Constructing Universal Ionic Sieves via Alignment of Two-Dimensional Covalent Organic Frameworks (COFs).
Cheng Jiang1, Mi Tang1, Shaolong Zhu1
1School of Optical and Electronic Information, Wuhan National Laboratory for Optoelectronics (WNLO), Huazhong University of Science and Technology, Wuhan, 430074, China.
Angewandte Chemie (International Ed. in English)
|October 9, 2018
Summary
Researchers developed novel graphene-supported 2D covalent organic framework (COF) membranes. These membranes effectively suppress the shuttle effect in batteries, enhancing cycle life and performance for sodium-ion and Li-S systems.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- The shuttle effect in batteries causes capacity loss and reduces cycle life.
- Two-dimensional (2D) covalent organic frameworks (COFs) offer potential for ionic sieves to mitigate this effect.
- The insolubility of COFs hinders the creation of ordered membranes.
Purpose of the Study:
- To develop a method for creating ordered 2D COF membranes.
- To inhibit the shuttle effect in battery systems.
- To enhance battery cyclability and performance.
Main Methods:
- Anisotropic ordering of 2D COFs by depositing them onto graphene.
- Fabrication of double-layer membranes.
- Testing membrane performance in organic sodium-ion and Li-S batteries.
Main Results:
- Successfully achieved anisotropic ordering of 2D COFs on graphene.
- The resulting membranes act as effective ionic sieves.
- Demonstrated significant inhibition of the shuttle effect.
Conclusions:
- The novel graphene-supported COF membranes offer a versatile solution for inhibiting the shuttle effect.
- These membranes lead to high cyclability in both organic sodium-ion and Li-S batteries.
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