Investigation of local structure and phase transformation in Ce-doped barium titanate and correlation with electrical properties

BaTiO3-based materials are used as the replacement for lead-based perovskite materials for its wide dielectric applications. But the substitution of different doping elements in pure BaTiO3 drastically affects the microstructure, phase transition behavior and electrical properties. In the present work, local structure, phase transformation and dielectric behavior of BaCexTi1-xO3 (BCT) ceramics were studied for compositions x = 0.02, 0.05 and 0.1. A diffuse phase transition from orthorhombic to cubic via tetragonal in BCT with increasing Ce content was observed. An increase in particle size with Ce doping concentration was observed in FESEM images. Spherical and cuboid-shaped particle in the order of 80-150 nm was observed in transmission electron microscopic (TEM) images. RAMAN spectra confirm the tetragonal to cubic phase transition. Local structural and phase transformation behavior was obtained from laboratory-based PDF and XRD, respectively. Change in PDF was observed due to an increase in Ce doping. Dielectric properties decreased for Ce mole fraction of x = 0.1.