Effect of coalesce doping of Li and Bi on structural, optical and dielectric properties of TCO anatase TiO2 nanoparticles

Abstract

Anatase (TiO2) ceramic nanoparticle (NPs) powder doped with Bi/Li ions was synthesized by a facial precipitation method. The structural, optical, and electrical properties of the NP powders were studied by X‐ray diffraction, diffuse reflection spectroscopy (DRS), and the AC dielectric measurements. It was concluded that it is possible to construct a core/shell structure in TiO2 ceramic by doping with Bi ions. Thus, the dielectric measurements show the creation of colossal permittivity (CP) of magnitude ε' ∼103 in the frequency range: 1  ≤   f  ≤ 100 kHz. The CP results were explained within the framework of the core/shell model and doping mechanisms. It was found the present CP phenomenon can be switched off by Li co-doping, which was explained within the framework of doping mechanisms.