Determination of the ionic transport numbers of lanthanum gallate materials by impedance spectroscopy and modified EMF method

A combination of impedance spectroscopy and a modified electromotive force method (emf) were used to evaluate the ionic transport numbers and the overall conductivity of several doped lanthanum gallate materials, i.e. La(0.9)Sr(0.1)Ga(1-x)Mg(x)O(3-delta) (x=0.05-0.30), La(0.9)A(0.1)Ga(0.8)Mg(0.2)O(3-delta) (A=Sr, Ba and Ca) and La(0.9)Sr(0.1)Ga(0.8)Mg(0.2)Co(y)O(3-delta) (y=0.015 and 0.045). La(0.9)Sr(0.1)Ga(0.8)Mg(0.2)O(2.85) (LSGM) sample showed the maximum ionic transport number in the temperature range 900-1173 K, around 0.99 in bot O(2)/air and H(2)/ air gradients.