Surface evolution of rutile TiO2 (1 0 0) in an oxidizing environment

Transmission electron microscopy (TEM) has been used to study the rutile TiO2 (1 0 0) surface in an oxidizing environment. By changing annealing conditions, TiO2 surfaces with different morphologies are obtained. We report a new centered (2 × 2) surface reconstruction on this surface. Our experimental data indicates that this is a meta-stable, oxygen deficient structure formed as the disordered surface regains its stoichiometry in an oxidizing annealing environment.