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Title: Maleimide-functionalized metal–organic framework for polysulfide tethering in lithium–sulfur batteries
Lithium–sulfur (Li–S) batteries have great potential as next generation energy storage devices. However, the redox chemistry mechanism involves the generation of solubilized lithium polysulfides, which can lead to leaching of the active material and, consequently, passivated electrodes and diminished capacities. Chemical tethering of lithium polysulfides to materials in the sulfur cathode is a promising approach for resolving this issue in Li–S batteries. Borrowing from the field of synthetic chemistry, we utilize maleimide functional groups in a Zr-based metal–organic framework to chemically interact with polysulfides through the Michael Addition reaction. A combination of molecular and solid-state spectroscopies confirms covalent attachment of Li 2 S x to the maleimide functionality. When integrated into Li–S cathodes, the maleimide-functionalized framework exhibits notable performance enhancements over that of the unfunctionalized material, revealing the promise of polysulfide anchors for Li–S battery cycling.  more » « less
Award ID(s):
1945114
NSF-PAR ID:
10310159
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Materials Advances
Volume:
2
Issue:
9
ISSN:
2633-5409
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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