Solid State Synthesis of Extra Phase-Pure Li4Ti5O12 Spinel

Abstract

Extra phase-pure Li4Ti5O12 spinel with particle sizes less than 500 nm was synthesized by solid state reaction of mechanochemicaly activated mixture of nano anatase and Li2CO3 for a very short annealing time, 4 h at 800 degrees C. Structural and microstructural properties, the mechanism of solid state reaction between anatase and Li2CO3 as well as thermal stability of prepared spinel were investigated using XRPD, SEM and TG/DSC analysis. The mechanism of reaction implies decomposition of Li2CO3 below 250 degrees C, formation of monoclinic Li2TiO3 as intermediate product between 400 and 600 degrees C and its transformation to Li4Ti5O12 between 600-800 degrees C. The spinel structure is stable up to 1000 degrees C when it is decomposed due to Li2O evaporation.