Here, TiO2, MgO, Mo, Al2O3 and Bi2O3 up to a few percentages in quantity were intentionally added to BaZr0.9Y0.1O3−δ. The selected additives did not contribute to any improvement of the sintering behaviour. The lattice parameter of BaZr0.9Y0.1O3−δ for the samples containing additives was smaller than for the pure material. The bulk conductivity also falls drastically with metal addition. For instance, the conductivity of the sample containing TiO2 was 2.5 orders of magnitude lower than the sample without additive. The grain boundary conductivity was also affected by the presence of metal ions.

Effect of Minor Element Addition on the Electrical Properties of BaZr0.9Y0.1O3−δ. S.B.C.Duval, P.Holtappels, U.Stimming, T.Graule: Solid State Ionics, 2008, 179[21-26], 1112-5