Materials of the form, Ln2−xCaxNiO4+δ (with Ln = La, Pr, Nd), were and characterized by using various techniques. These oxides exhibited a high electronic conductivity (about 100S/cm at 700C) as well as high values of O diffusion and surface exchange coefficients (determined using secondary ion mass spectrometric analysis of the 18O isotope). The O diffusion values of Pr2NiO4+δ were the highest among the compounds studied. In the Nd-series, they were slightly improved by the creation of Nd vacancies, while they were affected by the replacement of Nd by Ca.

Oxygen Diffusion and Transport Properties in Non-Stoichiometric Ln2−xNiO4+δ Oxides. E.Boehm, J.M.Bassat, P.Dordor, F.Mauvy, J.C.Grenier, P.Stevens: Solid State Ionics, 2005, 176[37-38], 2717-25