Fabrication and Phase Transition of Bi₂O₃-Doped Sr₃Ti₂O₇ Ceramics

Abstract

Sr3Ti2O7ceramics with pure Ruddlesden-Popper phase (RP) were synthesized by conventional solid state method. The influences of the Bi2O3addition, the calcination temperature, and the sintering temperature on the phase transition were studied. The results showed that for the samples without doping Bi2O3, the main phase of calcined powders is Sr3Ti2O7, but pure Sr3Ti2O7phase cannot be obtained in the sintered ceramics because of the Sr3Ti2O7decomposition. For the samples doping with Bi2O3, although the main phase of the calcined powder is SrTiO3, the single RP phase Sr3Ti2O7can be obtained after sintering, which should be attributed to the formation of Sr3Bi2O6phase during calcination stage. Bi2O3addition is beneficial to the formation of the Sr3Ti2O7RP phase.