  Herein, titania thin films are fabricated by a facile liquid-phase method
based on vacuum filtration of a colloidal suspension of titania nanosheets,
which is followed by thermal annealing to transform the nanosheet film into
anatase TiO2. Nanosheet-derived titania thin films exhibit poor resistive
switching with an interface-type mechanism. This behaviour is distinct from the
filamentary switching that has been observed with titania thin films fabricated
by other conventional techniques. This tolerance against conducting-filament
formation may be ascribed to a low concentration of oxygen vacancies in
nanosheet-derived films, which is expected because of the O/Ti ratio of titania
(Ti0.87O2) nanosheets being larger than that of TiO2. Besides, the dielectric
breakdown strength of nanosheet-derived films is found to be comparable to or
higher than that of titania thin films fabricated by other techniques. These
findings clearly indicate the usefulness of nanosheet-derived titania thin
films for dielectric applications.
