Yolk-shell N-doped carbon coated FeS<inf>2</inf> nanocages as a high-performance anode for sodium-ion batteries

Publication Type:
Journal Article
Journal of Materials Chemistry A, 2019, 7 (23), pp. 14051 - 14059
Issue Date:
Filename Description Size
c9ta03917a.pdfPublished Version1.68 MB
Adobe PDF
Full metadata record
© 2019 The Royal Society of Chemistry. Pyrite FeS2 displays brilliant prospects for sodium storage because of its high theoretical capacity (894 mA h g-1), low cost and eco-friendly properties. The practical application of FeS2, however, has been thwarted by poor cycle life derived from the large volume change and active sulfide loss upon sodiation/desodiation. Herein, we fabricated yolk-shell nitrogen-doped carbon-coated FeS2 nanocages (PFS@NC) by a facile thermal-sulfurization of polypyrrole-coated Prussian blue precursors for sodium-ion batteries. The yolk-shell structure affords enough space to buffer the volumetric change of FeS2 nanoparticles during the sodiation process. Therefore, the structural integrity of PFS@NC can be preserved without deforming the carbon shell. Additionally, the nitrogen-doped carbon not only improves the electronic conductivity of the composite, but also effectively traps the soluble reduced products of FeS2, contributing to its stable cycling performance. As a result, a high specific capacity of 375 mA h g-1 has been achieved up to 1000 cycles at 5 A g-1 (92% capacity retention). The PFS@NC composite could be an excellent anode material for sodium storage and the as-developed synthetic strategy is expected to be utilized for improving the performance of other metal sulfide electrode materials.
Please use this identifier to cite or link to this item: