FeSex-SnSe/C nanofibers decorated with selenium-doped carbon nanosheets as advanced anode materials for lithium/potassium ion batteries

In this paper, a novel selenium-doped carbon nanosheet-decorated FeSe x -SnSe/C nanofibers (FeSnSe/SCNFs) composites have been prepared by electrostatic spinning. The unique morphology and structure endow the material with good electrochemical properties. The composite designated as FeSnSe/SCNFs-1, which has a molar ratio of 2:1 between Fe and Sn, performs best electrochemically. FeSnSe/SCNFs-1 anodes show a high reversible capacity of 816.1 mAh g −1 at 100 mA g −1 in lithium-ion batteries, and maintain a capacity of 414.8 mAh g −1 at 5000 mA g −1 . After 800 cycles at 1000 mA g −1 , it exhibits a capacity of 551.8 mAh g −1 , and after 100 cycles in potassium ion batteries at 100 mA g −1 , the capacity is 316.3 mAh g −1 with a retention rate of 90.5 % compared to the second cycle's capacity. This paper offers a novel approach to enhancing metal selenides' anode material performance for lithium/potassium ion batteries.