Synthesis and Annealing Effects on the Structure of Alumina by Polyol Mediated Process
Rare-earth ion (Eu3+ and Tb3+)-doped and undoped aluminum oxide powders have been prepared via polyol mediated synthesis. The precursors were aluminium nitrate, rare-earth (RE: Tb, Eu) nitrate and diethylene glycol. The powders were generated using low-temperature (Tmax ~ 200°C) and reaction time of 150 min. By controlling the acidity of the synthesis solution and the precursor concentration, sub-micrometric aggregates (about 300 nm) with spherical morphology were obtained. The powders of RE-doped Al2O3 were further investigated by photon correlation laser, X-ray diffraction, transmission electron microscope, scanning electron microscope, thermal analysis and photoluminescence emission spectra. The results showed that a-Al2O3 is formed at a temperature significantly lower than the solid sate reaction route. The luminescence of Al2O3 doped with 5 at.% Eu was observed with emission band in 614 nm and Al2O3 doped with 5 at.% Tb showed an emission band in 544 nm.
J. Federico Chávez Alcalá, Alejandro Cruz Ramírez and Ma. de los Ángeles Hernández Pérez
M.A. Flores González et al., "Synthesis and Annealing Effects on the Structure of Alumina by Polyol Mediated Process", Materials Science Forum, Vol. 691, pp. 44-48, 2011