Template-Free Construction of Self-Supported Sb Prisms with Stable Sodium Storage

Antimony (Sb) is a promising anode material for sodium-ion batteries owing to its large capacity of 660 mAh g(-1). However, its practical application is restricted by the rapid capacity decay resulted from a large volume expansion up to 390% upon Na alloying. Herein, construction of a self-supported Sb array that has enough space allowing for effective accommodation of the volume change is reported. The array of Sb prisms is directly grown on a Cu substrate via a template-free electrodeposition, followed by mild heating to consolidate the structural integrity between Sb and Cu. The resulting 3D architecture endows the Sb array with excellent sodium storage performance, exhibiting a reversible capacity of 578 mAh g(-1) and retaining 531 mAh g(-1) over 100 cycles at 0.5 C. The potential of Sb array in sodium-ion full cells by pairing it with a Na-0.67(Ni0.23Mg0.1Mn0.67)O-2 cathode is further demonstrated. This full cell affords a specific energy of 197 Wh kg(-1) at 0.2 C and a specific power of 1280 W kg(-1) at 5 C. Considering its low cost and scale-up capability, the template-free route may find extensive applications in designing electrode architectures.