NaCl-pinned Antimony Nanoparticles Combined with Ion-Shuttle-induced Graphitized 3D Carbon to Boost Sodium Storage

Abundant sodium resources provide compelling competitive advantage for sodium-ion battery (SIBs) applications. Correspondingly, it is urgently required to develop high-performance and low-cost anode materials for SIBs. Here, we report a composite of antimony nanoparticles anchored on N/S co-doped 3D carbon for superior SIB anodes. During the synthesis, NaCl exerts a “pinning effect” to restrict the growth of antimony in the carbon matrix and results in nano-sized antimony particles. Given the enhanced-charge/ion-transfer kinetics ensured by nano-Sb and the structural advantages derived from the N/S co-doped 3D porous carbon, which not only remain robust upon cycling but also undergo graphitization by the ion shuttle effect to stimulate a stronger electrochemical response during the activation process, this composite maintains a 98.9% capacity ratio over 20,000 cycles at 10 A g-1. Furthermore, molecular dynamics simulations reveal that the degree of graphitization has a linear relationship with the ionic radius.