title: Luminescence concentration quenching mechanism in Gd2O3:Eu3+.
abstract: Luminescence concentration quenching in Gd2O3:Eu(3+) nanocrystals results from strong interactions among O(2-) ions and Eu(3+) ions. Because all synthesized Gd2O3:Eu(3+) nanocrystals present the same cubic crystalline phase regardless of Eu(3+) concentration, it is possible to study the optical properties as a function of the dopant concentration. The emission intensities and lifetime curves for Gd2O3:Eu(3+) were analyzed by a simple rate equation model to study the interaction between the O(2-) ions and Eu(3+) ions. The rate equation model considers that such interaction is driven by the following energy transfer processes: the direct energy transfer (O(2-) → Eu(3+)), back-transfer (Eu(3+) → O(2-)), and direct energy migration (Eu(3+) → Eu(3+)). The exact solution of this model agrees with the experimental results, luminescence concentration quenching is reproduced and the corresponding energy transfer rates are reported. Quantitative results suggest that the direct energy transfer and direct energy migration processes are the main responsible for the luminescence concentration quenching, whereas the back-transfer process promotes the Eu(3+) emission.
authors: Instituto de Física "Ing. Luis Rivera Terrazas", Benemérita Universidad Autónoma de Puebla , Apartado Postal J-48, Puebla 72570, México.
authors: Octavio
authors: O
authors: Meza
authors: E G
authors: EG
authors: Villabona-Leal
authors: L A
authors: LA
authors: Diaz-Torres
authors: H
authors: H
authors: Desirena
authors: J L
authors: JL
authors: Rodríguez-López
authors: Elías
authors: E
authors: Pérez
mesh_terms: D004735:Energy Transfer; D005063:Europium / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry*; D007700:Kinetics; D049449:Luminescence; D008163:Luminescent Measurements; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D013816:Thermodynamics
chemical_list: D005063:Europium; C030581:gadolinium oxide; D005682:Gadolinium