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Updated: Jun 15, 2026
05:47
Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
8.2K
A General Chemical Prepotassiation Strategy for Boosting the Zn-Storage Performance of Polymorphic MnO2 Cathodes.
Zu Chang1, Qian Zhang1, Luqi Zhou1
1Hubei Key Laboratory of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei, China.
Angewandte Chemie (International Ed. in English)
|March 17, 2026
Summary
A new mild chemical method rapidly inserts potassium ions into manganese dioxide cathodes, significantly boosting performance for aqueous zinc-ion batteries (AZIBs) by improving ion diffusion and structural stability.
Area of Science:
- Materials Science
- Electrochemistry
- Energy Storage
Background:
- Manganese dioxide (MnO2) cathodes face limitations in aqueous zinc-ion batteries (AZIBs) due to slow zinc-ion diffusion and poor structural stability.
- Conventional ion pre-intercalation methods require harsh conditions, hindering scalability and material quality.
Purpose of the Study:
- To develop a mild and efficient chemical prepotassiation strategy for MnO2 cathodes.
- To enhance the electrochemical performance of MnO2-based cathodes for AZIBs.
Main Methods:
- A novel mild chemical prepotassiation strategy using 9-fluorenone potassium (FL-K) as a K+/e- donor.
- Rapid (30 s) and quantitative K+ insertion into various MnO2 polymorphs (α-, γ-, δ-phases) under ambient conditions.
Main Results:
- Pre-intercalated K+ ions act as structural pillars, increasing spacing and conductivity.
- Optimized α-K0.05MnO2 cathode shows significantly improved rate capability (97.5 mAh g-1 at 10C) and cycling stability (64.5% retention after 300 cycles at 3C).
- Performance surpasses pristine α-MnO2.
Conclusions:
- The FL-K prepotassiation strategy offers a sustainable and universal protocol for high-performance intercalation-type electrode materials.
- This method overcomes limitations of conventional pre-intercalation techniques, enabling efficient engineering of MnO2 cathodes for AZIBs.
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