2, Argonne National Laboratory, Chicago, Illinois, United States
Titania has been used for photocatalytic reactions, antibacterial activity, die-sensitized solar cell, sensors, self-cleansing usages. The above properties of titania can be further tailored by doping it with other cations such as Sn, Fe and Zr. Sol-gel techniques are most common in preparing the doped powder beyond equilibrium limits but have limited application in the fabrication of bulk materials due to phase separation at high temperature. We have employed flash sintering as a technique to synthesize bulk titania doped with Fe2O3 and ZrO2 to an extent higher than thermodynamically allowed. We use in-situ Energy Dispersive X-ray diffraction to understand the kinetics of doping and sintering in one step. Enhanced diffusion during flash sintering allows TiO2 to be doped to a higher limit and then quickly quenched. Afterwards, we use XPS and Raman Spectroscopy to understand the change in the bonding environment. Impedance analysis shows the change in the conduction behavior and through our collaboration, we hope to determine its use for sensor applications.