Atmospheric pressure synthesis of heavy rare earth sesquioxides nanoparticles of the uncommon monoclinic phase

We report, for the first time, the atmospheric pressure synthesis of nonagglomerated nanoparticles (2060 nm in diameter) of the uncommon monoclinic phase of some heavy rare earth sesquioxides RE2O3 (RE=Dy, Ho, Er, Tm, and Yb). The RE2O3 nanoparticles, prepared by a flame synthesis process, were characterized by Xray diffraction, transmission electron microscopy, and electron energy loss spectroscopy. Monoclinic nanoparticles were formed when the flame temperature was sufficiently high; lower temperatures led to the formation of the normal cubic (Ctype) phase. We explain the formation of the uncommon monoclinic phase on the basis of pressuretemperature phase equilibria, and the extra internal pressure induced by surface curvature of the nanoparticles.

Guo, B., Harvey, Z. S., Neil, J., Kennedy, I. M., Navrotsky, A., & Risbud, S. H.

Atmospheric pressure synthesis of heavy rare earth sesquioxides nanoparticles of the uncommon monoclinic phase Academic Article