Vapor Pressure of the SrPbO3 Perovskite Phase

Published

April 1, 2000

Author(s)

Lawrence P. Cook, Winnie K. Wong-Ng

Abstract

The perovskite phase SrPbO₃ is important as a buffer and indicator of PbO chemical potential (at fixed p_O2 ) according to the reaction: 2 SrPbO₃ --> Sr₂PbO₄ + PbO(g) + 1/2 O2 (g), where the term PbO(g) includes several Pb-containing gaseous species. Total vapor pressures over SrPbO₃ were investigated by Knudsen cell vacuum thermogravimetry in the range 650 - 950 C, using pure PbO as a calibrant. Results indicate that within this range, vapor pressures for SrPbO₃ vary from ~12 % of those for pure PbO at the high temperature limit to ~21 % at the low temperature limit. Vapor pressures for SrPbO₃ are higher than those reported for the perovskite phases PbTiO₃ and PbZrO₃ by a factors of ~ 20 to 50 and ~ 2 to 4, respectively. The slopes of the d(log p) vs. 1/T data are similar for all three perovskites, indicating similar enthalpies of vaporization . The measured SrPbO₃ vapor pressures represent the maximum vapor pressures to be expected over phase assemblages with (Pb,Bi)-Sr-Ca-Cu-O (BSCCO) high Tc superconductors.

Citation

Ceramic Transactions

Volume

104

Pub Type

Journals

Keywords

BSCCO, high Tc superconductor related perovskit, SrPbO₃, vapor pressure

Citation

Cook, L. and Wong-Ng, W. (2000), Vapor Pressure of the SrPbO₃ Perovskite Phase, Ceramic Transactions (Accessed May 4, 2024)