The solid solution range and O ion conductivity of Sr/Ca- and Mg-doped NdGaO3 were investigated in Nd1-xMxGa1-yMgyO3, where M was Sr or Ca. The limit of solid solubility in the A sub-lattice was x = 0.1, while the limit for the B sub-lattice was y = 0.15. The conductivity increased, and the activation energy decreased, when only A-sites or only B-sites were doped. However, the conductivity decreased when both A- and B-sites were doped, as compared with single doping. The optimum composition of x = 0 and y = 0.1 gave a maximum conductivity of 0.035S/cm at 800C. The conductivity changed little for O pressures ranging from 1 to about 10-20atm. This indicated that the conductivity of these materials was essentially ionic.

A.Petric, P.Huang: Solid State Ionics, 1996, 92[1-2], 113-7