New quenched-in fluorite-type materials in the Bi2O 3-La2O3-PbO system: Synthesis and complex phase behaviour up to 750 °c

Journal article

New quenched-in fluorite-type materials with composition (BiO 1.5)0.94-x(LaO1.5)0.06(PbO) x, x = 0.02, 0.03, 0.04 and 0.05, were synthesised by solid state reaction. The new materials undergo a number of phase transformations during heating between room temperature and 750 °C, as indicated by differential thermal analysis. Variable temperature X-ray diffraction performed on the material (BiO1.5)0.92(LaO1.5) 0.06(PbO)0.02 revealed that the quenched-in fcc fluorite-type material first undergoes a transformation to a β-Bi 2O3-type tetragonal phase around 400 °C. In the range 450-700 °C, α-Bi2O3-type monoclinic, Bi 12PbO19-type bcc and β1/β 2-type rhombohedral phases, and what appeared to be a ε-type monoclinic phase, were observed, before a single-phase fluorite-type material was regained at 750 °C. © 2010 Elsevier Ltd © 2011 Elsevier Ltd. All rights reserved.

Authors: Webster, N; Hartlieb, K; Saines, P; Ling, C; Lincoln, F

• Journal: Materials Research Bulletin
• Volume: 46
• Issue: 4
• Pages: 538-542
• Publication date: 2011-04-01
• DOI: 10.1016/j.materresbull.2010.12.035
• ISSN: 0025-5408
• Language: English
• Keywords: A. Ceramics; D. Phase transitions; A. Oxides; C. X-ray diffraction