Two-Dimensional Covalent Organic Frameworks with Enhanced Aluminum Storage Properties
Hongyan Lu1,2, Fangyi Ning1, Rong Jin1
1Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Key Laboratory of High Performance Polymer Materials and Technology, MOE, Nanjing University, Nanjing, 210023, P.R. China.
Chemsuschem
|May 6, 2020
Summary
Covalent organic frameworks (COFs) enhance aluminum-ion batteries by enabling faster anion diffusion. This leads to improved stability and rate capabilities for advanced energy storage solutions.
Area of Science:
- Materials Science
- Electrochemistry
- Energy Storage
Background:
- Aluminum-ion batteries (AIBs) offer safety and abundance but suffer from slow kinetics due to sluggish chloroaluminate anions.
- Improving the rate capability is crucial for practical AIB applications.
Purpose of the Study:
- To investigate the use of covalent organic frameworks (COFs) as cathode materials in AIBs.
- To enhance the electrochemical performance of AIBs by addressing anion diffusion limitations.
Main Methods:
- Utilized COFs as cathode material in AIBs.
- Conducted theoretical and experimental analyses of COF structure and electrochemical performance.
- Evaluated anion diffusion, intercalation, stability, and rate capability.
Main Results:
- COFs facilitate rapid anion diffusion and intercalation without structural degradation.
- The COF cathode exhibits a high specific surface area (1794 m²/g) and hierarchical pores.
- Achieved remarkable long-term stability with 150 mAh/g after 13,000 cycles at 2 A/g.
- Demonstrated excellent rate capability, retaining 113 mAh/g at 5 A/g.
Conclusions:
- COFs show significant potential as cathode materials for efficient chloroaluminate anion storage in AIBs.
- The robust framework and porous structure of COFs are key to their performance.
- This study highlights COFs for advancing AIB technology and other large-ion storage systems.
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