Published online by Cambridge University Press: 01 February 2011
In order to stabilize the fast oxide ion conducting properties of the high temperature form of Ba2In2O5 at lower temperature, oxygen rich doped Ba2In2O5+δ brownmillerite were prepared by partial substitution of Ba and In with higher valence cation. Vanadium, niobium, tantalum, molybdenum and tungsten were introduced on indium site and bismuth on barium site. Solid solutions were evidenced in all the cases. They were characterized by high temperature X-ray diffraction and impedance spectroscopy. A neutron diffraction study was carried out and allowed to extract preferential oxygen pathways in these materials.