High energy transfer in Dy3+ /Sm3+co-doped transparent borosilicate glass-ceramics containing novel Na5Y9F32 nanocrystals for w-LEDs applications

Abstract Transparent borosilicate glasses doped with Dy3+, Sm3+ and Dy3+/Sm3+ were made by a melt-quenching method. And glass ceramics (GCs) containing novel Na5Y9F32 nanocrystals were developed by heating the precursor glasses (PGs) at a specified temperature. The related crystalline phase and the morphologies of cubic Na5Y9F32 nanocrystals inside GCs were examined further. When excited at various wavelength, the emission color can experience from yellow (0.3813, 0.4207) to white (0.3219, 0.3316) by tuning the Sm3+ content. The energy transfer (ET) among the Dy3+/Sm3+ ions is confirmed by decay curves with photoluminescence spectra and the maximum energy transfer efficiencies were estimated to be 73.23%. The mechanism of dipole-dipole interaction for energy transfer (ET) between Dy3+ and Sm3+ ions can be explained by the analysis of Inokuti-Hirayama (IH) model and the formula of Dexter's energy transfer. The prepared GCs exhibit good thermal stability with the rise of temperatures. These obtained results imply that the Dy3+/Sm3+ co-doped transparent GCs might be a meaningful material for white-light emitting diode (w-LED) applications.