Effect of Chemical Lithium Insertion into Rutile TiO2 Nanorods

Abstract

Rutile TiO2 nanorods were synthesized by hydrolysis of TiCl4 followed by a hydrothermal method. Lithium insertion into the rutile nanorods was achieved by a chemical lithium insertion process. The structural evolution of nanostructured rutile upon lithium insertion was characterized by several experimental techniques, namely, XRD, TEM, SAED and 6Li MAS NMR. The XRD and TEM studies indicate the formation of lithium titanate phase (LixTiO2) during lithium insertion. Additionally, SAED patterns show that the lithium titanate phase has cubic symmetry. Finally, high magnetic field (21.1 T) 6Li MAS NMR reveals that the lithium titanate phase adopts two different structures depending on lithium content. Taken together, the four techniques consistently show that the insertion of lithium into rutile TiO2 nanorods causes two consecutive structural phase transformations to lithium titanate phases with spinel (Fd3m) and rocksalt (Fm3m) structures at x = 0.46 and 0.88, respectively. In addition, the broad line width...