Oxygen vacancies at Ni/c-ZrO2 interfaces

The interaction between Ni(001) and cubic-ZrO2(001) surfaces is investigated, focusing on the role of the O vacancies that actually exist in the c-ZrO2 phase stabilized at room temperature. Ab-initio calculations of the electronic charge distribution are performed, allowing full relaxation of the atomic positions. The results indicate a weakening of the Ni–O interactions at the interface, in favour of a change of the Zr–O coordination to adopt configurations closer to the stable low temperature phases.