Abstract The development of Eu3+-doped red phosphors with high absorption in near UV region is of great significance for application in warm white LEDs and remains a tremendous challenge owing to the special electronic structure of rare earth ions. In the present work, a novel BaBi2(MoO4)4:Eu3+ red phosphor were prepared, which exhibits high purity red emission with broad excitation band ranging from 200 to 400 nm, and have a high absorption. Raman analysis and DFT calculations certified that the broad excitation band originated from the characteristic transition absorption of Bi3+ ions. The optimum doping concentration of Eu3+ ions in BaBi2(MoO4)4 was determined to be as high as 50%. The luminescence intensity of BaBi2(MoO4)4:Eu3+ is much higher than that of commercial Y2O3:Eu3+ either under 365 nm or 395 nm excitation. More importantly, the covalence degree has a greater impact on the intensity ratio of electric dipole transition 5D0-7F2 and the magnetic dipole transition 5D0-7F1 (abbreviated as R/O) than the local symmetry around Eu3+ sites. This work presents a strategy to develop high-performance Eu3+-doped red phosphors with high absorption and brightness and provide a reference in exploring other rare earth doped phosphors.

中文翻译：

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Bi3+ 在 Eu3+ 中诱导宽的 NUV 激发带 - 具有白钨矿相关结构的掺杂红色磷光体

摘要 开发在近紫外区具有高吸收率的掺Eu3+红色荧光粉对于暖白光LED的应用具有重要意义，但由于稀土离子的特殊电子结构，仍是一个巨大的挑战。在目前的工作中，制备了一种新型 BaBi2(MoO4)4:Eu3+ 红色荧光粉，其具有高纯度的红色发射，激发波段范围为 200 至 400 nm，并具有高吸收。拉曼分析和 DFT 计算证明宽激发带源自 Bi3+ 离子的特征跃迁吸收。BaBi2(MoO4)4 中 Eu3+ 离子的最佳掺杂浓度被确定为高达 50%。BaBi2(MoO4)4:Eu3+ 在 365 nm 或 395 nm 激发下的发光强度远高于商业 Y2O3:Eu3+。更重要的是，与Eu3+位点周围的局部对称性相比，共价度对电偶极跃迁5D0-7F2和磁偶极跃迁5D0-7F1（简称R/O）的强度​​比的影响更大。这项工作提出了一种开发具有高吸收率和亮度的高性能 Eu3+ 掺杂红色荧光粉的策略，并为探索其他稀土掺杂荧光粉提供参考。