Fast and Reversible Na Intercalation in Nsutite‐Type VO₂ Hierarchitectures

Abstract

Sodium‐ion batteries (SIBs), owing to the natural abundance and low cost of sodium resources, are the promising alternative to lithium‐ion batteries (LIBs) in the field of large‐scale energy storage. Nevertheless, the development of appropriate anodes for SIBs is still a challenge. Vanadium oxides with diverse crystallographic structures and high theoretical capacities hold large opportunities to construct high‐performance SIBs. Among them, new‐state nsutite‐type VO2 (VO2(N)) produced by the random intergrowth of rutile VO2(R) (superior structural stability but sluggish kinetics) and paramontroseite VO2(P) (high electronic/ionic conductivity but weak structural stability) have ample opportunity to obtain desirable sodium storage performance with high capacity, long lifespan, and rapid reaction dynamics. Herein, the spindle‐like VO2(N) is developed through a simple hydrothermal approach. It demonstrates a Na+ (de)intercalation mechanism and exhibits a high capacity of 411 mAh g−1 at 50 mA g−1 as well as outstanding high‐rate cyclic stability (103 mAh g−1 at 10 A g−1 over 6000 cycles). Furthermore, a high‐performance VO2(N)||Na3V2(PO4)2O2F full cell is developed, which shows that the VO2(N) anode has the potential for practical use.

层状钒酸钾应用于高性能高温钠离子电池

“…Because of the abundant sodium element reserves, low price, and similar physicochemical properties to LIBs, sodium-ion batteries (SIBs) have recently been considered as an important potential energy storage device [21][22][23][24][25][26][27][28]. Unfortunately, the relatively high atomic weight (23 g mol −1 , heavier than 6.9 g mol −1 of lithium) and large radius of Na + (1.02 Å, larger than 0.76 Å of lithium) lead to poor rate performance and severe volume expansion during the electrochemical sodiation/desodiation processes [29][30][31][32][33][34][35][36]. Therefore, searching for excellent electrode materials for developing superior SIBs becomes urgent.…”