Penne‐Like MoS2/Carbon Nanocomposite as Anode for Sodium‐Ion‐Based Dual‐Ion Battery

: The dual-ion battery (DIB) system has attracted great attention owing to its merits of low cost, high energy, and environmental friendliness. However, the DIBs based on sodium-ion electrolytes are seldom reported due to the lack of appropriate anode materials for reversible Na+ insertion/extraction. Herein, a new sodium-ion based DIB named as MoS2 /C-G DIB using penne-like MoS2 /C nanotube as anode and expanded graphite as cathode is constructed and optimized for the first time. The hierarchical MoS2 /C nanotube provides expanded (002) interlayer spacing of 2H-MoS2 , which facilitates fast Na+ insertion/extraction reaction kinetics, thus contributing to improved DIB performance. The MoS2 /C-G DIB delivers a reversible capacity of 65 mA h g-1 at 2 C in the voltage window of 1.0-4.0 V, with good cycling performance for 200 cycles and 85% capacity retention, indicating the feasibility of potential applications for sodium-ion based DIBs.