Effective chemical diffusivities in the proton conductor, SrZr0.95Yb0.05O3, were determined by using electrochemical techniques. A proton concentration gradient was established by using the Hebb-Wagner technique, and the evolution with time of the voltage across the electrolyte was monitored. At temperatures of between 300 and 600C, it was found that the proton diffusivities could be described by:

D (cm2/s) = 0.0137 exp[-0.58(eV)/kT]

T.Schober, J.Friedrich, J.B.Condon: Solid State Ionics, 1995, 77[1], 175-9