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A series of red emitting ZnTiO_3 phosphors co-doped with Eu~(3+) and alkali metal ions(Li~+, Na~+ and K~+) was prepared by sol-gel method. The crystal structure of the phosphors was investigated by using X-ray diffraction(XRD) and transmission electron microscopy(TEM) after annealing at 700 ℃. The results show that the crystal structure belongs to the hexagonal phase of ZnTiO_3 with space group R-3:R. The influence of site occupancy of different alkali metal ions on the emission of ZnTiO_3:Eu~(3+) phosphors was investigated in detail. The emission intensity was significantly enhanced by introducing alkali metal ions. In contrast to Eu~(3+) singly doped ZnTiO_3, the red emission intensities of ZnTiO_3:Eu~(3+) with 4 mol% alkali metal ions(Li~+, Na~+, K~+) were enhanced by about 2.1, 1.7 and 1.4 times, respectively. In addition, the Commission Internationale Ed I’eclairage(CIE) chromaticity coordinates of ZnTiO_3:Eu~(3+), Li~+(0.672, 0.328) are quite similar to the National Television Standard Committee(NTSC) standard values for the red(0.670, 0.380).
A series of red emitting ZnTiO 3 phosphors co-doped with Eu ~ (3+) and alkali metal ions (Li ~ +, Na ~ + and K ~ +) was prepared by sol-gel method by using X-ray diffraction (XRD) and transmission electron microscopy (TEM) after annealing at 700 ° C. The results show that the crystal structure belongs to the hexagonal phase of ZnTiO 3 with space group R-3: R. The influence of site occupancy of different alkali metal ions on the emission of ZnTiO_3: Eu ~ (3+) phosphors was investigated in detail. The emission intensity was significantly enhanced by introducing an alkali metal ions. In contrast to Eu ~ (3+) singly doped ZnTiO_3, the red emission intensities of ZnTiO_3: Eu ~ (3+) with 4 mol% of alkali metal ions (Li ~ +, Na ~ +, K ~ +) were enhanced by about 2.1, 1.7 and 1.4 times, respectively. Ed I’eclairage (CIE) chromaticity coordinates of ZnTiO_3: Eu ~ (3+), Li ~ + (0.672, 0.328) are quite similar to the National Television Standard Committee (NTSC) standard values for the red (0.670, 0.380).