Cobalt Single Atoms Supported on N-doped Carbon as an Active and Resilient Sulfur Host for Lithium–Sulfur Batteries
Author ORCID Identifier
Energy Storage Materials
Lithium-sulfur chemistry is currently being explored as a mechanism for electricity storage because it promises high energy capacities and low costs. However, practical applications of lithium-sulfur batteries (LSBs) are severely limited by the short cycle life caused by the polysulfide shuttling (PSS) effect. Herein, we report on a PSS-resistant yet redox-active sulfur host containing N-doped carbon dodecahedra supported cobalt single atoms (denoted as Co–SAs@NC) derived from a binary Co–Zn MOF-precursor. The results show that the sulfur cathode built on the Co–SAs@NC is electrocatalytically active towards soluble-polysulfides-to-insoluble-Li2S conversion, thus mitigating the detrimental PSS effect. The LSB using this new sulfur host exhibits a 600-cycle stable operation with a capacity of 737 mAh g−1 at 1C and 2.0 mg cm−2 S-loading. At a higher sulfur loading of 5.0 mg cm−2, it can still deliver a high initial discharge capacity of 1069 mAh g−1 at 0.1C and maintain 400 mAh g−1 at 1C for 150 cycles. Theoretical analysis suggests that the Co–N4 moiety in the Co–SAs@NC is fundamentally responsible for the observed activity and stability.
Binary Co–Zn MOF-Precursor, Li–S batteries, Redox kinetics, Single Co atoms, Stability
Li, Yijuan; Chen, Guilin; Mou, Jirong; Liu, Yanzhen; Xue, Shoufeng; Tan, Ting; Zhong, Wentao; Deng, Qiang; Li, Tao; Hu, Junhua; Yang, Chenghao; Huang, Kevin; and Liu, Meilin, "Cobalt Single Atoms Supported on N-doped Carbon as an Active and Resilient Sulfur Host for Lithium–Sulfur Batteries" (2020). NIU Bibliography. 381.
Department of Chemistry and Biochemistry