CHARACTERIZATION OF TITANIUM AND ZIRCONIUM VALERATE SOL-GEL FILMS

FTIR and XPS have been used to characterize titanium and zirconium val erate thin films prepared using sol-gel techniques. Films were prepare d by hydrolysis of titanium(IV) isopropoxide or zirconium(IV) n-propox ide in excess valeric acid at room temperature. Film solution chemistr y, from precursors to cast films, was followed with FTIR. The structur e and chemical composition of films spin cast from fresh and day-old s olutions were determined. Results of these studies suggest that all fi lms consist of a metal-oxygen polymer backbone coordinated with bident ate valerate ligands. No evidence for the presence of alkoxide ligands has been found. A small amount of water is present in all cast films. While solution experiments indicate that the zirconium film structure does not change with solution reaction time, carboxylate ligand conce ntrations are higher in titanium films made from aged solutions. Titan ium films made from aged solutions contain slightly less than 1.5 vale rate ligands/titanium atom. Zirconium films are more highly carboxylat ed with almost two valerate groups per metal center.