Oxygen exchange in Pr2NiO4+delta, at high temperature and direct formation of Pr4Ni3O10-x

We have studied the stability of Pr2NiO4+delta under pure oxygen flow by in situ measurement of its weight versus T. Above 850 degrees C a fast oxidation is observed corresponding to the ex-solution of PrOy species and to the formation of metallic Pr4Ni3O10-x. This reaction is not reversible. The quantity of exchanged oxygen, its fast kinetics, and the metallic behavior of the composite suggest that this material should have interesting applications for electrodes of solid oxide fuel cells. (C) 2000 Academic Press.