Surface self-diffusivity of TiO2 under high-pressure gas

The surface diffusion coefficient of TiO2 under a high-pressure gas of 100 MPa was estimated by using simulation of a sintering model consisting of surface and volume diffusion. The value of the volume diffusion coefficient of TiO2 estimated using the present simulation is similar to the value of the diffusion coefficient of oxygen in TiO2. The surface diffusivity was considered independently of the inert gas atmosphere. The present work, however, shows that the value of the surface diffusion coefficient of TiO2 under a high-pressure argon gas of 100 MPa is about 30 times higher than that under 1 atm.