Published online by Cambridge University Press: 10 May 2016
Pb2+-doped (Sr1−xPbx)3Ti2O7 (SPT) ceramics were fabricated by a solid state reaction. The stability and lattice structure of Sr3Ti2O7 and Sr4Ti3O10 Ruddlesden–Popper (RP) phases were studied as a function of Pb2+ content and sintering atmosphere. X-ray diffraction indicates that SrO(SrTiO3)n RP phase formation is sensitive to the Sr:Ti ratio of the raw materials and is a complex circularly iterative process. When the PbO concentration is less than x = 0.03, pure Sr3Ti2O7 can be obtained. Sr4Ti3O10 was found to be the main phase in the SPT samples for x ≥ 0.075. Pb2+ stabilizes SrO(SrTiO3)n RP phases by substitution for Sr2+ which reduces the lattice stress of the RP phase. It was observed that SrO vaporization losses at high temperature can be compensated by the decomposition of the intermediate SrPbO3 phase at lower temperature.