Crumpling Carbon‐Pillared Atomic‐Thin Dichalcogenides and CNTs into Elastic Balls as Superior Anodes for Sodium/Potassium‐Ion Batteries
Xinxin Zhu, Fanjie Xia, Dan Liŭ, Xinyuan Xiang, Jinsong Wu, Jiaheng Lei, Junsheng Li, Deyu Qu, Jinping Liu
Abstract
Abstract With abundant electroactive sites and rapid ion diffusion paths, ultrathin dichalcogenides such as MoS 2 demonstrate enormous potential as anodes for sodium/potassium‐ion batteries (SIBs/PIBs). However, ultrahigh‐aspect‐ratio nanosheets are very easy to aggregate and re‐stack, drastically weakening their intrinsic merits. Here a sustainable dichalcogenide anode is designed via crumpling carbon‐pillared atomic‐thin MoS 2 nanosheets with CNTs into an elastic ball structure (C‐p‐MoS 2 /CNTs). In this architecture, the glucose‐derived carbon pillars atomic‐thin MoS 2 nanosheets and broadens interlayer spacing, ensuring fast Na + /K + diffusion; CNTs act as 3D scaffolds to impede re‐stacking of MoS 2 while providing high‐speed pathways for electrons; the integration of flexible atomic‐thin sheets and high‐toughness CNTs further endows the balls with great elasticity to release the cycling stress. Consequently, the C‐p‐MoS 2 /CNTs material delivers high reversible capacities, outstanding cycling stability, and superior rate performance as anodes for both SIBs and PIBs. Pairing with Na 3 V 2 (PO 4 ) 2 F 3 cathode, the sodium‐ion coin‐cell could operate at a rate up to 50 C at high mass loading of 9.4 mg cm −2 and manifest ultrastable cycling stability at 40 C over 600 cycles. Impressively, the assembled pouch cell can be cycled stably with a high energy density of 188 Wh kg −1 . This study is anticipated to provide inspiration for designing innovative metal dichalcogenides as battery anodes.