Miao Juhong, Chen Mingyuan, Chen Zichen, Zhang Lei, Wei Song, Yang Xinye
Appl Opt. 2021 Feb 20;60(6):1508-1514. doi: 10.1364/AO.412313.
:, upconversion (UC) micro-crystals with a tetragonal structure were fabricated through a modified sol-gel method. The samples are found to be spherical in shape with a diameter of about 300 nm. Upon excitation of 980 nm light, the UC emission spectra of the phosphors exhibit green and red bands corresponding to the characteristic transitions of ions. As concentration rises, the green emission intensity increases and reaches the maximum at 2.0% content, while the ratio of green/red emission intensities (/) declines monotonically. Temperature sensing capability was studied employing the fluorescent intensity ratio technique from the thermally coupled levels and of in temperature range of 293∼533 K. It is interesting to find that concentration has influence on the absolute sensitivity , while the relative sensitivity is almost independent of content. Furthermore, excellent thermal stability and high temperature sensitivity is also demonstrated in the 2.0% -doped sample with the obtained maximum and as high as 0.008 and 1.093, respectively. The experimental results indicate that / co-doped phosphors can be excellent candidates for temperature sensing applications.
通过改进的溶胶 - 凝胶法制备了具有四方结构的上转换（UC）微晶。发现样品呈球形，直径约为300nm。在980nm光激发下，磷光体的上转换发射光谱呈现出对应于离子特征跃迁的绿色和红色波段。随着浓度的增加，绿色发射强度增加，并在2.0％含量时达到最大值，而绿色/红色发射强度比（/）单调下降。在293∼533K的温度范围内，采用来自热耦合能级和的荧光强度比技术研究了温度传感能力。有趣的是发现浓度对绝对灵敏度有影响，而相对灵敏度几乎与含量无关。此外，在2.0％掺杂的样品中也表现出优异的热稳定性和高温灵敏度，获得的最大值分别高达0.008和1.093。实验结果表明，/共掺杂的磷光体可以是温度传感应用的优异候选材料。
