Crumpling Carbon‐Pillared Atomic‐Thin Dichalcogenides and CNTs into Elastic Balls as Superior Anodes for Sodium/Potassium‐Ion Batteries

Abstract

AbstractWith abundant electroactive sites and rapid ion diffusion paths, ultrathin dichalcogenides such as MoS2 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 MoS2 nanosheets with CNTs into an elastic ball structure (C‐p‐MoS2/CNTs). In this architecture, the glucose‐derived carbon pillars atomic‐thin MoS2 nanosheets and broadens interlayer spacing, ensuring fast Na+/K+ diffusion; CNTs act as 3D scaffolds to impede re‐stacking of MoS2 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‐MoS2/CNTs material delivers high reversible capacities, outstanding cycling stability, and superior rate performance as anodes for both SIBs and PIBs. Pairing with Na3V2(PO4)2F3 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.