Synthesis and luminescence characteristics of Dy3+ doped KLa(PO3)4

Polycrystalline powders of KLa(1−x)Dyx(PO3)4 (x=0.5%, 1%, 5% and 10%) with linear chain have been grown by solid state reaction. The obtained powders are characterized by X-ray powder diffraction, FTIR and Raman spectroscopies. Emission, excitation spectra and decay curves analysis have been used to study the spectroscopic properties of Dy3+ in KLa(PO3)4. The photoluminescence spectra show two characteristic blue and yellow bands of Dy3+. The yellow-to-blue emission intensity ratios and CIE chromaticity coordinates have been determined from emission spectra to evaluate the emitted light as function of Dy3+ concentration. The measured decay rates for 4F9/2→6H15/2 deviated from exponential to non-exponential shape with increase of Dy3+ concentration. The observed non-exponential behavior of the decay curve has been fitted to Inokuti-Hirayama model, which indicates that the energy transfer between the donor and the acceptor is of dipole-dipole nature. The energy transfer, between the donor (excited Dy3+) and the acceptor (unexcited Dy3+), increases with Dy3+ ions concentration.