Dysprosium-doped oxyfluoride glasses and nanocrystalline glass ceramics have been synthesized and studied by x-ray diffraction, absorption, and visible and near-infrared emission spectra. The samples emit intense white light when populating the F49/2 level with a 451 nm laser light and, from the visible emission spectra, yellow to blue intensity ratios and chromaticity color coordinates have been calculated and their relative variation have been discussed based on the concentration of Dy3+ ions and the heat treatment conditions used to prepare the glass ceramics. Infrared emission has also been observed in glasses and glass ceramics after laser excitation at 800 nm, showing bands at 1.33 and 1.67 μm, useful for optical amplification in fiber amplifiers.

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Trivalent dysprosium‐doped cubic yttrium oxide (Y2O3) nanophosphors were prepared by combustion synthesis using glycine as fuel. The resulting products were characterized by Raman and FT‐IR spectra to evaluate the vibrational features of the samples. X‐ray diffraction patterns confirmed the formation of a pure cubic phase of Y2O3. The morphology and selective area electron diffraction measurements were carried out using transmission electron microscopy (TEM) and field‐emission scanning electron microscopy. From TEM, it is observed that as‐prepared particles have average crystallite sizes of around 23 nm. The luminescent and dynamic properties of Y2O3:Dy3+ were examined as a function of temperature and different concentrations of Dy3+. The luminescence study reveals that these phosphors predominantly exhibit greenish‐yellow emission due to strong 4F9/2→6H13/2 transition at 575 nm and a feeble 4F9/2→6H15/2 transition at 488 nm. These results show that the relative luminescence intensity of emission bands changes with different heating temperatures, while the greenish yellow color luminescence as well as Commission International d'Eclairage chromaticity coordinates extracted from the emission spectra were not affected significantly. The strong greenish‐yellow emission of Y2O3:Dy3+ phosphor may be useful for applications in solid‐state white lamps for general illumination purposes.

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