Tb3+ Fluorescence and Nonradiative Energy Transfer from Gd3+ to Tb3+ in Borate Glass

Abstract

The fluorescence behavior of Gd3+ and Tb3+ has been studied with the ions dissolved together in a Calibo-1 glass host. The two ions form a coupled system so that energy absorbed by Gd3+ is transferred to Tb3+ by a nonradiative mechanism and is then emitted as Tb3+ fluorescence. When Tb3+ is incorporated alone into this glass, concentration quenching effects are observable. These have been found to be due to the shortening of the Tb3+ 5D4 lifetime, which in turn is due to the Tb3+ ions being packed closer together as the concentration of Tb3+ is increased. It is proposed that this gives rise to ``chains'' of Tb3+ ions along which energy can migrate, by a nonradiative transfer mechanism, to sinks in the structure. The rate of internal conversion from Tb3+ 5D3 to Tb3+ 5D4 has also been studied as a function of concentration. The results have been interpreted as being due to the formation of Tb3+-Tb3+ resonance-coupled pairs, which causes the rate of internal conversion to increase as the concentration of Tb3+ increases. The effects of changes in temperature and base glass composition on the Tb3+ 5D4 lifetime have also been investigated and are reported.

Enhanced luminescent properties of Tb3+ ions in transparent glass ceramics containing BaGdF5 nanocrystals

“…The 228 nm band corresponds to 4f 8 → 4f 7 5d 1 transition of Tb 3+ , and the 318, 351, 376 and 483 nm bands are associated with the transitions from the ground state 7 F 6 to 5 D 1,2,3,4 levels, respectively [26][27][28]. It should be pointed out that the 273 nm band can be assigned to 8 S 7/2 → 6 P 7/2 transition of Gd 3+ , which indicates that there is the energy transfer from Gd 3+ to Tb 3+ [29][30][31]. Additionally, for the glass ceramic specimens, the excitation band at about 228 nm is apparently intensified compared with the glass.…”

White light emission from Eu3+/Tb3+/Tm3+ triply-doped aluminoborate glass excited by UV light

“…1 show the emission and excitation spectra of Tb 3 + in CaAlB glass matrix. Under 378 nm excitation, the emission spectrum exhibits two strong emission peaks at 488 and 544 nm, corresponding to the 5 D 4 → 7 F 6 and 5 D 4 → 7 F 5 transitions of Tb 3 + , respectively [17]. The excitation spectrum for 544 nm wavelength shows two sharp lines in the 310-510 nm range corresponding to the 4f-4f transitions of Tb 3 + , which were assigned to 7 F 6 → ( 5 H 7 , 5 D 0,1 ) (317 nm), 7 F 6 → ( 5 L 9 , 5 G 4 ) (352 nm), 7 F 6 → ( 5 D 3 , 5 G 6 ) (378 nm), and 7 F 6 → 5 D 4 (485 nm) [18].…”

Photoluminescence of the MgSO4:Tb3+,Na+ Powder Phosphor

“…This is quite different from the present result: In MgSO 4 :TbF 3 (x mol%), the intensity ratios of the 5 D 3 → 7 F 6 band to the 5 D 4 → 7 F 6 band were 0.82, 0.26 and 0.19% for x = 0.5, 1 and 2 mol%, respectively, at 300 K. The quenching of the 5 D 3 series is usually explained by the cross-relaxation process between 5 D 3 → 5 D 4 of the emitting Tb 3+ and 7 F 6 → 7 F 0 of the neighboring Tb 3+ . 10,11) As the Tb 3+ concentration is increased, the relaxation from the 5 D 3 to 5 D 4 state is increased. This corresponds well to the above result.…”