Oxygen diffusion in YBa2Cu3O7–δ mixed conductors: interpretation of T-jump measurements and experiments on hysteresis of conductivity

Abstract

Oxygen diffusion in YBCO has been investigated by means of non-equilibrium T-jump data. Kinetic curves previously published have been analysed in the temperature range 873–1023 K on the basis of a bipolar transport model leading to the evaluation of the activation energy for oxygen vacancy diffusion. New experimental data on hysteresis cycles of the conductivity, at constant heating rate, are also presented providing further evidence for the oxygen exchange between the oxide and the gas phase.