Composites of SnSb Nanoparticles Embedded in Porous Carbon Nanofibers Wrapped with Reduced Graphene Oxide for Sodium Storage

Alloying-type anode materials are hopeful candidates for sodium (Na)-ion batteries (SIBs) because of their high theoretical capacity by forming Na-rich intermetallic compounds. However, the huge volume changes lead to serious aggregation and crushing of active materials during the cycling process, resulting in a rapid decay in the capacity of the electrode materials. Herein, we report the manufacture of reduced graphene oxide wrapped on the surface of tin–antimony/nitrogen-doped porous carbon nanofibers (SnSb/N-PCNFs/rGO) by a coaxial electrospinning technique and subsequent annealing treatment. The cooperative effect of rGO and PCNFs can greatly relieve the volume expansion of the SnSb alloy in the cycling process and offer more insertion sites for Na+ ions, thus significantly improving the electrochemical performance. As a SIB anode, the SnSb/N-PCNFs/rGO composite exhibits better reversible capacity (maintaining 416 mAh g–1 at 100 mA g–1 after 120 cycles), excellent rate performance, and marvelous cycle performance (up to 303 mAh g–1 at 2000 mA g–1 after 1000 cycles), making it a hopeful anode candidate for SIBs.