosity reserving effect after adding the biocide and the gelation in the anaerobic and aerobic environments was also studied in the paper. The results indicate that the viscosity of the cross-linked polymer gel solution caused by the water produced in aerobic environment is higher than that in anaerobic environment, and that the viscosity value of the cross-linked polymer gel solutions after adding biocides has improved to some extent and polymer gel has gelated well in anaerobic environment.
