Photoluminescence of Eu³⁺-, Tb³⁺-, Dy³⁺- and Tm³⁺-doped transparent GeO₂–TiO₂–K₂O glass ceramics

Abstract

In this paper, we present the photoluminescence properties of Eu3+-, Tb3+-, Dy3+- and Tm3+-doped potassium–titanium–germanate glasses and glass ceramics. Following the x-ray diffraction measurement, the glass structure was established. Compared to Eu3+-, Tb3+-, Dy3+- and Tm3+-doped glasses, their respective glass ceramics show stronger emissions due to the presence of the K2TiGe3O9 crystalline phase. For Eu3+-doped glass and glass ceramics, five emission bands centered at 578 nm , 592 nm , 614 nm , 653 nm and 702 nm have been observed with 394 nm excitation wavelength. Of them, 614 nm has shown a bright reddish-orange emission. For Tb3+-doped glass and glass ceramic, four emission bands centered at 490 nm , 549 nm , 586 nm and 621 nm have been observed with an excitation at 378 nm wavelength. Of them, 549 nm has shown a bright green emission. With regard to Dy3+:glass and glass ceramic, a blue emission band centered at 485 nm and a bright fluorescent yellow emission at 576 nm have been observed, apart from (665 nm) emission transition with an excitation at 387 nm , 4F7/2) wavelength. Emission bands of (650 nm) and (700 nm) transitions for the Tm3+:glass and glass ceramic, with excitation at (468 nm), have been observed. The stimulated emission cross sections of all the emission bands of Eu3+, Tb3+, Dy3+ and Tm3+:glasses and glass ceramics have been computed based on their measured Δλ (FWHM) and lifetimes (τm).

Photoluminescence properties and energy transfer of novel red phosphor Sr3P4O13:Eu3+, Bi3+

“…The energy levels of Eu 3 þ arise from the 4f n configuration and the emissions arising from f-f transitions yield sharp lines in the spectrum. The emission in Eu 3 þ corresponds to transitions from the excited state 5 D 0 level to the 7 F J (J ¼0, 1, 2, 3, 4, 5, 6) levels of the 4f 6 configuration [13].…”

Photoluminescence of Sm3+, Dy3+, and Tm3+-doped transparent glass ceramics containing CaF2 nanocrystals

“…Previously, for CaMoO 4 :Dy 3+ single crystals, the decay curves measured in the 10-170 K temperature range are not exponential and obey the Inokuti -Hirayama model for energy transfer for an electric quad- rupole -quadrupole interaction in the absence of diffusion among the donors [15]. Recently, we reported spectral results of various 1 mol% RE ions-doped oxyfluoride glasses/glass ceramics [16][17][18][19][20][21], in which the room temperature decay curves were well fitted to the single-exponential as in the present case. Recently, it is reported that in Er 3+ and Ho 3+ -doped nanocrystalline yttria, emission spectra obtained were with less intensity compared with bulk materials.…”

Synthesis and luminescent properties of NaZnPO4:Eu3+ red phosphors for white LEDs

“…(2). Generally, when Eu 3 þ ions are excited to any level above the 5 D 0 , there is a fast non-radiative multiphonon relaxation to this level and the emission form 5 D J( ¼ 1-3) to 7 F J are several orders smaller than that of 5 D 0 to 7 F J [13]. The τ 1 and τ 2 are attributed by the fast process and slow process.…”