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.

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Phosphors of LaAlGe 2 O 7 doped with Tm 3+ and Er 3+ of high color purity, exhibiting a narrow band emission in the blue and green regions, were obtained. ͑La 1−x Ln x ͒AlGe 2 O 7 ͑Ln= Tm, Er͒ powders are bright emitters, with chromaticity color coordinates that are comparable to or better than those of standard phosphors for display or lighting devices. The blue emission of the Tm 3+-doped phosphor had CIE chromaticity coordinates ͑0.151, 0.033͒ with a dominant wavelength of 455 nm and a color purity of 94%. The Er 3+-doped phosphor had color coordinates ͑0.249, 0.718͒, a dominant wavelength of 542 nm, and 92% purity.