Manganese-based oxides are widely regarded as highly promising cathode materials for sodium-ion batteries due to their abundant resources,low cost and high specific capacity.Especially in the P2 and O3-type structures...Manganese-based oxides are widely regarded as highly promising cathode materials for sodium-ion batteries due to their abundant resources,low cost and high specific capacity.Especially in the P2 and O3-type structures,excellent electrochemical performance and structural stability are expected to be achieved by modulating the ratio of Mn to other transition metals.However,these materials are susceptible to phase transitions,Jahn-Teller distortions and manganese dissolution during cycling,which limits their structural stability and electrochemical performance.To solve these critical issues,researchers have proposed various material design and modulation strategies and achieved remarkable progress.This review provides a systematic summary of the current state of research on manganese-based oxides in sodium-ion batteries and offers a detailed analysis of the root causes of performance degradation in terms of material structural features,defect types and formation mechanisms.Meanwhile,the current research progress in ion doping,high entropy strategy,surface modification,and interfacial engineering is reviewed to explore the synergistic regulation on structural stability and electrochemical behavior.The unique advantages of these materials in terms of phase stability,rate capability and cycle life are demonstrated.Finally,this paper looks forward to the future research directions and development trends for manganese-based oxides,providing a theoretical foundation and technical support for the construction of high-performance and scalable cathode materials for sodium-ion batteries.展开更多
Perturbation is generally considered as the flow noise,and its energy can gain transient growth in the separation bubble.The amplified perturbations may cause unstable Kelvin–Helmohltz vortices which induce the three...Perturbation is generally considered as the flow noise,and its energy can gain transient growth in the separation bubble.The amplified perturbations may cause unstable Kelvin–Helmohltz vortices which induce the three-dimensional transition.Active control of noise amplification via dielectric barrier discharge plasma actuator in the flow over a square leading-edge flat plate is numerically studied.The actuator is installed near the plate leading-edge where the separation bubble is formed.The maximum energy amplification of perturbations is positively correlated with the separation bubble scale which decreases with the increasing control parameters.As the magnitude of noise amplification is reduced,the laminar-turbulent transition is successfully suppressed.展开更多
基金supported by the National Natural Science Foundation of China(no.52374301)the Open Project of Guangxi Key Laboratory of Electrochemical Energy Materials(no.GXUEEM2024001)+3 种基金the Natural Science Foundation of Hebei Province(no.E2024501010)the Shijiazhuang Basic Research Project(no.241790667A)the Fundamental Research Funds for the Central Universities(no.N2423013)the Performance Subsidy Fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(no.22567627H).
文摘Manganese-based oxides are widely regarded as highly promising cathode materials for sodium-ion batteries due to their abundant resources,low cost and high specific capacity.Especially in the P2 and O3-type structures,excellent electrochemical performance and structural stability are expected to be achieved by modulating the ratio of Mn to other transition metals.However,these materials are susceptible to phase transitions,Jahn-Teller distortions and manganese dissolution during cycling,which limits their structural stability and electrochemical performance.To solve these critical issues,researchers have proposed various material design and modulation strategies and achieved remarkable progress.This review provides a systematic summary of the current state of research on manganese-based oxides in sodium-ion batteries and offers a detailed analysis of the root causes of performance degradation in terms of material structural features,defect types and formation mechanisms.Meanwhile,the current research progress in ion doping,high entropy strategy,surface modification,and interfacial engineering is reviewed to explore the synergistic regulation on structural stability and electrochemical behavior.The unique advantages of these materials in terms of phase stability,rate capability and cycle life are demonstrated.Finally,this paper looks forward to the future research directions and development trends for manganese-based oxides,providing a theoretical foundation and technical support for the construction of high-performance and scalable cathode materials for sodium-ion batteries.
基金funded by the Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20133219110039)
文摘Perturbation is generally considered as the flow noise,and its energy can gain transient growth in the separation bubble.The amplified perturbations may cause unstable Kelvin–Helmohltz vortices which induce the three-dimensional transition.Active control of noise amplification via dielectric barrier discharge plasma actuator in the flow over a square leading-edge flat plate is numerically studied.The actuator is installed near the plate leading-edge where the separation bubble is formed.The maximum energy amplification of perturbations is positively correlated with the separation bubble scale which decreases with the increasing control parameters.As the magnitude of noise amplification is reduced,the laminar-turbulent transition is successfully suppressed.
