TiO2 Nanotubes Array on Carbon Cloth as a Flexibility Anode for Sodium-Ion Batteries

In this work, three-dimensional (3D) TiO2 nanotubes (NTs) on carbon cloth (CC) (TiO2 NTs/CC) were synthesized by a method involving formation of a ZnO@TiO2 nanorod (NRs) on CC (ZnO@TiO2 NRs/CC) structure and a subsequent chemical etching process for ZnO NRs template. The 3D TiO2 NTs/CC were applied as flexible anodes for sodium ion batteries (SIBs). The TiO2 NTs/CC yielded high specific capacity and good cycling stability, superior to that of some reported TiO2 nanocomposites. The TiO2 NTs/CC delivered a reversible capacity of 260 mA.h.g(-1) and 85.1% capacity retention over 150 cycles at current density of 0.25 C (1 C = 335 mA.g(-1)). It also exhibited high rate capacity of 200 mA.h.g(-1) at 0.5 C. Even at a high rate of 1.0 C, the TiO2 NTs/CC can still maintain a high capacity of 100 mA.h.g(-1). Moreover, it was observed that the electrochemical performance for the TiO2 NTs/CC was much better than that (150 mA.h.g(-1) for up to 150 cycles) of a solid TiO2 NRs/CC counterpart, which also demonstrated the capacity enhancement and good cycling stability.