Heteroleptic Coordination Polymer Electrolytes Initiated by Lewis-Acidic Eutectics for Solid Zinc–Metal Batteries
2022; American Chemical Society; Volume: 34; Issue: 19 Linguagem: Inglês
10.1021/acs.chemmater.2c02417
ISSN1520-5002
AutoresGuoli Lu, Huayu Qiu, Xiaofan Du, Keval K. Sonigara, Jinzhi Wang, Yaojian Zhang, Zheng Chen, Lin Chen, Yongwen Ren, Zhiming Zhao, Junzhe Du, Suying Li, Jingwen Zhao, Guanglei Cui,
Tópico(s)Conducting polymers and applications
ResumoSolid polymer electrolytes (SPEs) offer a viable path for overcoming the interfacial problems caused by side reactions and irregular deposition in rechargeable Zn (zinc)–metal batteries. However, this potential has been hampered by limited Zn2+ mobility in polymers; a central conundrum remains on how to solvate Zn2+ strongly enough to free it from anionic traps but weakly enough to minimize its migration barriers. Inspired by biologically dynamic Zn functions, we report a general strategy for constructing highly Zn2+-conductive SPEs by the engineering of heteroleptic coordination. Leveraging polymerization catalyzed by Lewis-acidic Zn2+ predissociated eutectics, we stoichiometrically integrate polymeric ligands (polyacrylamide) with kindred small-molecule co-ligands (acetamide) for Zn2+ centers. This heteroleptic configuration allows for the formation of entropy-increased ion channels with both labile Zn2+–polymer bonding and accelerated polymer mobility, warranting conductivity gains of 2 orders of magnitude and doubling the Zn2+-transference number to 0.44, compared with traditional SPEs. The applicability of the proposed heteroleptic coordination design is also demonstrated by the improved reversibility of Zn plating/stripping process (1200 h) and prolonged cycle life of solid Zn–metal batteries (350 cycles with Mo6S8 cathodes) with improved Coulombic efficiency (∼99%). This study underscores the importance of tailoring the coordination environment in improving cationic mobility in polymers.
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