An SbOx/Reduced Graphene Oxide Composite as a High-Rate Anode Material for Sodium-Ion Batteries

Antimony has attracted enormous attention as anode materials for sodium-ion batteries owing to its high theoretical gravimetric capacity (similar to 660 mA h g(1)). Despite the outstanding gravimetric capacity advantage, antimony suffers from unsatisfactory electrochemical performance originating from its huge volume changes during repeated sodium insertion/extraction. Herein, we synthesize an SbOx/reduced graphene oxide (SbOx/RGO) composite through a wet-milling approach accompanied by redox reaction between Sb and GO. When used as an anode material for sodium-ion batteries, SbOx/RGO exhibits high rate capability and stable cycling performance. A reversible capacity of 352 mA h g(1) was obtained even at a current density of 5 A g(1). More than 95% capacity retention (409 mA h g(1)) was achieved after 100 cycles at a current density of 1 A g(1). The excellent electrochemical performance is due to the SbO bonding between nanometer-sized SbOx particles surface and highly conductive RGO, which can not only effectively prevent SbOx nanoparticles from aggregation upon cycling but also promote the electrons and sodium ions transportation.