Comparison of structural and spectroscopic properties of Ho3+-doped niobate compounds

Simon Guené-Girard (1) , Julia Courtois (1) , Marc Dussauze (2) , Jean-Marc Heintz (1) , Alexandre Fargues (1) , Jérôme Roger (3) , Marcelo Nalin (4) , Thierry Cardinal (1) , Veronique Jubera (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 ISM - Institut des Sciences Moléculaires
3 LCTS - Laboratoire des Composites Thermostructuraux
4 UNESP - Universidade Estadual Paulista Júlio de Mesquita Filho = São Paulo State University

Ho3+-doped YNbO4 and Y3NbO7 phosphors were synthesised via a co-precipitation synthesis route. Structural characterisation and spectroscopic properties were performed as a function of the Ho3+ concentration. The Rietveld type-refinement confirms the stabilisation of the pure monoclinic Fergusonite YNbO4 phase at the highest temperatures, but the quadratic phase is stabilised for the lowest temperature, whereas a pure cubic fluorite Y3NbO7 phase was observed for all of the heat treatments. Raman and infrared spectroscopies were used to compare the cation-oxygen vibrational modes. Emission spectra and up-conversion processes were obtained under excitation at 445 and 975 nm respectively. For a similar Ho3+ content, the energy transfers observed show differences between the two crystalline compounds that are related to a stronger interaction between the holmium cations in the fluorite host lattice.

Mots clés: energy transfer; rare earth; niobate; luminescence; Raman

Domaines: Matériaux

Simon Guené-Girard, Julia Courtois, Marc Dussauze, Jean-Marc Heintz, Alexandre Fargues, et al.. Comparison of structural and spectroscopic properties of Ho3+-doped niobate compounds. Materials Research Bulletin, 2021, 143, pp.111451. ⟨10.1016/j.materresbull.2021.111451⟩. ⟨hal-03273669⟩