Invité par Nick Barrett,
Abstract :
The adsorption and dissociation of water on BaTiO3 (001) surfaces has been studied by density- functional calculations. It is found that such surfaces are strongly reactive with respect to water so that, in ambient conditions, they are probably fully hydroxylated. A state of molecular adsorption is found, distinct from simple physisorption, as already observed on some other perovskite surfaces such as SrZrO3 and SrTiO3. It is shown how the direction of the in-plane polarization and the adsorption might influence each other, leading to some surface imprint effect due to water. The results of related experiments are discussed, as well as the implications of such results on the screening mechanisms at ferroelectric surfaces.
CEA, DAM, DIF, F-91297 Arpajon, France