Modification of Different Zirconium Propoxide Precursors by Diethanolamine. Is There a Shelf Stability Issue for Sol-Gel Applications?

International Journal of Molecular Sciences

Gerald I. Spijksma¹  Dave H. A. Blank¹  Henny J. M. Bouwmeester¹ 

[1] Inorganic Materials Science, Faculty of Science & Technology, and Mesa ⁺ Research Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands; E-Mails:

关键词: precursor chemistry;    molecular structure;    nona-coordinated zirconium;   

DOI  :  10.3390/ijms10114977

来源: mdpi

【 摘 要 】

Modification of different zirconium propoxide precursors with H₂dea was investigated by characterization of the isolated modified species. Upon modification of zirconium n-propoxide and [Zr(OⁿPr)(OⁱPr)₃(ⁱPrOH)]₂ with ½ a mol equivalent of H₂dea the complexes [Zr₂(OⁿPr)₆(OCH₂CH₂)₂NH]₂ (1) and [Zr₂(OⁿPr)₂(OⁱPr)₄(OCH₂CH₂)₂NH]₂ (2) were obtained. However, ¹H-NMR studies of these tetranuclear compounds showed that these are not time-stable either in solution or solid form. The effect of this time instability on material properties is demonstrated by light scattering and TEM experiments. Modification of zirconium isopropoxide with either ½ or 1 equivalent mol of H₂dea results in formation of the trinuclear complex, Zr{η³μ₂-NH(C₂H₄O)₂}₃[Zr(OⁱPr)₃]₂(iPrOH)₂ (3) countering a unique nona-coordinated central zirconium atom. This complex 3 is one of the first modified zirconium propoxide precursors shown to be stable in solution for long periods of time. The particle size and morphology of the products of sol-gel synthesis are strongly dependent on the time factor and eventual heat treatment of the precursor solution. Reproducible sol-gel synthesis requires the use of solution stable precursors.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.