Ratiometric Fluorescence Thermometry, Quantitative Gossypol Detection, and CO Chemical Fixation by a Multipurpose Europium (III) Metal-Organic Framework.

A lanthanide-based molecular crystalline material endows metal-organic frameworks (MOFs) with many fascinating applications such as fluorescence detection and CO chemical fixation. Herein, we describe and study a multipurpose europium(III) MOF with the formula of {[Eu(TATAB)]·2.5HO·2DMF} () (where HTATAB is 4,4',4″-((1,3,5-triazine-2,4,6-triyl)tris(azanediyl))tribenzoic acid ligand) for photoluminescence sensor matrix and CO chemical fixation. This features 1D square channels along the c direction with a pore size of ca.14.07 Å × 14.07 Å, occupied by lattice water and DMF molecules. The obtained can achieve simultaneous luminescence of the HTATAB ligand and Eu ions, which can be developed as the sensor matrix for ratiometric fluorescence thermometry. The luminescence of the demonstrates an obvious color change from red to yellow as temperature rises from 303 to 373 K and the has a satisfying relative sensitivity of 3.21% K and a small temperature uncertainty of 0.0093 K at 333 K. Moreover, sensitive detection of gossypol was achieved with a quenching constant of 1.18 × 10 M and a detection limit of 4.61 μM. A combination of the competitive absorption and photoinduced electron transfer caused by host-guest interactions and strengthened π-π packing effect synergistically between gossypol molecules and the skeleton realizes the "turn-off" sensing of gossypol. Importantly, the nature of the allows showing CO chemical fixation under mild conditions. Thus, the can be utilized as a multipurpose material for ratiometric fluorescence thermometry, quantitative gossypol detection, and CO chemical fixation.