Steinegger Andreas, Borisov Sergey M
Graz University of Technology, Institute of Analytical Chemistry and Food Chemistry, Stremayrgasse 9, 8010 Graz, Austria.
ACS Omega. 2020 Mar 30;5(13):7729-7737. doi: 10.1021/acsomega.0c01062. eCollection 2020 Apr 7.
Thermally activated delayed fluorescence (TADF) is a highly temperature-dependent process and can be used in optical thermometry. TADF-based optical thermometers reported so far show fairly high-temperature sensitivity but have poor brightness and significant oxygen cross-talk. A new class of TADF emitters, Zn(II) Schiff base complexes, possess excellent brightness and high temperature sensitivity of the decay time at ambient temperature (4.1%/K change of TADF lifetime at 25 °C), enabling a resolution better than 0.03 °C. Oxygen cross-sensitivity is eliminated by covering the sensing layer (luminophore in polystyrene) with an off-stoichiometry thiol-ene polymer as an oxygen-consuming layer, and a poly(vinylidene chloride--acrylonitrile) layer as an oxygen barrier. The material is stable after more than 2 months of storage at ambient air, which enables long-term temperature monitoring.
热激活延迟荧光（TADF）是一个高度依赖温度的过程，可用于光学测温。迄今为止报道的基于TADF的光学温度计显示出相当高的温度灵敏度，但亮度较差且存在显著的氧串扰。一类新型的TADF发射体，即锌（II）席夫碱配合物，具有出色的亮度以及在环境温度下对衰减时间的高温度灵敏度（25℃时TADF寿命的变化为4.1%/K），分辨率优于0.03℃。通过用非化学计量的硫醇-烯聚合物作为耗氧层以及聚（偏二氯乙烯-丙烯腈）层作为氧阻挡层覆盖传感层（聚苯乙烯中的发光体），消除了氧交叉敏感性。该材料在环境空气中储存两个多月后仍保持稳定，这使得能够进行长期温度监测。
