Chemical diffusion of oxygen in crushed single-crystal YBa 2Cu 3O 7− δ investigated by thermogravimetry

Abstract

The kinetics of oxygen in- and out-diffusion in the crushed YBa 2Cu 3O 7− δ single-crystal prepared by the top-seeded solution-growth (TSSG) were studied by thermogravimetry. By fitting these experimental curves, the chemical in-diffusion coefficient in the temperature range from 375 to 475 °C were determined as on the order of 10 −10 cm 2/s for the samples with oxygen deficiencies δ < 0.1. The activation energy in the same samples was also determined as 1.04 ± 0.10 eV. The out-diffusion exhibited similar kinetics behavior as in the in-diffusion process at a fixed oxygen partial pressure.