Lithium Insertion in Micrometer Sized Rutile TiO2 at Room Temperature: Facilitated by Crystal Chemical Substitution

Abstract

Lithium insertion in micrometer sized rutile TiO2 is reinvestigated. It is known that only negligible amount of lithium can be inserted in micrometer sized rutile TiO2 at room temperature (∼0.06 Li/TiO2). In our previous studies, we have shown that, by reducing the crystallite size of rutile TiO2 to nanometer regime, 1.0 Li/TiO2 can be inserted at room temperature. In another approach, we show here that, by partial crystal chemical substitution of lithium and niobium in place of Ti in micrometer sized rutile TiO2, it is possible to insert lithium even in micrometer regime at room temperature. The ‘lattice lithium’ provides additional diffusion pathways facilitating lithium insertion.