论文部分内容阅读
Tin-based compounds are deemed as suitable anode candidates affording promising sodium-ion storages for rechargeable batteries and hybrid capacitors.However,synergistically tailoring the electrical conductivity and structural stability of tin-based anodes to attain durable sodium-ion storages remains challenging to date for its practical applications.Herein,metal-organic framework (MOF) derived SnSe/C wrapped within nitrogen-doped graphene (NG@SnSe/C) is designed targeting durable sodium-ion storage.NG@SnSe/C possesses favorable electrical conductivity and structure stability due to the inner carbon framework from the MOF thermal treatment and outer graphitic cage from the direct chemical vapor deposition synthesis.Consequently,NG@SnSe/C electrode can obtain a high reversible capacity of 650 mAh·g-1 at 0.05 A·g-1,a favorable rate performance of 287.8 mAh·g-1 at 5 A·g-1 and a superior cycle stability with a negligible capacity decay of 0.016％ per cycle over 3,200 cycles at 0.4 A·g-1.Theoretical calculations reveal that the nitrogen-doping in graphene can stabilize the NG@SnSe/C structure and improve the electrical conductivity.The reversible Na-ion storage mechanism of SnSe is further investigated by in-situ X-ray diffraction/ex-situ transmission electron microscopy.Furthermore,assembled sodium-ion hybrid capacitor full-cells comprising our NG@SnSe/C anode and an active carbon cathode harvest a high energy/power density of 115.5 Wh·kg-1/5,742 W·kg-1,holding promise for next-generation energy storages.