Abstract Novel blue emitting thulium doped La2(MoO4)3 nanophosphors were synthesized by facile co-precipitation method and the spectroscopic features were systematically studied on the basis of Judd-Ofelt analysis. The tetragonal phase formation of Tm3+ doped La2(MoO4)3 with space group I41/a is confirmed from the XRD analysis and the growth mechanism by oriented attachment is revealed by TEM analysis. The 1D2→3F4 transition at 453 nm is the dominant emission peak of Tm3+ in the photoluminescence emission spectra and offers major contribution towards the intense blue emission of the phosphor material. The Judd-Ofelt intensity parameters exhibit the trend Ω 2 > Ω 4 > Ω 6 , which point out the asymmetric site occupancy of Tm3+ ions in the host matrix. The estimated higher branching ratio for 1D2→3F4 blue emission of Tm3+ signifies it as a potential laser emission transition. The CIE chromaticity co-ordinates of optimized La1.94Tm0.06(MoO4)3 nanophosphors falls in the blue region of the chromaticity diagram with co-ordinates (0.214,0.097).

中文翻译：

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新型蓝色发光 Tm3+ 活化钼酸镧：发光行为研究和 Judd-Ofelt 理论分析

摘要 采用简便的共沉淀法合成了新型蓝色发光铥掺杂的La2(MoO4)3纳米荧光粉，并在Judd-Ofelt分析的基础上系统地研究了其光谱特征。XRD 分析证实了 Tm3+ 掺杂的 La2(MoO4)3 的四方相形成，空间群为 I41/a，TEM 分析揭示了定向附着的生长机制。453 nm 处的 1D2→3F4 跃迁是光致发光发射光谱中 Tm3+ 的主要发射峰，并且对磷光体材料的强蓝色发射做出了主要贡献。Judd-Ofelt 强度参数表现出趋势 Ω 2 > Ω 4 > Ω 6 ，这表明 Tm3+ 离子在宿主基质中的不对称位点占有率。Tm3+ 的 1D2→3F4 蓝色发射估计更高的分支比表明它是潜在的激光发射跃迁。优化的 La1.94Tm0.06(MoO4)3 纳米磷光体的 CIE 色度坐标落在色度图的蓝色区域，坐标为 (0.214,0.097)。