Properties of the (Y_0.75Gd_0.25)₂O₃:Eu³⁺ Scintillating Nanopowder

Željka Andrić,^a Radenka Krsmanović,^a Miodrag Mitrić,^a Zoran Marković,^a Bruno Viana^b and
Miroslav D. Dramićanin^a*

^a Institute of Nuclear Sciencies “Vinča,” P.O. Box 522, 11000 Beograd, Serbia
^b Laboratoire de Chimie de la Matière Condensée de Paris (ENSCP), CNRS UMR 7574 11, rue P et M Curie, 75231 Paris cedex 05, France
* Corresponding author: E-mail: dramican@vin.bg.ac.yu

Abstract
Yttrium-gadolinium-oxide phosphors are regarded promising host for many important optical applications, for example in medical diagnostic X-ray systems and plasma displays. In this work, we investigated the procedure for (Y_0.75Gd_0.25)₂O₃:Eu³⁺ nanopowder synthesis using polymer complex solution (PCS) method based on polyethylene glycol (PEG) as fuel. Detailed information, on both the structure and luminescence, are obtained using X-ray powder diffraction, electron microscopy and luminescence spectroscopy. The synthesized powder consists of nanoparticles of about 36 nm in size, and has excellent structural ordering in cubic bixbyte structure (space group Ia3). Unit cell parameter, ionic coordinates, crystal coherence size and microstrains are determined from Rietveld analysis. Luminescence emission measurements show characteristic transition of the trivalent europium ion incorporated into insulating host. Splitting of the Stark components of the ⁷F₁ manifold is presented. ⁵D₀, ⁵D₁ and ⁵D₂ decay time values are measured to obtain information on different kinetic processes occurring for these three emitting levels.

Keywords: Combustion synthesis, yttrium-gadolinium oxide, PEG, luminescence spectroscopy.