Constructing potential anodes for sodium-ion batteries(SIBs)with a wide temperature property has captured enormous interests in recent years.Fe1-xS,a zero-band gap material confirmed by density states calculation,is a...Constructing potential anodes for sodium-ion batteries(SIBs)with a wide temperature property has captured enormous interests in recent years.Fe1-xS,a zero-band gap material confirmed by density states calculation,is an ideal electrode for fast energy storage on account of its low cost and high theoretical capacity.Herein,Fe1-xS nanosheet wrapped by nitrogen-doped carbon(Fe1-xS@NC)is engineered through a post-sulfidation strategy using Fe-based metal-organic framework(Fe-MOF)as the precursor.The obtained Fe1-xS@NC agaric-like structure can well shorten the charge diffusion pathway,and significantly enhance the ionic/electronic conductivities and the reaction kinetics.As expected,the Fe1-xS@NC electrode,as a prospective SIB anode,delivers a desirable capacity up to 510.2 mA h g^-1 at a high rate of8000 mA g^-1.Additionally,even operated at low temperatures of 0 and-25°C,high reversible capacities of 387.1 and 223.4 mA h g^-1 can still be obtained at 2000 mA g^-1,respectively,indicating its huge potential use at harsh temperatures.More noticeably,the full battery made by the Fe1-xS@NC anode and Na3 V2(PO4)2 O2 F cathode achieves a remarkable rate capacity(186.8 mA h g^-1 at 2000 m A g^-1)and an impressive cycle performance(183.6 m A h g^-1 after 100 cycles at700 mA g^-1)between 0.3 and 3.8 V.Such excellent electrochemical performance is mainly contributed by its pseudocapacitive-dominated behavior,which brings fast electrode kinetics and robust structural stability to the whole electrode.展开更多
基金financially supported by the National Natural Science Foundation of China (21873018, 21573036 and 21274017)the open project of Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis (130028655)
文摘Constructing potential anodes for sodium-ion batteries(SIBs)with a wide temperature property has captured enormous interests in recent years.Fe1-xS,a zero-band gap material confirmed by density states calculation,is an ideal electrode for fast energy storage on account of its low cost and high theoretical capacity.Herein,Fe1-xS nanosheet wrapped by nitrogen-doped carbon(Fe1-xS@NC)is engineered through a post-sulfidation strategy using Fe-based metal-organic framework(Fe-MOF)as the precursor.The obtained Fe1-xS@NC agaric-like structure can well shorten the charge diffusion pathway,and significantly enhance the ionic/electronic conductivities and the reaction kinetics.As expected,the Fe1-xS@NC electrode,as a prospective SIB anode,delivers a desirable capacity up to 510.2 mA h g^-1 at a high rate of8000 mA g^-1.Additionally,even operated at low temperatures of 0 and-25°C,high reversible capacities of 387.1 and 223.4 mA h g^-1 can still be obtained at 2000 mA g^-1,respectively,indicating its huge potential use at harsh temperatures.More noticeably,the full battery made by the Fe1-xS@NC anode and Na3 V2(PO4)2 O2 F cathode achieves a remarkable rate capacity(186.8 mA h g^-1 at 2000 m A g^-1)and an impressive cycle performance(183.6 m A h g^-1 after 100 cycles at700 mA g^-1)between 0.3 and 3.8 V.Such excellent electrochemical performance is mainly contributed by its pseudocapacitive-dominated behavior,which brings fast electrode kinetics and robust structural stability to the whole electrode.