Luminescence and structural analysis of Ce and Er doped and Ce-Er codoped CaScSiO garnets: influence of the doping concentration in the energy transfer processes

• Published in: RSC advances 2016-02, Vol.6 (18), p.1554-1561
• Main Authors: Fernández-González, R, Velázquez, J. J, Rodríguez, V. D, Rivera-López, F, Lukowiak, A, Chiasera, A, Ferrari, M, Gonçalves, R. R, Marrero-Jerez, J, Lahoz, F, Núñez, P
• Format: Article
• ISSN: 2046-2069
• DOI: 10.1039/c5ra22630a

We present research on Ca 3 Sc 2 Si 3 O 12 garnets doped with Ce 3+ and Er 3+ ions that were synthesized by the freeze-drying precursor method. The structural characterization was performed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) images of the calcined material were studied. Nanocrystals of Ca 3 Sc 2 Si 3 O 12 were obtained by calcining the precursor at 1200 °C for 4 h with a mean size of about 100 nm. The luminescence features of Ce 3+ and Er 3+ doped samples indicated that these ions are effectively incorporated into the crystalline phase. In addition, codoping with Ce 3+ -Er 3+ ions results in energy transfer processes from Ce 3+ to Er 3+ ions which led to the enhancement of near-infrared luminescence at 1.5 μm. The efficiency of this non-radiative energy transfer process has been studied by means of excited state dynamics as a function of the doping concentration. From these results we have found that near-infrared Er 3+ luminescence efficiency under VIS Ce 3+ excitation is at maximal for 1Ce 3+ -1Er 3+ codoped Ca 3 Sc 2 Si 3 O 12 garnets (in mol%). Luminescence quenching at higher Er 3+ ion concentrations is observed. We present a structural a spectroscopy analysis of Ca 3 Sc 2 Si 3 O 12 garnets doped with Ce 3+ and Er 3+ ions that were synthesized by the freeze-drying precursor method. Efficient energy transfer has been obtained result in an enhanced NIR emission.