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Understanding rhombohedral iron hexacyanoferrate with three different sodium positions for high power and long stability sodium-ion battery

Journal Article


Abstract


  • © 2020 Elsevier B.V. Sodium iron hexacyanoferrate (NaFeHCF) has been considered as a potential cathode for sodium-ion batteries owing to its low-cost and easily prepared procedure. However, it is still challenging to achieve long cyclic stability and superior rate capability, and the sodium storage mechanism of sodium-rich NaFeHCF is still elusive. Herein, a sodium-rich NaFeHCF with rhombohedral structure is presented with excellent electrochemical performances within 2.0–4.2 V. The specific capacity of ~115 mA h g−1 is obtained by utilizing two plateaus around 2.9 and 4.06 V, respectively. Remarkable rate performance from 10 to 4000 mA g−1 and 1000 cycles with high capacity retention is achieved as well. Synchrotron powder X-ray diffraction (PXRD) and structural refinement reveals that sodium-ions occupy three different sites (interstitial, face and edge) in rhombohedral unit cell, which contribute different capacities on different plateaus during Na+ extractions. Moreover, the rhombohedral structure is well-maintained after long-term Na+ extractions/insertions and reversible phase transitions with small volume variation are observed through in-situ synchrotron PXRD. The kinetic properties of Na+ in rhombohedral unit cell are identified by ab-initio molecular dynamics method and density functional theory calculations, which indicate that Na+ transport on three-dimensional diffusion paths, thus enabling the outstanding rate performance of NaFeHCF.

Authors


  •   Wang, Wanlin (external author)
  •   Hu, Zhe (external author)
  •   Yan, Zichao (external author)
  •   Peng, Jian (external author)
  •   Chen, Mingzhe (external author)
  •   Lai, Weihong (external author)
  •   Gu, Qinfen (external author)
  •   Chou, Shulei
  •   Liu, Hua K.
  •   Dou, Shi Xue

Publication Date


  • 2020

Citation


  • Wang, W., Hu, Z., Yan, Z., Peng, J., Chen, M., Lai, W., Gu, Q., Chou, S., Liu, H. & Dou, S. (2020). Understanding rhombohedral iron hexacyanoferrate with three different sodium positions for high power and long stability sodium-ion battery. Energy Storage Materials, 30 42-51.

Scopus Eid


  • 2-s2.0-85084678946

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/4159

Number Of Pages


  • 9

Start Page


  • 42

End Page


  • 51

Volume


  • 30

Place Of Publication


  • Netherlands

Abstract


  • © 2020 Elsevier B.V. Sodium iron hexacyanoferrate (NaFeHCF) has been considered as a potential cathode for sodium-ion batteries owing to its low-cost and easily prepared procedure. However, it is still challenging to achieve long cyclic stability and superior rate capability, and the sodium storage mechanism of sodium-rich NaFeHCF is still elusive. Herein, a sodium-rich NaFeHCF with rhombohedral structure is presented with excellent electrochemical performances within 2.0–4.2 V. The specific capacity of ~115 mA h g−1 is obtained by utilizing two plateaus around 2.9 and 4.06 V, respectively. Remarkable rate performance from 10 to 4000 mA g−1 and 1000 cycles with high capacity retention is achieved as well. Synchrotron powder X-ray diffraction (PXRD) and structural refinement reveals that sodium-ions occupy three different sites (interstitial, face and edge) in rhombohedral unit cell, which contribute different capacities on different plateaus during Na+ extractions. Moreover, the rhombohedral structure is well-maintained after long-term Na+ extractions/insertions and reversible phase transitions with small volume variation are observed through in-situ synchrotron PXRD. The kinetic properties of Na+ in rhombohedral unit cell are identified by ab-initio molecular dynamics method and density functional theory calculations, which indicate that Na+ transport on three-dimensional diffusion paths, thus enabling the outstanding rate performance of NaFeHCF.

Authors


  •   Wang, Wanlin (external author)
  •   Hu, Zhe (external author)
  •   Yan, Zichao (external author)
  •   Peng, Jian (external author)
  •   Chen, Mingzhe (external author)
  •   Lai, Weihong (external author)
  •   Gu, Qinfen (external author)
  •   Chou, Shulei
  •   Liu, Hua K.
  •   Dou, Shi Xue

Publication Date


  • 2020

Citation


  • Wang, W., Hu, Z., Yan, Z., Peng, J., Chen, M., Lai, W., Gu, Q., Chou, S., Liu, H. & Dou, S. (2020). Understanding rhombohedral iron hexacyanoferrate with three different sodium positions for high power and long stability sodium-ion battery. Energy Storage Materials, 30 42-51.

Scopus Eid


  • 2-s2.0-85084678946

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/4159

Number Of Pages


  • 9

Start Page


  • 42

End Page


  • 51

Volume


  • 30

Place Of Publication


  • Netherlands