Novel antimony phosphate loaded on grid-like N, S-doped carbon for facilitating sodium-ion storage

Abstract

The mesh-like hard carbon loaded SbPO4 (SbPO4/NTC) was harvested and employed as anode material for sodium ion batteries. Profiting from prominent capacitance, porous structure, and sufficient buffering space, the composite realizes high electrochemical kinetics for sodium ion storage. The SbPO4/NTC composite gains impressive battery properties, such as high discharge capacity of 413.7 mAh g−1 under 0.5 A g−1 after 200 cycles and conspicuous rate performance of 365.7 mAh g−1 even at 6 A g−1. In addition, the composite demonstrates a wide operation-temperature window with favorable capacities of 194.3–397.6 mAh g−1 from −10 °C to 60 °C at 0.1 A g−1. The phase transition and sodium storage mechanism are elucidated by density functional theory (DFT) calculation. Therefore, the SbPO4/NTC composite has a great potential for high-efficient sodium ion storage.