Sb₂O₄@rGO Nanocomposite Anode\nfor High Performance Sodium-Ion Batteries

Abstract

Research\non high performance electrode materials is significant\nfor further development of sodium ion batteries (NIBs). The Sb₂O₄ anode can be employed as a promising anode material\nfor NIBs owing to its high theoretical capacity of 1227 mAh·g^–1. In this paper, we report the Sb₂O₄@rGO nanocomposite anode for NIBs which exhibit good cyclability\nand rate capability due to the formation of wrinkled rGO nanosheets\nduring cycling. Well-formed nanowrinkles act as a template for anchoring\nSb₂O₄ particles during cycling and effectively\nalleviate the strain due to the volume expansion. The improved electrochemical\nperformance is attributed to the shorter Na⁺ ion diffusion\npath length from the small nanoparticles and good electrons as well\nas ion transport from the intimate contact between the active Sb₂O₄ particles and rGO matrix. At a current density\nof 0.1 A·g^–1, it retains the 94.2% (890 mAh·g^–1) of initial reversible capacity after 100 cycles.\nOver prolonged cycling (after 500 cycles), the Sb₂O₄@rGO electrode still delivers a reversible capacity of 626\nmAh·g^–1 at a current density of 0.6 A·g^–1. These significant results offer hope for the exploration\nof making high capacity anodes combined with a reduced graphene oxide\nmatrix to alleviate the strain during cycling.