Incorporation and conduction of proton in Sr-doped LaMO sub(3) (M=Al, Sc, In, Yb, Y)

In order to clarify the effect of the B site species in ABO sub(3) perovskite oxides on the proton transport properties, the proton incorporation into a series of La sub(0.9)Sr sub(0.1)MO sub(3- delta ), (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. La sub(0.9)Sr sub(0.1)AlO sub(3- delta ) showed an oxide ion conductivity, while La sub(0.9)Sr sub(0.1)YbO sub(3- delta ) and La sub(0.9)Sr sub(0.1)YO sub(3- delta ) exhibited a protonic conductivity in the temperature range of 573-1173 K. La sub(0.9)Sr sub(0.1)ScO sub(3- delta ) and La sub(0.9)Sr sub(0.1)InO sub(3- delta ) showed a protonic conductivity under 873 K, and a mixed proton and oxide ion conductivity at 1073 K.