Dielectric properties of valence compensated Ca1−xBixTi1−xCrxO3 perovskite prepared using the sol-gel process

Ca1−xBixNb1−xCrxO3 (x=0.01-0.5) ceramic powders were synthesized using the sol-gel process. The single-phase solids can be presented at x=0.01 and 0.03. The coexistence of orthorhombic perovskite and the secondary phase of BiCrO3 was verified, as presented for x=0.05-0.5. Grains with a micro-cube topography were obtained for x=0.3-0.5. The average grain size is about 0.4 and 1.1 μm for x=0.3 and 0.5, respectively. The highest dielectric constant peak was measured at around 55 °C for x=0.5 and at 75 °C for x=0.3. The high dielectric constant was caused by the formation of barrier layers at the interface of the bi-phase mixed ceramics. Space charge polarization contributed to the observed behavior.