Gd2O3:Eu3+/PMMA Composite: Thermal and Luminescence Properties

Abstract

In recent years there is an increasing interest in obtaining and investigating composite materials that comprise nanoparticles as fillers and polymers as matrix. Such composites may display combined features of both components, and sometimes even novel properties resulting from their mutual interactions. It is important that both unique size-dependent properties of nanoparticles and favorable properties of polymer material remain preserved in the composite. In this research we investigated the possibility of obtaining composite material using as polymer matrix poly (methyl methacrylate) - PMMA and Gd2O3:Eu3+ nanopowder as filler. Three samples, containing 1, 3 and 5 mass % of Gd2O3:Eu3+, are prepared with a dispersion casting method. The composites exhibited characteristic red emission coming from the D-5(0) - GT F-7(2) transition of Eu3+ ion in Gd2O3:Eu3+. The observed lifetime values, around 1.1 ms, are quite high and suggest successful encapsulation of dopant ions in polymer through gadolinium oxide host. Experimental intensity parameters, transition rates and quantum efficiency of the D-5(0) emission are calculated from emission spectra using Judd-Ofelt theory. Influence of Gd2O3:Eu3+ filler on the modification of glass transition and thermo-degradable properties of the polymer matrix is also investigated. Thermal analyses give evidence of unchanged thermal stability of polymer phase in the composites.