Electrical properties of polycrystalline TiO2: Equilibration kinetics

Abstract

The equilibration kinetics was determined for high purity polycrystalline TiO2 in the temperature range of 1,123–1,323 K, within a wide range of oxygen activity, $10^{-13}\:\mathrm{Pa}< p(\mathrm{O_2})<75\:\mathrm{kPa}$ . The equilibration kinetics experiments were performed within narrow p(O2) ranges. The obtained kinetic data were used for the determination of the chemical diffusion coefficient, D chem, which exhibits a complex dependence of p(O2). The D chem data are considered in terms of the effect of defect disorder on the mass transport kinetics in the chemical potential gradient. The reported diffusion data may be used for prediction of optimized processing conditions required to impose a homogeneous distribution of oxygen activity within the TiO2 specimen.