OXYGEN CONDUCTIVITY AND CHEMICAL DIFFUSION IN PRBA2CU3O6+X

The ionic conductivity with respect to oxygen was studied in PrBa2Cu3O 6+x in the temperature range 600 - 850 degrees C and oxygen pressure r ange 8.1 - 101.3 kPa. The studying method is based on measuring the st eady-state oxygen ion flux through a gas-tight ceramic membrane with a small difference between oxygen pressures in the gas phase at differe nt sides of the sample. The coefficient of the oxygen chemical diffusi on is estimated. The activation energy U of the oxygen conductivity is determined at constant oxygen contents in the sample in the interval 0.35 < x < 0.60. It was found that U = 2.46 - 1.57x (eV) for the tetra gonal phase. The dependence of oxygen conductivity on the stoichiometr y (x) was explained by the interaction of mobile oxygen ions.