High temperature dielectric relaxation and energy storage properties achieved in the CaZrO3-SrTiO3 composite ceramics

We synthesized lead-free (1 - x)CaZrO3-xSrTiO(3) solid-solution ceramics and studied their structure, dielectric and energy storage properties. X-ray diffraction and scanning electron microscope reveal the microstructure of the samples. A high temperature dielectric relaxation behavior at the temperature ranges of 200 degrees C-550 degrees C is found for x = 0.3, 0.5 and 0.7 samples. We explore that the origin of high temperature dielectric relaxation behavior is related to the migration of oxygen vacancies by Arrhenius law and oxygen treatment experiment. Moreover, with the increase of SrTiO3 content, the 0.3CaZrO(3)- 0.7SrTiO(3) exhibits high dielectric constant (epsilon = 3645 at 1 kHz), low dielectric loss (tan delta = 0.00081 at 1 kHz), good energy density (W-rec = 1.29 J/cm(3)) and high efficiency (eta = 87.7%) simultaneously, and the possible causes of energy storage behavior dependence are analyzed in detail.