Lim, C. Y. J., Eng, A. Y. S., Handoko, A. D., Horia, R., & Seh, Z. W. (2021). Sulfurized Cyclopentadienyl Nanocomposites for Shuttle-Free Room-Temperature Sodium–Sulfur Batteries. Nano Letters, 21(24), 10538–10546. https://doi.org/10.1021/acs.nanolett.1c04182
A major challenge hindering the practical adoption of room-temperature sodium–sulfur batteries (NaSBs) is polysulfide dissolution and shuttling, which results in irreversible capacity decay and low Coulombic efficiencies. In this work, we demonstrate for the first time NaSBs using a ferrocene-derived amorphous sulfurized cyclopentadienyl composite (SCC) cathode. Polysulfide dissolution is eliminated via covalent bonding between the insoluble short-chain sulfur species and carbon backbone. Control experiments with a metal-free composite analogue determined that the iron species in the SCC does not have a significant role in polysulfide anchoring. Instead, the superior electrochemical performance is attributed to sulfur covalently bonded to carbon and the uniform nanoparticulate morphology of the SCC composite. In the carbonate-based electrolyte, a discharge capacity of 795 mAh g(S)–1 was achieved during early cycling at 0.2 C, and high Coulombic efficiencies close to 100% were maintained with capacity retention of 532 and 442 mAh g(S)–1 after 100 and 200 cycles, respectively.
This research / project is supported by the National Research Foundation - NRF Fellowship
Grant Reference no. : NRF-NRFF2017-04
This research is supported by core funding from: Central Research Fund Award
Grant Reference no. : NA