The O transport in La1-xSrxFe1-yMnyO3-δ, with x = 0 to 0.5 and y = 0.2 or 0.3, was examined by using a thermogravimetric method. When x was less than y, the O transport was found to be very slow whereas the O transport increased by several orders of magnitude when x was greater than y. The O chemical diffusion coefficients were determined for 2 compositions, La0.5Sr0.5Fe0.7Mn0.3O3-δ and La0.6Sr0.4Fe0.8Mn0.2O3-δ, and were found to increase from 1.5 x 10-5 to 5.6 x 10-5cm2/s in La0.5Sr0.5Fe0.7Mn0.3O3-δ and from 1.4 x 10-6 to 1.4 x 10-4cm2/s in La0.6Sr0.4Fe0.8Mn0.2O3-δ at 750 to 1000C. The activation energy for O chemical diffusion was found to be equal to 66kJ/mol for La0.5Sr0.5Fe0.7Mn0.3O3-δ and equal to 136kJ/mol for La0.6Sr0.4Fe0.8Mn0.2O3-δ. The O surface exchange constants varied from 2.5 x 10-4 to 1.8 x 10-2cm/s.

Oxygen Transport in La1-xSrxFe1-yMnyO3-δ Perovskites. L.Mikkelsen, I.G.Krogh Andersen, E.M.Skou: Solid State Ionics, 2002, 152-153, 703-7