Combinatorial processing of mixed-metal oxide nanopowders along the ZrO2-Al2O3 tie line using liquid-feed flame spray pyrolysis (LF-FSP)

Richard Laine

M. Kim and R.M. Laine (2007)

J. Ceramic Processing Research, 8:129-36.

We report here the synthesis of (ZrO2)1-x(Al2O3)x nanooxide powders with molar ratios that span the ZrO2-Al2O3 composition
range. Liquid-feed flame spray pyrolysis (LF-FSP) of mixtures of N(CH2CH2O)3Al (alumatrane) and Zr(CH3CH2COO)2(OH)2
precursors dissolved in ethanol, were aerosolized with O2, combusted at temperatures of 1500-2000oC and rapidly quenched
thereafter to provide (ZrO2)1-x(Al2O3)x nanopowders of selected compositions. All powders exhibit average particle sizes (APSs)
< 20 nm and corresponding surface areas of ≈50 m2/g when produced at rates of 100-300 g/h. The as-processed powders were
characterized in terms of phase, APS, specific surface area, composition, and morphology by BET, XRD, XRF, SEM, TEM,
FT-IR, and TGA-DTA. The presence of δ-alumina and tetragonal zirconia is observed over most of the compositions studied.
Furthermore, this phase segregation leads to the formation of core-shell materials. Evidence is presented suggesting the
incorporation of Zr2+/3+ ions above the published solubility limit of ZrO2 in δ-alumina.

nanopowders, flame spray pyrolysis