Amorphous Mesoporous Titania with High Surface Area for High-Capacity Lithium Storage

Abstract

The Li storage in mesoporous titania was investigated with varying the framework and porous structure by changing the calcination temperature. By the calcination at 673 K, the amorphous framework was converted into anatase, which is accompanied with the lost of angle X-ray diffraction peak around 2θ=2.4° and with an increase of mesopore diameter. The crystallite size increased while the specific surface area decreased with the increase of calcination temperature. The amorphous framework structure was further analysed by Raman spectroscopy and transmission microscopy. The charge-discharge curves were measured for all mesoporous titanias analysed. The maximum capacity was 225 mAh g−1, which was recorded for 773 K-calcined mesoporous titania. The distinct plateaux appeared in mesoporous anatase and the voltage gap between the plateaux in charge and discharge processes decreased with the calcination temperature. The electrochemical behavior was discussed in relation with the meso- and microscopic structures of the material.