(Yb1−xCax)2Ti2O7 and (Yb1−xBax)2Ti2O7 (x = 0, 0.05, 0.1) were synthesized using hydroxide coprecipitation and mechanical activation of oxide mixtures, and their electrical conductivity was measured from 350 to 1000C. The pyrochlore titanate (Yb0.9Ca0.1)2Ti2O7 synthesized at 1400C from a mechanically activated oxide mixture had the highest conductivity, about 0.1S/cm at 1000C, among the O-ion conducting pyrochlores so far studied. The (Yb0.95Ca0.05)2Ti2O7 and (Yb0.9Ca0.1)2Ti2O7 samples prepared by reacting coprecipitated powder mixtures at 1400C had a lower conductivity, as did (Yb1−xBax)2Ti2O7 (x = 0.05, 0.1) samples prepared using mechanical activation.

Effect of Heterovalent Substitution on the Electrical Conductivity of (Yb1−xMx)2Ti2O7 (M = Ca, Ba; x = 0, 0.05, 0.1). A.V.Shlyakhtina, I.V.Kolbanev, O.K.Karyagina, L.G.Shcherbakova: Inorganic Materials, 2006, 42[5], 528-31