The separator is a key component of sodium-ion battery,which greatly affects the electrochemical performances and safety characteristics of the battery.Conventional glass fiber separator cannot meet the requirements o...The separator is a key component of sodium-ion battery,which greatly affects the electrochemical performances and safety characteristics of the battery.Conventional glass fiber separator cannot meet the requirements of large-scale application because of high cost and poor mechanical properties.Herein,the novel composite separators are prepared by a simple slurry sieving process using glass fiber separator scraps and ordinary qualitative filter paper as raw materials.As the composite mass ratio is 1:1,the composite separator has excellent comprehensive properties,including tensile strength of 15.8 MPa,porosity of 74.3%,ionic conductivity of 1.57×10^(-3)S·cm^(-1)and thermal stability at 210℃.The assembled sodium-ion battery shows superior cycling performance(capacity retention of 94.1%after 500 cycles at 1C)and rate capacity(retention rate of 87.3%at 10C),and it maintains fine interface stability.The above results provide some new ideas for the separator design of high-performance and low-cost sodium-ion batteries.展开更多
Spin glasses(SGs),generally defined as disordered systems with randomized competing interactions,are widely investigated complex phenomena.Discovering the ground states of spin glasses is crucial for understanding the...Spin glasses(SGs),generally defined as disordered systems with randomized competing interactions,are widely investigated complex phenomena.Discovering the ground states of spin glasses is crucial for understanding the nature of disordered magnets and many other physical manifestations,while also helping to solve some hard combinatorial optimization problems across multiple disciplines.However,the intrinsic cause of SG has always been elusive,especially in spinel oxide systems.Herein,we report the SG behavior observed in the cubic spinel oxides CoCrGaO_(4),and provide a comprehensive understanding of its intrinsic source.Magnetic results indicate a frustrated state under multi-magnetic competition,and the features of SG are confirmed by susceptibility tests.The fitting parameters ofτ0,T0,and zv of isothermal remanent magnetization further reveal the relaxation behavior and strong spin frustration.Furthermore,the varying exchange coupling under different temperatures and magnetic fields is unveiled,which should be responsible for the disordered state.Our studies unravel the underlying mechanism responsible for doping-induced magnetic frustration and introduce CoCrGaO_(4)as a potential platform for investigating spin glass behavior,thereby advancing fundamental research on frustrated magnetism within the spinel system.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos.52002106,22262013,and 52102261)the Talent Project of Anhui Provincial Department of Education (Nos.gxyqZD2021127 and gxbjZ D2022050)+1 种基金the Natural Science Foundation of Anhui Province,China (Nos.2108085QB68,2208085QB34,and2022AH052157)the Research Funds for Hefei Normal University (Nos.14098100 and 2021cyxy061)。
文摘The separator is a key component of sodium-ion battery,which greatly affects the electrochemical performances and safety characteristics of the battery.Conventional glass fiber separator cannot meet the requirements of large-scale application because of high cost and poor mechanical properties.Herein,the novel composite separators are prepared by a simple slurry sieving process using glass fiber separator scraps and ordinary qualitative filter paper as raw materials.As the composite mass ratio is 1:1,the composite separator has excellent comprehensive properties,including tensile strength of 15.8 MPa,porosity of 74.3%,ionic conductivity of 1.57×10^(-3)S·cm^(-1)and thermal stability at 210℃.The assembled sodium-ion battery shows superior cycling performance(capacity retention of 94.1%after 500 cycles at 1C)and rate capacity(retention rate of 87.3%at 10C),and it maintains fine interface stability.The above results provide some new ideas for the separator design of high-performance and low-cost sodium-ion batteries.
基金supported by the National Natural Science Foundation of China(Nos.12305369,12404129,22262013 and U1632161)High-level Talent Research Initiation Fund Project(No.2024rcjj03)+1 种基金the Project of Anhui Provincial Department of Education(Nos.2023AH010048 and gxbjZD2022050)the University Natural Science Research Project of Anhui Province(No.2023AH051278).
文摘Spin glasses(SGs),generally defined as disordered systems with randomized competing interactions,are widely investigated complex phenomena.Discovering the ground states of spin glasses is crucial for understanding the nature of disordered magnets and many other physical manifestations,while also helping to solve some hard combinatorial optimization problems across multiple disciplines.However,the intrinsic cause of SG has always been elusive,especially in spinel oxide systems.Herein,we report the SG behavior observed in the cubic spinel oxides CoCrGaO_(4),and provide a comprehensive understanding of its intrinsic source.Magnetic results indicate a frustrated state under multi-magnetic competition,and the features of SG are confirmed by susceptibility tests.The fitting parameters ofτ0,T0,and zv of isothermal remanent magnetization further reveal the relaxation behavior and strong spin frustration.Furthermore,the varying exchange coupling under different temperatures and magnetic fields is unveiled,which should be responsible for the disordered state.Our studies unravel the underlying mechanism responsible for doping-induced magnetic frustration and introduce CoCrGaO_(4)as a potential platform for investigating spin glass behavior,thereby advancing fundamental research on frustrated magnetism within the spinel system.
