![Sample our Engineering & Technology journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5933/TOC-Subject-Sample-2021-Engineering-Tech.jpg"})
Abstract
This article discusses a mechanism for preparing perovskite powders, 0.75Pb(Ni1/3Nb2/3)O3-0.25PbTiO3 (PNN-PT), using a semichemical method (SCM).Precursors were prepared by adding aqueous Ni(Ac)2 solutions to an alcohol slurry of PbO, Nb2O5, and TiO2. The TG-DTG and DSC analysis of the precursors and XRD analysis of the powders at different thermal treatment temperatures showed that the reaction mechanisms in this method differ from those in the conventional mixed-oxide method. The aqueous Ni(Ac)2 solution reacted with PbO to form Pb(Ac)2 · Pb(OH)2 · H2O and Ni(OH)2, which decomposed to form nascent PbO and NiO, thereby improving the reactivity and distribution of PbO and NiO. Pb3Nb2O8 and NiNb2O6 formed and were easily converted into the perovskite phase during the thermal treatment process. At a thermal treatment temperature of 850°C, the content of the perovskite phase reached 98%. Pyrochlore-free PNN-PT ceramic was obtained after 2 h of sintering at 1100°C, and its dielectric properties were found to be excellent at temperatures ranging between −55 and 120°C.
Acknowledgments
This work was supported by the Science and Technology Foundation of Xi'an City (GG05068) and the Natural Science Foundation of Shaanxi Province (2001H06).