ZIRCONIUM TITANATE FROM SOL-GEL SYNTHESIS - THERMAL-DECOMPOSITION ANDQUANTITATIVE PHASE-ANALYSIS

Oxides precursors ZrxTi1-xO2 (x = 0.22, 0.39, and 0.60) were prepared by a hydrolytic sol-gel process. The amorphous mixed oxides are homoge neous as deduced from electron microscopy and XPS studies. The crystal lization of these amorphous oxides was studied by TGA-DTA and thermodi ffractometry. Quantitative analysis of the crystalline phases, obtaine d at 1000 degrees C, was carried out by the Rietveld method. The sampl es are mixtures of TiO2, Zr5Ti7O24, and ZrO2 oxides, and the stoichiom etry of the stable zirconium titanate phase was found to be Zr5Ti7O24 and not ZrTiO4 (=Zr6Ti6O24). In this work, the power of Rietveld refin ements to determine phase ratios of very related land thus very overla pped) phases is shown. (C) 1998 Academic Press.