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Updated: Jun 30, 2025
09:41
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
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Boosting Multielectron Reaction Stability of Sodium Vanadium Phosphate by High-Entropy Substitution
Zhiqiang Hao1,2, Xiaoyan Shi1,2, Wenqing Zhu1,2
1Institute for Carbon Neutralization, College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, People's Republic of China.
ACS Nano
|March 22, 2024
Summary
High-entropy substitution and electrolyte optimization enhance sodium-ion battery cathodes. This strategy improves the stability and performance of sodium-vanadium phosphate (NVP) for long-lasting, high-power sodium-ion batteries (SIBs).
Area of Science:
- Materials Science
- Electrochemistry
- Energy Storage
Background:
- Sodium-ion batteries (SIBs) are promising for grid storage.
- Sodium-vanadium phosphate (NVP) is a potential cathode material but suffers from poor stability.
- Instability is linked to the V5+/V4+ redox couple reversibility and structural changes.
Purpose of the Study:
- To enhance the stability and electrochemical performance of NVP cathodes for SIBs.
- To investigate the synergistic effects of high-entropy substitution and electrolyte optimization.
- To understand the mechanisms behind improved performance.
Main Methods:
- High-entropy substitution was applied to NVP.
- Electrolyte optimization using a diglyme-based solvent was performed.
- In situ X-ray absorption near-edge structure (XANES) and in situ X-ray diffraction (XRD) were used for characterization.
Main Results:
- High-entropy substitution NVP (HE-NVP) demonstrated improved V5+/V4+ redox reversibility and structural stability.
- Electrochemical performance was significantly enhanced in the diglyme-based electrolyte.
- HE-NVP achieved 93.1% capacity retention after 2000 cycles and 120 mAh g-1 at 5.0 A g-1.
Conclusions:
- The combination of high-entropy substitution and electrolyte optimization is a powerful strategy for improving polyanionic cathodes in SIBs.
- HE-NVP exhibits excellent long cycle life and high power density.
- This approach offers a pathway for developing advanced cathode materials for SIBs.
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