In the fields of fluid dynamics, aeronautical engineering, environment engineering, and energy technology, it is critical to accurately measure the physical parameters of a material surface. [1] Optoelectronic devices have generally been employed as temperature and pressure sensors. [2] However, their sensing area is limited to a single point on a surface. There is a need to measure entire surfaces and obtain multidimensional data for mapping surfaces. There are high expectations that materials for surface measurements, such as temperature and pressure-sensitive dyes, will overcome this intrinsic limitation of optoelectronic devices.We seek to design temperature-sensitive dyes using luminescent lanthanide complexes. Lanthanide complexes exhibit characteristic luminescence with narrow emission bands (full width at half maximum, fwhm < 10 nm) and long emission lifetimes (> 1 ms), [3] which make them suitable for use in sensing devices. In 2003, Amao and co-workers reported the first temperature-sensitive dye that employed an Eu III complex in a polymer film. [4] Khalil et al. demonstrated the high performance of an Eu III complex for a temperature-sensitive paint (temperature sensitivity: 4.42 % 8C À1 ). [5] We have reported a Tb III complex, Tb(hfa) 3 -(H 2 O) 2 (hfa: hexafluoro acetylacetonato), that is suitable as a temperature-sensing probe since it exhibits effective energy back transfer (BEnT) from the emitting level of the Tb III ion to the excited triplet state of the hfa ligand. [6] Since BEnT depends on the energy barrier of the process, the emission intensity varies with temperature.To improve the thermosensing performance, it is necessary to develop a thermostable structure for high-temperature sensing and to implement a dual sensing unit for a high sensing ability. First, we focused on a lanthanide coordination polymer to produce a thermostable structure. Thermally stable coordination polymers and metal-organic frameworks have been widely studied. [7] Carlos and co-workers recently reported novel three-dimensional lanthanide-organic frameworks with 2,5-pyridinedicarboxylic acid. [8] Marchetti et al. developed thermostable Eu III coordination polymers with 4acyl-pyrazolone ligands. [9] Here, we consider that introducing Tb III ion and hfa ligands to coordination polymer frameworks will produce a Tb III coordination polymer that can be used as a temperature-sensing probe. The triplet state of hfa (22 000 cm À1 ) is very close to the emitting level of the Tb III ion (20 500 cm À1 ), resulting in effective EnT1 and BEnT and thus high-performance thermosensing dyes (Figure 1 a). We also selected low-vibrational frequency phosphane oxide [10] as the linking part in the Tb III coordination polymer because lanthanide complexes with high emission quantum yields composed of hfa and bidentate phosphane oxide ligands have been reported. [11] Second, we attempted to impart ratiometric temperature sensing by using luminescent Eu III and Tb III ions in the frameworks of the coordination polymer to realize a high th...

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Novel thermostable organo‐phosphor compounds composed of coordination polymers are reported. Tight‐binding structures with intermolecular interactions of the coordination polymer induce both thermostability (decomposition point >300 °C) and high emission quantum yield (ΦLn=83 %). Their structures (see picture), thermogravimetric analyses, and remarkable photophysical properties are presented for the first time.

GeneralEuropium acetate n-hydrate (99.9%), terbium acetate tetrahydrate (99.9%), gadolinium acetate tetrahydrate (99.9%), 1.55 M n-butyllithium (n-BuLi) in n-hexane, and hydrogen peroxide were purchased from Kanto Chemical Co., Inc. 2,5-Dibromofuran, 3,4-ethylenedioxythiophene, 2,5-dibromothiophene, and chlorodiphenylphosphine (PPh 2 Cl) were obtained from Tokyo Chemical Industry Co., Ltd. All other chemicals and solvents were reagent grade and were used without further purification.