Absorption and Desorption of Oxygen in Y₁Ba₂Cu₃O_7-δ

Abstract

The absorption and desorption velocities of oxygen in a Y 1 Ba 2 Cu 3 O 7-δ sintered sample were measured by a thermogravimetric analysis when the atmospheric gas of nitrogen was exchanged for oxygen and oxygen for nitrogen. The weight change of the sample could be expressed by an exponential function of time in each process. In the absorption process of oxygen, the time constant was a complex function of the temperature, while in the desorption process, it was the monotonous temperature dependence. The diffusion constant and the activation energy were estimated at the temperature range of the tetragonal phase.