Hollow Carbon and MXene Dual‐Reinforced MoS2 with Enlarged Interlayers for High‐Rate and High‐Capacity Sodium Storage Systems

Abstract

AbstractSodium‐ion batteries (SIBs) and sodium‐ion capacitors (SICs) are promising candidates for cost‐effective and large‐scale energy storage devices. However, sluggish kinetics and low capacity of traditional anode materials inhibit their practical applications. Herein, a novel design featuring a layer‐expanded MoS2 is presented that dual‐reinforced by hollow N, P‐codoped carbon as the inner supporter and surface groups abundant MXene as the outer supporter, resulting in a cross‐linked robust composite (NPC@MoS2/MXene). The hollow N, P‐codoped carbon effectively prevents agglomeration of MoS2 layers and facilitates shorter distances between the electrolyte and electrode. The conductive MXene outer surface envelops the NPC@MoS2 units inside, creating interconnected channels that enable efficient charge transfer and diffusion, ensuring rapid kinetics and enhanced electrode utilization. It exhibits a high reversible capacity of 453 mAh g−1, remarkable cycling stability, and exceptional rate capability with 54% capacity retention when the current density increases from 100 to 5000 mA g−1 toward SIBs. The kinetic mechanism studies reveal that the NPC@MoS2/MXene demonstrates a pseudocapacitance dominated hybrid sodiation/desodiation process. Coupled with active carbon (AC), the NPC@MoS2/MXene//AC SICs achieve both high energy density of 136 Wh kg−1 at 254 W kg−1 and high‐power density of 5940 W kg−1 at 27 Wh g−1, maintaining excellent stability.