Rare earth doped fluoride-based up-conversion luminescent materials have been widely studied in non-contact temperature sensing technology. However, the luminous intensity of the fluoride at high temperature still needs to be improved. Here, enhanced up-conversion luminescence and temperature sensing performance of NaBiF: Er, Yb is realized by Al substitution. The samples exhibit the characteristic green (521 nm and 540 nm) and red (654 nm) emissions of Er ion under 980 nm excitation. When the concentration of Al is 5%, the green emission is enhanced by about 10 times, and the red light is enhanced by about 7 times. Obvious lattice shrinkage caused by the introduction of Al is responsible for the enhancement. In addition, the optimal sample is highly thermally stable from 303 K to 443 K. The maximum relative sensitivity at 303 K increases from 0.791% K to 1.106% K. The results indicate that NaBiF: Er, Yb, Al be a potential thermosensitive material.

中文翻译：

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增强 NaBiF4: Er3+、Yb3+、Al3+ 的上转换发光和温度传感性能

稀土掺杂氟化物基上转换发光材料在非接触温度传感技术中得到了广泛的研究。但氟化物在高温下的发光强度仍有待提高。在这里，通过 Al 替代实现了 NaBiF: Er, Yb 增强的上转换发光和温度传感性能。样品在 980 nm 激发下表现出 Er 离子的特征绿光（521 nm 和 540 nm）和红光（654 nm）发射。当Al浓度为5%时，绿光发射增强约10倍，红光增强约7倍。 Al的引入引起的明显晶格收缩是增强效果的原因。此外，最佳样品在303 K至443 K范围内具有高度热稳定性。303 K时的最大相对灵敏度从0.791% K增加至1.106% K。结果表明NaBiF: Er, Yb, Al是一种潜在的热敏材料。