Europium-activated calcium oxide (CaO: Eu) phosphor shows great potential in the fabrication of light-emitting diodes (LEDs). However, its luminescent intensity and thermostability still need to be further enhanced. In this work, the photoluminescence property and thermostability of CaO: Eu^2+/3+ were improved significantly by codoping a few of Cl^– ions into it. Compared with CaO: Eu^2+/3+ samples, CaO: Eu^2+/3+, Cl^– phosphors not only have tunable luminescence but also show stronger luminescence intensity and thermal stability. The emission color of phosphors can be tuned by changing the excitation wavelength; typically, strong red/blue light can be displayed under 250/362 nm excitation. More importantly, both the red and blue emissions will increase simultaneously with increasing codoped Cl^– content. When the Cl^– ion content is 0.06, the emission intensity of CaO: 0.01Eu^2+/3+, 0.06Cl^– reaches its maximum and its red and blue emission intensities increase by approximate 2.5 times and 13.2 times, respectively. The results show that CaO: Eu^2+/3+, Cl^– phosphors have potential application value in LEDs and anti-counterfeiting.

中文翻译：

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通过共掺杂 Cl– 离子实现 CaO：Eu2+/3+ 荧光粉的可调光学特性、增强的光致发光和热稳定性


铕活化氧化钙 （CaO： Eu） 荧光粉在制造发光二极管 （LED） 方面显示出巨大潜力。然而，其发光强度和热稳定性仍需进一步提高。在这项工作中，通过将少量 Cl^– 离子共掺杂，显著提高了 CaO：Eu^2+/3+ 的光致发光性能和热稳定性。与 CaO：Eu^2+/3+ 样品相比，CaO：Eu^2+/3+、Cl^– 荧光粉不仅具有可调的发光，而且表现出更强的发光强度和热稳定性。荧光粉的发射颜色可以通过改变激发波长来调整;通常，在 250/362 nm 激发下可以显示强红/蓝光。更重要的是，红色和蓝色发射将随着共掺杂 Cl^– 含量的增加而同时增加。当 Cl^– 离子含量为 0.06 时，CaO：0.01Eu^2+/3+、0.06Cl^– 的发射强度达到最大值，其红蓝发射强度分别增加了约 2.5 倍和 13.2 倍。结果表明，CaO： Eu^2+/3+， Cl^– 荧光粉在 LED 和防伪方面具有潜在的应用价值。