Interfacial redox modulation of polysulfides with ferrocene functionalized separator in Al–S batteries

• Published in: Materials today chemistry Vol. 38; p. 102055
• Main Authors: Zhou, Xiaoyu, Wu, Chuanliang, Zhao, Zelin, Wang, Yusheng, Yang, Yuanyuan, Guo, Jingxing, Wang, Jia, He, Xiaolong, Xiang, Yinyu, Han, Ning, Li, Junsheng
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2024
• Subjects: Aluminum-sulfur battery; Kinetics; Metallocene; Separators; Shuttle effect; Aluminum-sulfur battery; Separators; Kinetics; Metallocene; Shuttle effect
• ISSN: 2468-5194; 2468-5194
• DOI: 10.1016/j.mtchem.2024.102055

Despite the bright future of aluminum-sulfur (Al–S) batteries due to the ultrahigh energy-to-price ratios, the development of this new energy storage system is plagued by the shutting of polysulfides and sluggish kinetics during redox conversions. Herein, ferrocene as efficient polysulfide mediators and electrocatalysts is covalently grafted onto glass fiber (GF) membranes, which serves as separators in Al–S batteries. Attributed to the strong chemisorption and catalytic effect of metallocene toward polysulfide conversions, Al–S cells assembled with the grafted separators deliver an ultrahigh initial capacity of 1347.9 mAh g−1 (at 200 mA g−1) and desirable rate performance (328.1 mAh g−1 at 500 mA g−1). As validated by theoretical calculations, effective polysulfide binding is achieved through beneficial cation-π interactions between Al3+ in polysulfides and the negatively charged cyclopentadienyl ligands in ferrocene, providing novel insights into the exploration of metal-sulfur chemistries for stable energy storage. Configured with FeCp2@GF membrane, the positive effects from both anode and cathode were integrated, which contributed to the enhanced the electrochemical performance of Al–S batteries. This work creates new inspiration for the modification of separators for stabilizing other metal-sulfur batteries. [Display omitted] •A multifunctional FeCp2@GF membrane is fabricated by covalent-grafting method.•The grafted-ferrocene has reached the purpose of “killing two birds with one stone".•Enhanced electrochemical performances are achieved with the FeCp2@GF membrane.