Interfacial space charge storage between ionic and electronic conductor is a promising scheme to further improve energy and power density of alkali metal ion batteries(AMIBs).However,the general behavior of space char...Interfacial space charge storage between ionic and electronic conductor is a promising scheme to further improve energy and power density of alkali metal ion batteries(AMIBs).However,the general behavior of space charge storage in AMIBs has been less investigated experimentally,mostly due to the complicated electrochemical behavior and lack of proper characterization techniques.Here,we use operando magnetometry to verify that in FeSe_(2)AMIBs,abundant Li^(+)/Na^(+)/K^(+)(M^(+))can be stored at M_(2)Se phase while electrons accumulate at Fe nanoparticles,forming interfacial space charge layers.Magnetic and dynamics tests further demonstrate that with increasing ionic radius from Li^(+),Na^(+)to K^(+),the reaction kinetics can be hindered,resulting in limited Fe formation and reduced space charge storage capacity.This work lays solid foundation for studying the complex interfacial effect in electrochemical processes and designing advanced energy storage devices with substantial capacity and considerable power density.展开更多
基金supported by the National Natural Science Foundation of China(22179066,51804173,and 11674186)the National Science Foundation of Shandong Province(ZR2020MA073)+2 种基金the Science and Technology Board of Qingdao(16-5-1-2jch)Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery grant RGPIN-04178the Canada First Research Excellence Fund。
文摘Interfacial space charge storage between ionic and electronic conductor is a promising scheme to further improve energy and power density of alkali metal ion batteries(AMIBs).However,the general behavior of space charge storage in AMIBs has been less investigated experimentally,mostly due to the complicated electrochemical behavior and lack of proper characterization techniques.Here,we use operando magnetometry to verify that in FeSe_(2)AMIBs,abundant Li^(+)/Na^(+)/K^(+)(M^(+))can be stored at M_(2)Se phase while electrons accumulate at Fe nanoparticles,forming interfacial space charge layers.Magnetic and dynamics tests further demonstrate that with increasing ionic radius from Li^(+),Na^(+)to K^(+),the reaction kinetics can be hindered,resulting in limited Fe formation and reduced space charge storage capacity.This work lays solid foundation for studying the complex interfacial effect in electrochemical processes and designing advanced energy storage devices with substantial capacity and considerable power density.
