Structure and fluorescence properties of Dy-doped alkaline-earth borophosphate glasses

Abstract

[EN] Dysprosium- doped borophosphate glasses, containing the divalent cations Mg2+, Ca2+, Sr2+, Ba2+, and Zn2+, are prepared by the melt- quenching technique. The struc-ture of the glasses is investigated by Raman, infrared, and nuclear magnetic resonance (NMR) spectroscopies and the fluorescence properties are determined. The Dy3+emission lifetime increases with an increasing ionic field strength and its maximum is observed in the Mg2+ and Zn2+ containing glasses. This result can be explained by the stronger M- O bonding which causes a rearrangement of the borophosphate network and creates a local Dy3+ environment of comparably low symmetry. This is in agree-ment with the Raman spectra and the evolution of the molar volume. The effect of the B/P variation on the emission properties of Dy3+ is investigated in a second series of glasses where the emission lifetime is found to be maximum at 10 mol% B2O3 ; This paper is a part of the dissemination activities of the project FunGlass. This project has received funding from the European Union´s Horizon 2020 research and innovation program under grant agreement No 739566. This work was also supported by the Slovak Research and Development Agency under contract No. APVV-17-0049 and by grant VEGA 1/0527/18. NST and EIK acknowledge support by the project "National Infrastructure in Nanotechnology, Advanced Materials and Micro-/Nanoelectronics" (MIS 5002772), funded by the Operational Programme "Competitiveness, Entrepreneurship and Innovation" (NSRF 2014-2020) and co-financed by Greece and the European Union (European Regional Development Fund).