Incorporation and conduction of proton in Sr-doped LaMO3 (M=Al, Sc, In, Yb, Y)

In order to clarify the effect of the B site species in ABO3 perovskite oxides on the proton transport properties, the proton incorporation into a series of La0.9Sr0.1MO3-δ, (M = Al, Sc, In, Yb, Y) was studied by measuring the electrical conductivity and electromotive forces of the gas concentration cells, and by a thermogravimetric analysis. The proton concentration and electrical conductivity increased in the order of the B site species, Al < Y=Yb < Sc < In and Al < Y=Yb < In < Sc, respectively. La0.9Sr0.1AlO3-δ showed an oxide ion conductivity, while La0.9Sr0.1YbO3-δ and La0.9Sr0.1YO3-δ exhibited a protonic conductivity in the temperature range of 573–1173 K. La0.9Sr0.1ScO3-δ and La0.9Sr0.1InO3-δ showed a protonic conductivity under 873 K, and a mixed proton and oxide ion conductivity at 1073 K.