Interface Engineering of Fe₇S₈/FeS₂ Heterostructure in situ Encapsulated into Nitrogen-Doped Carbon Nanotubes for High Power Sodium-Ion Batteries.

ABSTRACT: Heterostructure engineering combined with carbonaceous materials shows great promise toward promoting sluggish kinetics, improving electronic conductivity, and mitigating the huge expansion of transition metal sulfide electrodes for high-performance sodium storage. Herein, the iron sulfide-based heterostructures in situ hybridized with nitrogen-doped carbon nanotubes (Fe₇S₈/FeS₂/NCNT) have been prepared through a successive pyrolysis and sulfidation approach. The Fe₇S₈/FeS₂/NCNT heterostructure delivered a high reversible capacity of 403.2 mAh g^-1 up to 100 cycles at 1.0 A g^-1 and superior rate capability (273.4 mAh g^-1 at 20.0 A g^-1) in ester-based electrolyte. Meanwhile, the electrodes also demonstrated long-term cycling stability (466.7 mAh g^-1 after 1,000 cycles at 5.0 A g^-1) and outstanding rate capability (536.5 mAh g^-1 at 20.0 A g^-1) in ether-based electrolyte. This outstanding performance could be mainly attributed to the fast sodium-ion diffusion kinetics, high capacitive contribution, and convenient interfacial dynamics in ether-based electrolyte.

SUBMITTER: Song P 

PROVIDER: S-EPMC10149539 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature