Freestanding MXene‐Scaffolded Film Cathodes Enable High‐Performance Flexible Zinc‐Ion Batteries

• Published in: Advanced functional materials Vol. 34; no. 36
• Main Authors: Zeng, Zhen, Shen, Jianyu, Lai, Yiliang, Hua, Guoxin, Wang, Yuxiao, Liu, Junyang, Tang, Weihua
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.09.2024
• Subjects: Cathodes; Charge density; Chemical bonds; Cutting equipment; Cutting wear; Electrical resistivity; film electrode; Flexibility; Flexible components; flexible energy storage; Flux density; Folding; freestanding cathode; Manganese dioxide; MXene; MXenes; Single wall carbon nanotubes; Stability; Thin films; Zinc; zinc‐ion battery
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202401059

Flexible electronics are among the highest‐profile devices in today's world. The development of high‐capacity power supply with both flexibility and rate stability is in great demand yet remains highly challenging. Herein, for the first time the construction of freestanding films is reported by integrating α‐MnO2 nanofibers in MXene (Ti3C2Tx) bonded single‐walled carbon nanotubes (SWCNTs) networks (named MXSC) through covalent bonding as binder‐free cathodes for high capacity and rate stability aqueous zinc‐ion battery. The film electrodes boast high electrical conductivity and decent flexibility for rolling and folding. The optimal MnO2@MXSC (α‐MnO2/SWCNTs/MXene = 10:40:60 by weight ratio) cathode contributes a steady specific capacity of 368 mAh g−1 at 1 A g−1 over 1000 cycles charge and discharge process, delivering a high energy density of 354 Wh kg−1 at a power density of 963 W kg−1. More importantly, the MnO2@MXSC cathode demonstrates exceptional cyclic performance after being bent 1000 times. The flexible Zn‐MnO2@MXSC thin film battery maintains its energy storage capability when subject to folding and cutting. Such outstanding abilities of this highly flexible rechargeable MnO2@MXSC cathode offer a unique perspective on powering wearable electronic devices. A freestanding film cathode design without binder and conductive agent enables high‐capacity rate stable flexible zinc‐ion battery. Aqueous ZIBs boast 368 mAh g−1 at 1 A g−1 upon continuous galvanostatic discharge/charge cycling up to 1000 cycles. The film battery maintains stable energy storage subject to bending, twisting and cutting. The hierarchical cathode shows great potential for flexible electronics.