It was recalled that the response time of this high-temperature resistive O sensor material depended upon the bulk O diffusivity and surface exchange processes. Here, the diffusivity of 18O was investigated in La-doped monocrystals, at temperatures ranging from 700 to 900C, by using secondary ion mass spectrometry. Tracer diffusivities of between 2 x 10-15 and 10-13cm2/s were deduced from the secondary ion mass spectrometry results.

U.Kiessling, J.Claus, G.Borchardt, S.Weber, S.Scherrer: Journal of the American Ceramic Society, 1994, 77[8], 2188-90