Singh Sachin, Kachhap Santosh, Sharma Manisha, Singh Sunil Kumar
Department of Physics, Indian Institute of Technology (Banaras Hindu University) Varanasi-221005 India
RSC Adv. 2023 May 16;13(22):14991-15000. doi: 10.1039/d3ra02929h. eCollection 2023 May 15.
We demonstrate an enhancement in the upconversion (UC) emission and temperature sensing property of a CaMoO:Er/Yb phosphor distortion of the local symmetry environments and reduction in no-radiative channels. Bi ion co-doping creates a local distortion while the average tetragonal structure of CaMoO remains intact. This creates asymmetry around the Er ions which improves the UC emission. Furthermore, our calculations on XRD data show a reduction in the dislocation density and the micro-strain in the crystal with the introduction of Bi, which also favours the enhancement of UC emission as it reduces the non-radiative channels. Furthermore, the effect of this enhancement on the temperature sensing property of Er ion has also been revealed. Our results show that the UC emission is enhanced about 25 times for Bi co-doped samples which improves the temperature sensitivity significantly. The samples, both with and without Bi co-doping, exhibited relative sensitivities of 0.0068 K at 300 K and 0.0057 K at 298 K which is a significant improvement and indicates the potential of the material for temperature sensing applications. This proof-of-concept provides a deeper understanding of the effect of Bi doping on UC emission and opens new avenues for the development of high-performance temperature sensing materials.
我们证明了CaMoO:Er/Yb荧光粉的上转换（UC）发射和温度传感特性得到增强，这归因于局部对称环境的畸变和无辐射通道的减少。Bi离子共掺杂产生局部畸变，而CaMoO的平均四方结构保持完整。这在Er离子周围产生不对称性，从而改善了UC发射。此外，我们对XRD数据的计算表明，随着Bi的引入，晶体中的位错密度和微应变降低，这也有利于UC发射的增强，因为它减少了无辐射通道。此外，还揭示了这种增强对Er离子温度传感特性的影响。我们的结果表明，Bi共掺杂样品的UC发射增强了约25倍，这显著提高了温度灵敏度。有无Bi共掺杂的样品在300 K时的相对灵敏度为0.0068 K，在298 K时为0.0057 K，这是一个显著的改进，表明该材料在温度传感应用中的潜力。这一概念验证提供了对Bi掺杂对UC发射影响的更深入理解，并为高性能温度传感材料的开发开辟了新途径。
