NH _\textbf2 -MIL-53(Al) for Simultaneous Removal and Detection of Fluoride Anions

To address the limitations of the separate fluoride removal or detection in the existing materials, herein, amino-decorated metal organic frameworks NH _2 -MIL-53(Al) have been succinctly fabricated by a sol-hydrothermal method for simultaneous removal and determination of fluoride. As a consequence, the proposed NH _2 -MIL-53(Al) features high uptake capacity (202.5 mg/g) as well as fast adsorption rate, being capable of treating 5 ppm of fluoride solution to below the permitted threshold in drinking water within 15 min. Specifically, the specific binding between fluoride and NH _2 -MIL-53(Al) results in the release of fluorescent ligand NH _2 -BDC, conducive to the determination of fluoride via a concentration-dependent fluorescence enhancement effect. As expected, the resulting NH _2 -MIL-53(Al) sensor exhibits selective and sensitive detection (with the detection limit of 0.31 \mu mol/L) toward fluoride accompanied with a wide response interval (0.5-100 \mu mol/L). More importantly, the developed sensor can be utilized for fluoride detection in practical water systems with satisfying recoveries from 89.6% to 116.1%, confirming its feasibility in monitoring the practical fluoride-contaminated waters.