In situ structural changes upon electrochemical lithium insertion in nanosized anatase TiO2

Abstract

The intercalation of lithium in nanosized TiO2 has been studied for its application as an electrode for rechargeable Li-ion batteries. In this paper, we use a synthesis process in order to obtain a low-density anatase TiO2 presenting monocrystalline particles of 7-8 nm. These textural characteristics allow this material to host almost twice as much Li (300 mAh· g-1) than that of a micrometer sized anatase. In this study, in situ X-ray absorption spectroscopy is used to monitor and understand the structural changes that happen upon lithium insertion/removal, leading to a reversible two-phase transition process: TiO2 (I41/amd) → Li-titanate (Imma) → Li1TiO2 (I4 1/amd). © 2010 American Chemical Society.