Formation of oxygen deficient BaPbO_3‐x by oxalate decomposition

Abstract

BaPbO 3 is assumed to be oxygen deficient but the exact determination has never been reported. The aim of this study is to investigate the correlation between synthetic conditions and the resulting oxygen deficiency of BaPbO 3-x . The formation of BaPbO 3-x by decomposition of barium-and lead oxalate up to 850 °C is significantly faster compared to conventional high temperature solid state reactions of oxide compounds. The discrete reaction steps were studied by simultaneous thermal analysis and X-ray powder diffraction. The oxygen content was determined by temperature-programmed reduction analysis. It is shown that the formation process is very sensitive to the chosen starting materials leading to different oxygen deficits caused by partial oxidation from Pb 2+ to Pb 4+ . The resulting perovskites show chemical compositions of BaPbO 2.74 and BaPbO 2.82 . The varying oxygen deficits should have an effect on structural properties.

Feeble Metallicity and Robust Semiconducting Regime in Structurally Sensitive Ba(Pb, Sn)O$_3$ Alloys

“…The same observation has been made by Namtame et al 29 . In fact Franz et al have synthesized the BaPbO 3 with chemical composition BaPbO 2.74 and BaPbO 2.82 38 . The authors also observed that the BaPbO 3 can only be synthesized with vacancies.…”