COMOC - Center for Ordered Materials Organometallics and Catalysis, Department of Chemistry, Ghent University, Krijgslaan 281-S3, Ghent 9000, Belgium.
Toyota Central R&D Laboratories, Inc., Nagakute, Aichi 480-1192, Japan.
ACS Appl Mater Interfaces. 2020 Mar 18;12(11):13540-13550. doi: 10.1021/acsami.0c01470. Epub 2020 Mar 6.
2,2'-Bipyridine is the most widely used chelating ligand for developing metal complexes in coordination and supramolecular chemistry. Here, we present a series of three bipyridine periodic mesoporous organosilicas (BPy-PMOs) grafted with lanthanide β-diketonate complex for the purpose of obtaining thermochromic materials, which can be employed as ratiometric temperature sensors. Such thermometers are based on the ratio of two emission intensity peaks and are not affected by factors such as alignment or optoelectronic drift of the excitation source and detectors. Three thermometric systems are studied: Dy-Dy, Tb-Sm, and Tb-Eu with the first two showing very attractive performance. For the first two systems, some of the best reported to date relative sensitivities are observed. In the BPy-PMO@Dy(acac) system, it is very unusual that the I→ H transition is already occupied at low temperature such as 200 K, which influences its thermometric behavior. The Tb-Sm shows excellent performance in the physiological range and when suspended in water. We have additionally confirmed that the BPy-PMO hybrid materials lack toxicity to human cells, proving them very promising candidates for biomedical thermometric applications.
2,2'-联吡啶是配位和超分子化学中用于开发金属配合物的最广泛使用的螯合配体。在这里，我们提出了一系列接枝有镧系β-二酮配合物的三联吡啶周期性介孔有机硅（BPy-PMO），旨在获得热致变色材料，可用作比率型温度传感器。这些温度计基于两个发射强度峰的比值，不受激发源和探测器的对准或光电漂移等因素的影响。研究了三种测温系统：Dy-Dy、Tb-Sm 和 Tb-Eu，前两个系统表现出非常有吸引力的性能。对于前两个系统，观察到了迄今为止一些报道中最好的相对灵敏度。在 BPy-PMO@Dy(acac)系统中，非常不寻常的是 I→H 跃迁在 200 K 等低温下已经被占据，这影响了其测温行为。Tb-Sm 在生理范围内和悬浮在水中时表现出优异的性能。我们还证实，BPy-PMO 杂化材料对人体细胞没有毒性，证明它们非常有希望用于生物医学测温应用。
