The effect of CaCO3-doping on the structural and dielectric properties of TiO2

The utilization of CaCO₃ as a dopant to TiO₂ is studied and its effects are compared to those of Al₂O₃ and Li₂CO₃. The dielectric properties of the system have been exploited in the frequency range 1 MHz-1 GHz in order to obtain permittivity data of materials having high-κ´ and low loss. The X-Ray Diffraction technique was employed for the evaluation of the anatase-to-rutile (A-R) phase transition in TiO₂ nanoparticles during calcination. It is found that CaCO₃ doping in TiO₂ increases the anatase-to-rutile transition rate once the phase transformation has been initiated. This behaviour is similar to that of Al₂O₃ and different to the one of Li₂CO₃, where phase transformation occurs at significantly lower temperatures. The formation of the complex oxide CaTiO₃ is also recorded.