Tunable emission from green to red in the GdSr₂AlO₅:Tb³⁺,Eu³⁺phosphorviaefficient energy transfer

Abstract

The emission spectra of GdSr2AlO5:2%Tb3+,x%Eu3+ (x = 0, 0.5, 1, 2, 3, and 5) under 275 nm excitation. (b) Variation tendency of the green emission of Tb3+ and the red emission of Eu3+.

Optical Properties of Red-Emitting Rb2Bi(PO4)(MoO4):Eu3+ Powders and Ceramics with High Quantum Efficiency for White LEDs

“…The intensity of 5 D 0 → 7 F 4 transition usually is very low in Eu 3+ doped phosphors and there are very few examples reported in the literature where this transition dominates the emission spectra. Some of these matrices are garnet structure compounds: Y 3 (Al,Ga) 5 O 12 :Eu 3+ [35]; orthophosphates: (Lu,Y,Gd,La)PO 4 :Eu 3+ [35], BiPO 4 :Eu 3+ [36]; borates: GdB 5 O 9 :Eu 3+ [37]; molybdates: Eu 2 Mo 4 O 15 [38], silicates: Na 2 ZnSiO 4 :Eu 3+ [39], Ca 2 Ga 2 SiO 7 :Eu 3+ [40]; aluminates: GdSr 2 AlO 5 :Eu 3+ [41]; niobates: K 2 LaNb 5 O 15 :Eu 3+ [42]; and even exotic uranyl phosphates: (Y,Eu,La)(UO 2 ) 3 (PO 4 ) 2 O(OH)·6H 2 O [43]. The inset in Figure 3b shows integrated emission intensity as a function of Eu 3+ concentration.…”

Controlled Synthesis of Tb3+/Eu3+ Co-Doped Gd2O3 Phosphors with Enhanced Red Emission

“…Figure 4 shows the excitation spectrum of the (Gd 0.93− x Tb 0.07 Eu x ) 2 O 3 ( x = 0.02–0.1) samples (reaction pH = 9.0, hydrothermal temperature: 140 °C, calcined temperature: 1100 °C) as a function of Eu 3+ content at an emission wavelength of 542 nm (Tb 3+ emission, Figure 4a) and 611 nm (Eu 3+ emission, Figure 4b), respectively. With monitoring at 542 nm, the PLE spectra of the (Gd 0.93− x Tb 0.07 Eu x ) 2 O 3 ( x = 0.02–0.1) system displays one strong and broad peak centered at ~308 nm which is ascribed to the 4 f 8 -4 f 7 5 d 1 transition of Tb 3+ [15], whereas by monitoring at 611 nm (Figure 4b), the PLE spectra of (Gd 0.93− x Tb 0.07 Eu x ) 2 O 3 phosphors contain two excitation bands at ~248 nm and ~308 nm which is ascribed to the charge transfer band (CTB) of Eu 3+ [16] and the 4 f 8 -4 f 7 5 d 1 transition of Tb 3+ , respectively. In addition, as we can see from the inline graph of b, the CTB excitation peak of Eu 3+ at ~258 nm overlapped the characteristic transition 8 S 7/2 - 6 I J of Gd 3+ implying the Gd 3+ →Eu 3+ energy transfer.…”

Microwave-assisted synthesis of ZnGa2−x−yEuxTbyO4 luminescent nanoparticles showing balanced white-light emission

“…[13][14][15][16][17][18] Multiple dopants in a single phosphor can yield energy transfer, which helps tune the emission to get the desired colour output. [19][20][21] This energy transfer further improves the efficiency of the phosphor significantly. In the present study, Tb 3+ and Eu 3+ were used as dopants to get the emission in the green and red regions, respectively.…”