Abstract: The invention relates to a mixed oxide material with a high electron conductivity of empirical formula ABOY, where y≠3 and where A comprises at least one metal selected from Na, K, Rb, Ca, Ba, La, Pr, Sr, Ce, Nb, Pb, Nd, Sm and Gd, and B comprises at least one metal selected from the group consisting of Cu, Mg, Ti, V, Cr, Mn, Fe, Co, Nb, Mo, W and Zr, where A and B cannot both be Nb and where the compound SrVO2.5 is excluded. The material may be a perovskite-type material, in which y=3−&dgr; and &dgr;≠0, with values for &dgr; in the range from approximately −0.2 to approximately, −0.05 or in the range from +0.05 to +0.7. The material may also be a Brown-Millerite-type material, for which y=2.5−&xgr; and &xgr; has a value in the range from approximately −0.2 to approximately −0.05 or in the range from +0.05 to approximately 0.3.