METAL DIOLATES - USEFUL PRECURSORS FOR TAILOR-MADE OXIDES PREPARED ATLOW-TEMPERATURES

Diolates of titanium and heterometallic diolates of the combinations M g/Si, Mg/Ti, Mg/Zr and Ti/Si were prepared by reacting alcoholates [e. g. Ti(OC2H5)(4), Mg(OCH3)(2) . CH3OH] with alpha,omega-diols like pent ane-1,5-diol. The resulting diolates are probably of polymeric nature and do not form single crystals. Structural information was obtained b y infrared spectroscopy, thermal analysis and X-ray absorption spectro scopy at the Mg and Si K-edges. Thermal decomposition of such diolates led to oxides with distinct morphology at comparatively low temperatu res (540-800 degrees C). For the heterometallic diolates the thermal d ecomposition in most cases led to binary, sometimes metastable oxides. The morphology of the oxides strongly depended on the nature of the p recursor.