Excellent dielectric properties and enhanced temperature stability of CaZrO3-modified BaTiO3 ceramic capacitors

x wt% CaZrO3–BaTiO3 (x is the wt% of CaZrO3) was synthesized by a two-step preparation process, using the sol–gel method followed by precipitation. The effect of CaZrO3 content on the ceramic composition, structure, and dielectric performances was systematically investigated. The X-ray diffraction analysis results show that the structure of x wt% CaZrO3–BaTiO3 ceramics changed from tetragonal phase to pseudocubic phase with increasing CaZrO3 content. The addition of CaZrO3 effectively decreased the sintering temperature of BaTiO3 ceramics and promoted the ceramic grain growth. The ceramic density increases first and then decreases with increasing CaZrO3 content. The dielectric performances of ceramics were optimal at a CaZrO3 content of 8 wt%. Owing to its larger grain and intensity of polarization, 8 wt% CaZrO3–BaTiO3 shows that a stable high permittivity (7145), a low dielectric loss (0.004), and the ceramic temperature coefficient of capacitance (TCC) values were within ± 22% in the range of –55 to 150 °C, thus meeting to Electronic Industries Alliance (EIA)-X8S regulations. The experimental results indicate that this two-step preparation process is an extremely effective method to enhance the ceramic dielectric performances, and adding a small amount of CaZrO3 effectively reduced the TCC absolute value of ceramics.