In situ synthesis of self-standing SbBi-porous carbon fibers enabling ultra-stable sodium-ion storage

Abstract

In this work, we developed an in situ synthesis strategy to grow nanoscale SbBi alloy structures within a porous carbon fiber matrix (SbBi-PCF), yielding a self-standing SbBi-PCF composite anode with exceptional structural stability. Benefiting from the inherently high Na-storage capability of the SbBi alloy, the SbBi-PCF electrode delivers a high specific capacity of ∼259.8 mAh g⁻¹ at 0.1 A g⁻¹. Remarkably, the self-standing SbBi-PCF anode achieves a record-breaking cycling stability with a capacity retention of ∼81.4% after 40 000 cycles, surpassing all previously reported alloy-based anode materials for SIBs.