Porous lithium titanate nanosheets as an advanced anode material for sodium ion batteries

Abstract

Sodium ion batteries (SIBs) have drawn considerable research attention in energy storage systems due to its low cost and the abundance of sodium resource. However, it is still a big challenge to develop advanced anode materials to achieve high-performance SIBs. In this work, we developed porous lithium titanate (Li4Ti5O12) nanosheets by a simple surfactant-regulating hydrothermal method followed by a calcinating process and used as an anode for SIBs. We investigated the effect of hexadecyl trimethyl ammonium bromide (CTAB) on the morphology and electrochemical properties of Li4Ti5O12 in detail and found that the samples regulated by suitable content of CTAB in the synthesis process have a more regular structure and better electrochemical performance. The optimized sample showed high reversible capacities of 158.9 mAh g−1 and 123.2 mAh g−1 at 0.1 A g−1 and 0.5 A g−1, respectively. The superior electrochemical performance may be originated from the unique porous nanosheet structure, which greatly decreases the charge transfer resistance, shortens the ion diffusion path and offers more active sites for sodium storage.