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

• Autor(a) principal: Guene-Girard, S.
• Data de Publicação: 2021
• Outros Autores: Courtois, J., Dussauze, M., Heintz, J-M., Fargues, A., Roger, J., Nalin, M. [UNESP], Cardinal, T., Jubera, V.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.materresbull.2021.111451; http://hdl.handle.net/11449/221859
• topic: Energy transfer; Luminescence; Niobate; Raman; Rare earth

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.