Carbon-enhanced centrifugally-spun SnSb/carbon microfiber composite as advanced anode material for sodium-ion battery.

Antimony tin (SnSb) based materials have become increasingly attractive as a potential anode material for sodium-ion batteries (SIBs) owing to their prominent merit of high capacity. However, cyclic stability and rate capability of SnSb anodes are currently hindered by their large volume change during repeated cycling, which results in severe capacity fading. Herein, we introduce carbon-coated centrifugally-spun SnSb@carbon microfiber (CMF) composites as high-performance anodes for SIBs that can maintain their structural stability during repeated charge-discharge cycles. The centrifugal spinning method was performed to fabricate SnSb@CMFs due to its high speed, low cost, and large-scale fabrication features. More importantly, extra carbon coating by chemical vapor deposition (CVD) has been demonstrated as an effective method to improve the capacity retention and Coulombic efficiency of the SnSb@CMF anode. Electrochemical test results indicated that the as-prepared SnSb@CMF@C anode could deliver a large reversible capacity of 798 mA h∙g at the 20th cycle as well as a high capacity retention of 86.8% and excellent Coulombic efficiency of 98.1% at the 100th cycle. It is, therefore, demonstrated that SnSb@CMF@C composite is a promising anode material candidate for future high-performance SIBs.