Greigite (Fe3S4) is thermodynamically stable: Implications for its terrestrial and planetary occurrence.
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ABSTRACT:
SUBMITTER: Subramani T
PROVIDER: S-EPMC7682356 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Transition metal dichalcogenide materials have been considered as promising anode materials for rechargeable sodium-ion batteries because of their high specific capacity and low cost. Here, we demonstrate an iron sulfide Fe3S4 as a new anode material for a rechargeable sodium-ion battery. The involved conversion mechanism has been proved when the as-prepared Fe3S4 was used as the host material for sodium storage. Remarkably, a compound FeS x with quantum size generated by conversion reaction overcame the kinetic and thermodynamic constraints of chemical conversion to achieve superior cycling and rate capability. As a result, the as-prepared Fe3S4 electrode delivers a high reversible specific capacity of 548 mA h g-1 at 0.2 A g-1, together with an excellent cycling stability of 275 mA h g-1 after 3500 cycles at 20 A g-1.
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