Department of Physics and Interdisciplinary Program of Biomedical, Mechanical & Electrical Engineering, Pukyong National University, Busan, 608-737, Republic of Korea.
College of Electronic Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing, 210046, People's Republic of China.
Sci Rep. 2017 Jul 20;7(1):6023. doi: 10.1038/s41598-017-06421-7.
Optical thermometry based on the up-conversion intensity ratio of thermally coupled levels of rare earth ions has been widely studied to achieve an inaccessible temperature measurement in submicron scale. In this work, a novel optical temperature sensing strategy based on the energy transfer from charge transfer bands of W-O and Eu-O to Eu-Dy ions is proposed. A series of Eu/Dy co-doped SrWO is synthesized by the conventional high-temperature solid-state method. It is found that the emission spectra, emission intensity ratio of Dy (572 nm) and Eu (615 nm), fluorescence color, lifetime decay curves of Dy (572 nm) and Eu (615 nm), and relative and absolute sensitivities of Eu/Dy co-doped SrWO are temperature dependent under the 266 nm excitation in the temperature range from 11 K to 529 K. The emission intensity ratio of Dy (572 nm) and Eu (615 nm) ions exhibits exponentially relation to the temperature due to the different energy transfer from the charge transfer bands of W-O and Eu-O to Dy and Eu ions. In this host, the maximum relative sensitivity S can be reached at 1.71% K, being higher than those previously reported material. It opens a new route to obtain optical thermometry with high sensitivity through using down-conversion fluorescence under ultraviolet excitation.
基于稀土离子热耦合能级的上转换强度比的光学测温技术已经被广泛研究，以实现亚微米尺度上无法触及的温度测量。在这项工作中，提出了一种基于 W-O 和 Eu-O 的电荷转移带到 Eu-Dy 离子的能量转移的新型光学温度传感策略。通过传统的高温固态法合成了一系列 Eu/Dy 共掺杂 SrWO。研究发现，在 266nm 激发下，在 11K 至 529K 的温度范围内，Dy（572nm）和 Eu（615nm）的发射光谱、Dy（572nm）和 Eu（615nm）的发射强度比、荧光颜色、Dy（572nm）和 Eu（615nm）的荧光寿命衰减曲线以及 SrWO 中 Eu/Dy 共掺杂的相对和绝对灵敏度均随温度变化而变化。由于 W-O 和 Eu-O 的电荷转移带到 Dy 和 Eu 离子的不同能量转移，Dy（572nm）和 Eu（615nm）离子的发射强度比与温度呈指数关系。在该基质中，最大相对灵敏度 S 可达到 1.71%K，高于以前报道的材料。它为通过使用紫外激发下的下转换荧光获得高灵敏度的光学测温开辟了一条新途径。
