Vanadium multiredox‐based NASICON‐Na
Sodium superionic conductor (NASICON)‐type materials are getting more and more attention due to their high capacity and good cycling ability compared with other cathode materials in aqueous zinc ion batteries (AZIB). The present paper was to study the synthesis and electrochemical properties of two NASICON compounds of Na3V2(PO4)3and Na3V2(PO4)2F3and to understand the impacts of fluorine. Both Na3V2(PO4)3and Na3V2(PO4)2F3are synthesized by hydrothermal growth followed with annealing at 800°C in inert gas. With 3 mol/L Zn(CF3SO3)2in water as electrolyte, Na3V2(PO4)3offered a high storage capacity, while Na3V2(PO4)2F3demonstrated a high discharge voltage though low storage capacity. It was also found that the storage capacity of Na3V2(PO4)2F3increases with increased cycles; however, the compound undergoes a gradual phase transition. It is discussed possible approaches to attain both high discharge voltage and large capacity with good cycling stability.
more » « less- Award ID(s):
- 1803256
- NSF-PAR ID:
- 10450678
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Energy Science & Engineering
- Volume:
- 9
- Issue:
- 7
- ISSN:
- 2050-0505
- Page Range / eLocation ID:
- p. 938-949
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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