Abstract Langbeinite type compounds are a large kind of oxometallate with good flexibility structure. Herein, we synthesized a new langbeinite type compound K2Dy1.5Ta0.5(PO4)3, in which the Dy3+ and Ta5+ were blended to occupy the same crystallographic cites. Simultaneously, solid solutions of K2Dy1.5–xEuxTa0.5(PO4)3 (x = 0–1.5) were prepared and their photoluminescence properties were investigated. Due to energy transfer from Dy3+ to Eu3+, both Dy3+ and Eu3+ characteristic emissions were observed under 393 nm light excitation. The emitting color of K2Dy1.5–xEuxTa0.5(PO4)3 turns from green through yellow to red by simply adjusting the Eu3+ concentration from 0 to 0.4. Moreover, K2Dy1.48Eu0.02Ta0.5(PO4)3 phosphor possesses superior temperature stability of fluorescence, restraining near unique emitting intensity at 150 °C of that at 25 °C. These results manifest that K2Dy1.5–xEuxTa0.5(PO4)3 solutions are promising multi-color emitting phosphors candidate for near-UV LED.

中文翻译：

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朗贝因石型固溶体荧光粉 K2Dy1.5–Eu Ta0.5(PO4)3 的能量转移、优异的热稳定性和多色发光性能

摘要 朗贝因石型化合物是一种大型的金属氧酸盐，具有良好的柔韧性结构。在此，我们合成了一种新的朗贝因石型化合物 K2Dy1.5Ta0.5(PO4)3，其中 Dy3+ 和 Ta5+ 共混占据相同的晶位。同时，制备了 K2Dy1.5–xEuxTa0.5(PO4)3 (x = 0–1.5) 的固溶体并研究了它们的光致发光性能。由于能量从 Dy3+ 转移到 Eu3+，在 393 nm 光激发下观察到 Dy3+ 和 Eu3+ 特征发射。通过简单地将 Eu3+ 浓度从 0 调整到 0.4，K2Dy1.5–xEuxTa0.5(PO4)3 的发光颜色从绿色变为黄色到红色。此外，K2Dy1.48Eu0.02Ta0.5(PO4)3 荧光粉具有优异的荧光温度稳定性，在 150°C 时抑制了接近 25°C 时的独特发射强度。