Synthesis and Photoluminescence Characteristics of High Color Purity and Brightness Li₃Ba₂Gd₃(MoO₄)₈:Eu³⁺ Red Phosphors

Abstract

The object of this study is to synthesize Li 3 Ba 2 Gd 3 (MoO 4 ) 8 doped with Eu 3+ ions and prepared with solidstate reaction technology. The results show that the dominant emission peak of Li 3 Ba 2 Gd 3-x (MoO 4 ) 8 :Eu x phosphor is 5 D 0 f 7 F 2 (614 nm). The intensity of the emission from 5 D 0 to 7 F 2 is 3.8 times higher than that of commercial phosphors, ZnS:(Mn 2+ ,Te 2+ ) when the Eu 3+ concentration is x ) 2.4. The CIE chromaticity coordinates of the red emission of the Li 3 Ba 2 Gd 0.6 Eu 2.4 (MoO 4 ) 8 phosphor are (0.67, 0.33), which is the NTSC system standard for red chromaticity. Because there are two regions in the excitation spectra of Li 3 Ba 2 Gd 3 (MoO 4 ) 8 :Eu 3+ phosphor, one is assigned from the charge-transfer state (CTS) band at about 320 nm, and the other is from the intra-4f transitions from 350 to 500 nm. Hence, the phosphors could be strongly excited by near-UV and blue LED in solid-state lighting technology. The analysis of the lifetime, decay curves, and efficiency of the 5 D 0 f 7 F 2 emission indicates the weak energy transfer between Eu 3+ pairs. The temperature dependence PL and absorption spectra study shows that thermal quenching behavior can be attributed to crossover from the 5 D 0 excited state to the CTS band.

Enhanced photoluminescence of Li3Ba2Gd3 (MoO4)8:Eu3+ red phosphor synthesized by mechanochemically assisted direct solid state reaction method at room temperature

“…Recently, the successful preparation and characterisation of the single and pure phase Li 3 Ba 2 Gd 3 (MoO 4 ) 8 :Eu 3? powders were reported by Chang et al [19]. Guo [20] and coworkers reported that Li 3 Ba 2 Ln 3 (MoO 4 ) 8 :Eu 3?…”

Inorganic Phosphor Materials for Lighting

“…As mentioned above, molybdate, tungstate, niobate, and tantalate hosts activated with Eu 3? have been widely investigated [151][152][153][154][155][156][157][158][159][160][161][162][163][164][165][166][167], also exploting co-doping with Sm 3? , but only in a limited number of cases the two strategies described above (high Eu 3?…”

Growth and optical spectroscopy of KPb2Cl5 crystal containing Mn2+

“…The electronic absorption, excitation and emission spectra of Mn 2+ have been extensively investigated in a wide variety of hosts [25][26][27][28][29][30][31][32][33][34]. As far as the emission color of Mn 2+ activated phosphors is concerned, it falls into two classes: those with green emission and those with green-to-red emission [35,36].…”