Ultrathin Li4Ti5O12 Nanosheets as Anode Materials for Lithium and Sodium Storage

Ultrathin Li4Ti5O12 (LTO) nanosheets with ordered microstructures were prepared via a polyether-assisted hydrothermal process. Pluronic P123, a polyether, can impede the growth of Li2TiO3 in the precursor and also act as a structure directing agent to facilitate the (Li1.81H0.19)Ti2O5-2H(2)O precursor to form the LTO nanosheets with the ordered microstructure. Moreover, the addition of P123 can suppress the stacking of LTO nanosheets during calcining of the precursor, and the thickness of the nanosheets can be controlled to be about 4 nm. The microstructure of the as-prepared ultrathin and ordered nano sheets is helpful for Li+ or Na+ diffusion and charge transfer through the particles. Therefore, the ultrathin P123-assisted LTO (P-LTO) nanosheets show a rate capability much higher than that of the LTO sample without P123 in a Li battery with over 130 mAh g(-1) of capacity remaining at the 64C rate. For intercalation of larger size Na+ ions, the P-LTO still exhibits a capacity of 115 mAh g(-1) at a current rate of 10 C and a capacity retention of 96% after 400 cycles.