Facile synthesis of nanosized Li4Ti5O12 in supercritical water

Abstract

The high rate capability of lithium titanate (Li4Ti5O12, LTO) is prepared using supercritical hydrothermal synthesis (SHS). The particle size, morphology, crystalline structure and electrochemical properties are analyzed and compared to the properties of LTO particles prepared using a typical solid-state method (SS). Nanosized LTO particles having a high crystallinity are produced in a very short reaction time (15 min) and with subsequent calcination at a low temperature (700 degrees C) or it can be produced in 6h without calcination. The size of SI IS particles is much smaller (20-200 nm, BET surface area of 10-38 m(2) g(-1)) than that of the SS particles (micron size, BET surface area of 5.4 m(2) g(-1)). The SHS LTO particles are highly phase-pure while the SS particles have impurity phases such as anatase TiO2, rutile TiO2 and Li2TiO3. The SHS LTO show higher initial discharge capacity (212 mAhg(-1)) and better cycling stability compared to those of the SS LTO particles (149 mAhg(-1)). Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.