Electric field induced texture in titania during experiments related to flash sintering

We show that (1 1 0) and (1 1 1) peaks weaken while the (2 1 1) X-ray diffraction peak gains in intensity in titanium dioxide under the influence of the electric field, during in-situ experiments of flash sintering, carried out at the Advanced Photon Source (APS). The effect is reversible, appearing and vanishing when the field is turned on and off. The changes in the peak intensities are immediate, but they fluctuate with time even though the electric field remains constant. Similar experiments with 3 mol% yttria stabilized zirconia have shown time dependent emergence of new peaks signaling the formation of a different phase, apparently by a diffusion controlled process. In contrast, in titania the existing peaks change intensity under the electric field. We attribute the events in titania to short range movement of atoms and defects in the lattice.