Hydroxypropyl-β-cyclodextrin as a versatile additive for the formation of metastable tetragonal zirconia exhibiting high thermal stability
- 29 November 2012
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in CrystEngComm
- Vol. 15 (11), 2076-2083
- https://doi.org/10.1039/c2ce26540k
Abstract
Single-phase tetragonal zirconium oxides with enhanced phase stability were successfully synthesized by a precipitation procedure, using hydroxypropyl-β-cyclodextrin (HP-β-CD) as a new macromolecular additive. The samples were prepared in the presence of controlled amounts of HP-β-CD by precipitation of a zirconium oxychloride solution in an aqueous ammonia solution and then annealed at 600 °C to produce the pure tetragonal phase. The as-prepared ZrO2 particles are composed of nanocrystallites with coherent scattering region sizes of the order of 40 nm at temperatures as high as 600 °C. The formation of the t-phase was investigated at different stages of the process by XRD, TGA–TDA, FTIR and conductivity measurements. The process of crystallization of the hydrous zirconia precursor was found to be retarded by the binding of HP-β-CD to the zirconium metal centres, further leading to structure-controlled t-ZrO2 nanocrystals with increasing temperature up to 800 °C. The beneficial effect of HP-β-CD was related to its ability to be partially deprotonated in the aqueous ammonia solution and interact with the Zr(IV) species in the early stage of the synthesis. This hypothesis was supported by additional controlled syntheses of materials using other cyclodextrin derivatives.Keywords
This publication has 42 references indexed in Scilit:
- A controllable transformation in copper valence states and its applicationsDalton Transactions, 2011
- Selective Growth of Monoclinic and Tetragonal Zirconia NanocrystalsJournal of the American Chemical Society, 2010
- The effect of processing parameters on particle size in ammonia-induced precipitation of zirconyl chloride under industrially relevant conditionsPowder Technology, 2009
- Methylated cyclodextrins: an efficient protective agent in water for zerovalent ruthenium nanoparticles and a supramolecular shuttle in alkene and arene hydrogenation reactionsDalton Transactions, 2007
- Chemical-Composition-Dependent Metastability of Tetragonal ZrO2 in Sol−Gel-Derived Films under Different Calcination ConditionsChemistry of Materials, 2005
- Effect of maltose for the crystallization of tetragonal zirconiaMaterials Letters, 2004
- Effects of organic additives on hydrothermal zirconia nanocrystallitesJournal of Crystal Growth, 2003
- UV Raman spectroscopic study on the phase transformation of ZrO2, Y2O3–ZrO2 and SO42−/ZrO2Journal of Raman Spectroscopy, 2002
- Role of oxoanions in the stabilization of tetragonal zirconiaJournal of Materials Chemistry, 1994
- Spectroscopic studies on β-cyclodextrinVibrational Spectroscopy, 1990