Structural and Dielectric Characterization of Nanocrystalline (Ba, Pb)ZrO3 Developed by Reverse Micellar Synthesis

Abstract

Nanocrystalline zirconates of barium and lead have been synthesized using a modified reverse micellar route (avoiding alkoxides). The entire solid solution of Ba1−xPbxZrO3 (0≤x≤1) has been synthesized for the first time. Powder X‐ray diffraction studies show the monophasic nature of the powders after heating at 800°C except minor impurities of ZrO2 (2%–3%) at a higher lead content (x=0.50 and 0.75). The oxides crystallize in the cubic structure till x=0.25; for higher values, they crystallize in the orthorhombic structure. The particle size obtained from X‐ray line‐broadening studies and transmission electron microscopic studies is found to be in the range of 20–60 nm for all the oxides obtained after heating at 800oC. The grain size of the solid solution of Ba1−xPbxZrO3 (0≤x≤1) was found to increase with the lead content. The dielectric constant of the solids corresponding to Ba1−xPbxZrO3 (0≤x≤1) was found to be a maximum at x=0.50. Note that the cubic to orthorhombic transition is also observed between x=0.25 and 0.5. Dielectric properties with respect to variation in frequency and temperature are reported for these nanocrystalline oxides for the first time.