A single-composition tunable-emission phosphor NaTaOGeO4:Mn2+,Pr3+

The photoluminescence properties of NaTaOGeO4:Mn2+,Pr3+ are investigated in this paper. Their luminescent properties were characterized by means of diffuse reflection, photoluminescence excitation and emission spectra, lifetime and temperature-dependent emission spectra in the temperature range of 295-495 K. The phosphors NaTaOGeO4:Mn2+ show a strong broad absorption band centered at about 248 nm. The emission spectrum of NaTaOGeO4:Mn2+ shows orange-red emissions at 576 nm, owing to the 4T1 → 6A1 transition of Mn2+. With the introduction of Pr3+ ions into NaTaOGeO4:Mn2+, the emission spectra exhibit both the 4T1 → 6A1 transition of Mn2+ and the 3P0 → 3H4 transition of Pr3+ with the excited wavelength at 248 nm. The emission color of NaTaOGeO4: Mn2+, Pr3+ can be tuned by adjusting the relative concentration of Mn2+ and Pr3+ in a single component. The energy transfers from Mn2+ to Pr3+.