General Nonaqueous Sol-Gel Synthesis of Nanostructured Sm2O3, Gd2O3, Dy2O3, and Gd2O3:Eu3+ Phosphor

In this paper, we report oil the synthesis of nanostratured rare earth oxides (Sm2O3, Gd2O3. Dy2O3) via a facile benzyl alcohol based nonaqueous sol-gel process followed by calcination at Moderate temperature During the synthesis, rare earth acetylacetonates were used as the precursors. The resulting samples were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and photoluminescent spectroscopy. The final nanostructured RE2O3 products were observed to possess two typical shapes: stacks Of Ultrathin nanodisks for Sm2O3 and hierarchical nanosheet microspheres for Gd2O3 and Dy2O3, respectively. This method could be extended to prepare high-quality luminescent Gd2O3:Eu3+ flowerlike superstructures with I strong red emission corresponding to (5)Do -> F-7(2) transition (612 nm) of Eu3+ Under ultraviolet excitation (260 11111). The possible formation mechanisms of the ultrathin nanodisk stacks and hierarchical nanosheet microspheres are proposed oil the basis of the characterization results. This study provides an alternative nonaqueous approach for the synthesis of nanostructured rare earth oxides.