Frontiers in Chemistry (Aug 2018)

Nitrogen-Doped Carbon Coated WS2 Nanosheets as Anode for High-Performance Sodium-Ion Batteries

  • Yong Liu,
  • Huijie Wei,
  • Chao Wang,
  • Chao Wang,
  • Fei Wang,
  • Haichao Wang,
  • Wanhong Zhang,
  • Xianfu Wang,
  • Chenglin Yan,
  • Bok H. Kim,
  • Bok H. Kim,
  • Fengzhang Ren

DOI
https://doi.org/10.3389/fchem.2018.00236
Journal volume & issue
Vol. 6

Abstract

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Due to the cost-effectiveness of sodium source, sodium-ion batteries (SIBs) have attracted considerable attention. However, SIBs still have some challenges in competing with lithium-ion batteries for practical applications. Particularly, the high rate capability and cycling stability are posing big problems for SIBs. Here, nitrogen-doped carbon-coated WS2 nanosheets (WS2/NC) were successfully synthesized by a high-temperature solution method, followed by carbonization of polypyrrole. When used as anode electrodes for SIBs, WS2/NC composite exhibited high-rate capacity at 386 and 238.1 mAh g−1 at 50 and 2,000 mA g−1, respectively. Furthermore, even after 400 cycle, the composite electrode could still deliver a capacity of ~180.1 mAh g−1 at 1,000 mA g−1, corresponding to a capacity loss of 0.09% per cycle. The excellent electrochemical performance could be attributed to the synergistic effect of the highly conductive nature of the nitrogen-doped carbon-coating and WS2 nanosheets. Results showed that the WS2/NC nanosheets are promising electrode materials for SIBs application.

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