Synthesis of Ba(Zr,Ti)₂O₅ particles using Zr/Ti-HPA with complexing of Ti-IPA and Zr using ZrOCl₂

For this study, Zr-substituted BaTi₂O₅ particles were synthesized using an aqueous solution method with peroxidized polytitanic acid as the starting material. After Zr/Ti heteropolyacids were synthesized by complexing Zr with polytitanic acid (Ti-IPA) in aqueous solution using ZrOCl₂, the obtained Zr/Ti heteropolyacids were mixed with barium hydroxide. Subsequently, the precipitate was dried and heat-treated at 1100 °C for 10 h. Thereby, we obtained single-phase Ba(Zr,Ti)₂O₅ powder. Using this method, BaTi₂O₅ was synthesized with up to 6 mol% Zr solid solution on Ti sites. These results were evaluated using XRD and XRF. The crystal structure and structural transition of the resulting Ba(Zr,Ti)₂O₅ were evaluated using Raman measurements. All Ba(Zr,Ti)₂O₅ samples showed a structural transition. The Curie temperatures T_c of BaTi₂O₅, BaZr_0.034Ti_0.966O₅, and BaZr_0.059Ti_0.941O₅ were, respectively, 480, 450, and 430 °C.