A Highly Stable Yttrium Organic Framework as a Host for Optical Thermometry and D2O Detection

The yttrium organic framework (Y0.89Tb0.10Eu0.01)(6)(BDC)(7)(OH)(4)(H2O)(4) (BDC=benzene-1,4-dicarboxylate) is hydrothermally stable up to at least 513 K and thermally stable in air in excess of 673 K. The relative intensities of luminescence of Tb3+ and Eu3+ are governed by Tb3+-to-Eu3+ phonon-assisted energy transfer and Tb3+-to-ligand back transfer and are responsible for the differing temperature-dependent luminescence of the two ions. This provides a ratiometric luminescent thermometer in the 288-573 K temperature range, not previously seen for MOF materials, with a high sensitivity, 1.69 +/- 0.04 % K-1 at 523 K. In aqueous conditions, loosely bound H2O can be replaced by D2O in the same material, which modifies decay lifetimes to yield a quantitative luminescent D2O sensor with a useful sensitivity for practical application.

Automated summary

The yttrium organic framework is stable under hydrothermal and air conditions, and can be used as a ratiometric luminescent thermometer and a D2O sensor with high sensitivity.