Enhancing Sodium-Ion Storage Behaviors in TiNb2O7 by Mechanical Ball Milling

• Published in: ACS applied materials & interfaces 2017-03, Vol.9 (10), p.8696-8703
• Main Authors: Huang, Yangyang, Li, Xiang, Luo, Jiahuan, Wang, Kun, Zhang, Qin, Qiu, Yuegang, Sun, Shixiong, Liu, Shantang, Han, Jiantao, Huang, Yunhui
• Format: Article
• Language: English
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.6b15887

Sodium-ion batteries (SIBs) have shown extensive prospects as alternative rechargeable batteries in large-scale energy storage systems, because of the abundance and low cost of sodium. The development of high-performance cathode and anode materials is a big challenge for SIBs. As is well known, TiNb2O7 (TNO) exhibits a high capacity of ∼250 mAh g–1 with excellent capacity retention as a Li-insertion anode for lithium-ion batteries, but it has rarely been discussed as an anode for SIBs. Here, we demonstrate ball-milled TiNb2O7 (BM-TNO) as an SIB anode, which provides an average voltage of ∼0.6 V and a reversible capacity of ∼180 mAh g–1 at a current density of 15 mA g–1, and presents excellent cyclability with 95% capacity retention after 500 cycles at 500 mA g–1. A possible Na storage mechanism in BM-TNO is also proposed.