Tailoring the Composition of Eu(3+)-Doped Y3NbO7 Niobate: Structural Features and Luminescent Properties Induced by Spark Plasma Sintering.

Ka-Young Kim (1) , U-Chan Chung (1) , Brice Mutulet (1) , François Weill (1) , Alain Demourgues (1) , Julie Rossit (1) , Jean-Marc Heintz (1) , Amélie Veillere (1) , Veronique Jubera (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

The defective fluorite-related Y3NbO7 host lattice was doped with Eu(3+) ions to understand the influence of spark plasma sintering (SPS) process on this host lattice. The intrinsic disorder due to the occurrence of oxygen vacancies results in amorphous-type responses of the luminescent cations, and the spectral distribution varies as a function of the niobium content. Two spectral fingerprints of europium emissions were clearly enhanced. The correlation between luminescence, X-ray diffraction, and electron diffraction characterizations shows the existence of local inhomogeneity. Indeed, the particular nonequilibrium sintering conditions allowed pointing out a lack of miscibility within the Y3NbO7 solid solution domain. Thus, the SPS pellet is a composite of two extreme compositions. This phase demixing is mainly induced by the pressure coupled with a current effect that makes possible ionic migration in this Y3NbO7 ionic conductive matrix.

Domaines: Matériaux

Ka-Young Kim, U-Chan Chung, Brice Mutulet, François Weill, Alain Demourgues, et al.. Tailoring the Composition of Eu(3+)-Doped Y3NbO7 Niobate: Structural Features and Luminescent Properties Induced by Spark Plasma Sintering.. Inorganic Chemistry, 2017, 56 (8), pp.4495-4504. ⟨10.1021/acs.inorgchem.7b00088⟩. ⟨hal-01520638⟩