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Various novel SrBi2Ta2O9:Tm3+ blue-emitting materials were achieved via solid-state synthesis. The structure and phase purity of prepared SrBi2Ta2O9:xTm3+ (x = 0.005-0.30 mol) were examined by X-ray powder diffraction. The surface morphology of SrBi2Ta2O9:0.01Tm3+ were studied by scanning electron microscopy. Photoluminescence properties were systematically explored under the monitoring emission (λem = 468 nm) and excitation (λex = 303 nm) spectra. The optimum mole ratio of as-synthesized phosphors was 0.01 mol. The concentration quenching mechanism in the SrBi2Ta2O9 host was due to electric multipole interaction. Particularly, the chromaticity coordinates (0.1334, 0.0474) of SrBi2Ta2O9:0.01Tm3+ are near to those of the commercial BaMgAl10O17:Eu2+. These results validated the SrBi2Ta2O9:Tm3+ phosphor can be utilized good blue-emitting candidate for W-LEDs.

A series of Ca2YTaO6: Tm3+ blue-emitting phosphors were firstly prepared by the solid-state method. The phase formations and purity of Ca2YTaO6: xTm3+ (x = 0.3%-5% mol) were verified by X-ray powder diffraction. The morphological characteristics of Ca2YTaO6: 0.005Tm3+ were detected by scanning electron microscopy (SEM). Photoluminescence properties were discussed by emission (λem = 460 nm) and excitation (λex = 359 nm) spectra. The critical doping concentration of the products was 0.005 mol. The proposed concentration quenching mechanism in Ca2YTaO6 materials was the electric multipole interaction. Besides, the color coordinates (0.1408, 0.0891) of Ca2YTaO6: 0.005Tm3+ were located in blue region. The results suggested the Ca2YTaO6: Tm3+ phosphors can be promising blue-emitting components for the WLED applications.

Various novel Ba2Y3(SiO4)3F:Tm3+ blue-emitting fluorosilicate materials were achieved via solid-state synthesis. The structure and phase purity of prepared Ba2Y3(SiO4)3F:xTm3+ (x = 0.001-0.10 mol) were examined by X-ray powder diffraction. The surface morphology of Ba2Y3(SiO4)3F:0.01Tm3+ was studied by scanning electron microscopy. Photoluminescence properties were systematically explored under the monitoring emission (λem = 468 nm) and excitation (λex = 302 nm) spectra. The optimum mole ratio of as-synthesized phosphors was 0.01 mol. The concentration quenching mechanism in the Ba2Y3(SiO4)3F host was due to electric multipole interaction. Particularly, the chromaticity coordinates (0.1334, 0.0474) of Ba2Y3(SiO4)3F:0.01Tm3+ are near to those of the commercial BaMgAl10O17:Eu2+. These results validated the Ba2Y3(SiO4)3F:Tm3+ fluorosilicate phosphor can be used as a good blue-emitting candidate for W-LEDs.

Various novel Ca2MgTeO6:Tm3+ blue-emitting tellurate materials were synthesized via solid-state reaction. The structure and phase purity of prepared Ca2MgTeO6:xTm3+ (x = 0.0025-0.10 mol) were examined by X-ray powder diffraction. The Ca2MgTeO6:Tm3+ phosphors emit blue emission at 359 nm excitation. The optimum doping concentration was 0.02 mol. The concentration quenching mechanism in the Ca2MgTeO6 host was due to the electric dipole-dipole interaction. The The CIE chromaticity coordinates of Ca2MgTeO6:Tm3+ phosphors located in the blue region. These results validated the Ca2MgTeO6:Tm3+ tellurate phosphor can be used as good blue-emitting candidate for W-LEDs.

A series of novel Dy3+ activated aluminate Ba2Y1-xDyxAlO5 (x = 0.01–0.30) red-emitting phosphors were synthesized through a high-temperature solid-state route at 1380°C. The X-ray diffraction patterns revealed that the samples were well crystallized in the space group P21/c (No. 14). The spectrum analysis revealed that under UV light excitation, Ba2YAlO5:Dy3+ phosphor exhibited blue and yellow peaks corresponding to 4F9/2–6H15/2 transition and 4F9/2–6H13/2 transition, respectively. The optimum dopant concentration of Dy3+ ions is around 2 mol% and the critical transfer distance of Dy3+ is calculated as 29 Å. The concentration quenching mechanism between Dy3+ has been investigated. Results indicate that Ba2YAlO5:Dy3+ offers the excellent optical properties as a potential yellow-emitting phosphor candidate for n-UV LEDs.