Luminescence properties and energy transfer investigations of BaAl2B2O7:Ce3+,Tb3+ phosphors

Symmetry dependent evolution of the Tb 3+ photoluminescence in Ba 6 ( RE 1−x Tb x ) 9 B 79 O 138 ( RE = La and Y, 0 ≤ x ≤ 1) and Ce 3+ -to-Tb 3+ sensitization effect: A re-visit to RE BaB 9 O 16

“…As assigned above, the two broad bands in the region of 220e290 nm in the spectrum of Ba 6 (La 0.3 Tb 0.7 ) 9 B 79 O 138 (y ¼ 0) are the typical 4f 8 /4f 7 5d 1 transitions of Tb 3þ , and the narrow peaks in the wavelength range of 283e385 nm originate from Tb 3þ fef transitions. Along with the codoping of Ce 3þ in the lattice, intense absorption bands with maxima at 258 and 275 nm emerge, which can be assigned to the 4f/5d transition of Ce 3þ [35]. Meanwhile, the 4f 8 /4f 7 5d 1 transitions of Tb 3þ are depressed.…”

“…Ce 3þ ion is widely used as a sensitizer for Tb 3þ emission [34,35]; here, in order to study such sensitization effect, we fixed the Tb 3þ concentration at x ¼ 0.70 and co-doped Ce 3þ with different contents in both BLBO and BYBO hosts, forming Ba 6 (RE 0.3Ày -Ce y Tb 0.7 ) 9 B 79 O 138 (RE ¼ La or Y, 0 y 0.3). Fig.…”

Enhanced luminescence intensity of novel red-emitting phosphor -Sr3Lu2(BO3)4:Bi3+,Eu3+ via energy transfer

“…The ratio of η o /η can be estimated by the ratio of the relative luminescence intensities, I so /I s without and with the activator. C is the total concentration of Bi 3+ and Eu 3+ ions and n = 6, 8, 10 which corresponds to dipole-dipole, dipole-quadrupole and quadrupole-quadrupole interaction [16][17][18][19]. The relationships between I so /I s and C Bi+Eu excited at 327 nm is illustrated in Figure 11(a), (b) and (c).…”

“…In an exchange interaction, the critical distance should be shorter than 5 Å thus, it is rational to hypothesize that the mechanism involved is multipolar interaction [16][17][18][19]. According to Dexter's energy transfer expressions of multipolar interaction [16][17][18][19] and Reisfeld's transfer approximation [16,17] the following relation can be obtained:…”

Enhanced luminescence properties and energy transfer in Ce3+ and Tb3+ co-doped NaCaBO3 phosphor

“…One of the strategies to solve the above problem is using Ce 3 þ as a sensitizer because it has a strong excitation band originating from allowed 4f-5d transitions, which could efficiently absorb the NUV light and transfer the excitation energy to Tb 3 þ , then result in strong sensitized green emission [7]. With this strategy, green phosphors with good luminescent properties, such as Sr 2 B 2 O 5 : Ce 3 þ , Tb 3 þ [8], La 6 Ba 4 (SiO 4 ) 6 F 2 : Ce 3 þ , Tb 3 þ [9] and BaAl 2 B 2 O 7 : Ce 3 þ ,Tb 3 þ [10] have been synthesized.…”