Ultrathin MoS₂ Nanosheets@Metal Organic Framework-Derived N-Doped Carbon Nanowall Arrays as Sodium Ion Battery Anode with Superior Cycling Life and Rate Capability

This study reports the design and fabrication of ultrathin MoS₂ nanosheets@metal organic framework-derived N-doped carbon nanowall array hybrids on flexible carbon cloth (CC@CN@MoS₂) as a free-standing anode for high-performance sodium ion batteries. When evaluated as an anode for sodium ion battery, the as-fabricated CC@CN@MoS₂ electrode exhibits a high capacity (653.9 mA h g⁻¹ of the second cycle and 619.2 mA h g⁻¹ after 100 cycles at 200 mA g⁻¹), excellent rate capability, and long cycling life stability (265 mA h g⁻¹ at 1 A g⁻¹ after 1000 cycles). The excellent electrochemical performance can be attributed to the unique 2D hybrid structures, in which the ultrathin MoS₂ nanosheets with expanded interlayers can provide shortened ion diffusion paths and favorable Na⁺ insertion/extraction space, and the porous N-doped carbon nanowall arrays on flexible carbon cloth are able to improve the conductivity and maintain the structural integrity. Moreover, the N-doping-induced defects also make them favorable for the effective storage of sodium ions, which enables the enhanced capacity and rate performance of MoS₂.