Synthesis, characterization and microwave dielectric properties of nanocrystalline CaZrO3 ceramics

Abstract The synthesis, characterization and microwave dielectric properties of ceramic calcium zirconate (CaZrO 3 ) nanoparticles synthesized by combustion process are reported in this paper. The X-ray diffraction studies confirm that phase formation is complete on annealing the as-prepared sample at 700 °C. The average particle size calculated from full wave half maximum (FWHM) using Scherer formula is ∼33 nm. The phase purity of CaZrO 3 ceramic has been examined using differential thermal analysis (DTA), thermo gravimetric analysis (TGA) and Fourier transform of infrared spectroscopy (FTIR). The nanopowder was sintered at an optimized temperature1500 °C for 4 h and obtained about 98% of the theoretical density. The morphology of the sintered pellet was studied with scanning electron microscopy (SEM). The dielectric constant of 23.8, quality factor of ( Q u × f ) of 30600 GHz and a temperature coefficient of resonant frequency ( τ f ) of 1.4 ppm/°C is observed at 5.65 GHz. The high quality factor and very low τ f makes this sample suitable for microwave dielectric resonator applications.