Electrochemical Properties of Lithium Titanate Synthesized by Reassembly of Nanosheets

The electrochemical properties of titanate nanosheets and layer-structured lithium titanate obtained by restacking of titanate nanosheets were investigated in comparison with those of layer-structured lithium titanate obtained by ion-exchange. Restacked lithium titanate was synthesized by reassembling titanate nanosheets with LiOH aqueous solution. The nanosheets were 50-200 nm wide and 1.7 nm thick. The crystal structure inside the nanosheets was the same as that the of parent material. The oxidation current peaks observed in cyclic voltammograms of titanate nanosheets and restacked material were 1.6 V (Li/Li+), which was lower than that of ion-exchanged material by 0.3 V. The discharge capacity of restacked material was 96 mAh g-1, indicating that 32% of the titanium ions were reduced.