Cooperative Oxygen Dynamics in Fuel Cell Materials Gd2Ti2-yZryO7

K.J. Moreno; G. Mendoza-Suárez; A.F. Fuentes; J. García-Barriocanal; C. León; J. Santamaría. Cooperative Oxygen Dynamics in Fuel Cell Materials Gd2Ti2-yZryO7. Physical Review B 71 (2005) 132301. ISSN: 1098-0121. 2005, Vol. 71, p. 132301-1-2005.

We report on dispersive conductivity measurements in the oxygen ion conductor Gd2Ti2−yZryO7. Increasing Zr content leads to higher concentration of oxygen vacancies and results in higher activation energies for long-range ion transport, whilst the microscopic energy barrier for single ion hopping remains constant. We find evidence that, besides oxygen binding energy, enhanced cooperativity in oxygen ion dynamics determines the activation energy for long-range diffusion