Spectroscopic studies of Dy3+ doped borate glasses for cool white light generation

The Dy3+ ions doped Na2O-ZnO-Al(2)O3-B2O3 (BAZN) glasses with variable doping concentrations were synthesized by melt-quenching technique. The XRD pattern reveals amorphous nature of the as-synthesized glass. The FT-IR spectrum reveals various stretching and bending vibration of aluminates, borate and some other groups. The emission spectra exhibit two intense bands at around 482 nm (blue) and 575 nm (yellow) corresponding to the F-4(9/2)->(/2) and F-9/2 -> H-6(13/2) transitions respectively. The CIE chromaticity coordinates of the as-synthesized glases are lying in white region and in proximity to the coordinates for white light specified by National Television Standard Committee and commercial phosphor converted white light emitting devices. The decay profile of BAZN glasses showed bi-exponential behavior due to the energy transfer mechanism from excited donr ion to unexcited acceptor ion. The above-mentioned studies show potential of the as-synthesized Dy-3 dop(+)ed BAZN glasses in solid state lighting applications.