NH_(2)-MIL-53(Al)对氟离子的同时去除和检测

NH_(2)-MIL-53(Al)for Simultaneous Removal and Detection of Fluoride Anions

本文通过一种简单溶剂热法制备了氨基功能化的金属有机框架材料NH_(2)-MIL-53(Al),可用于同时去除和检测氟.结果表明,NH_(2)-MIL-53(Al)对氟具有较强的捕获能力(202.5 mg/g)和较快的吸附速率,在15分钟内能将5 ppm的氟降低至饮用水标准下.更为重要的是,氟离子和NH_(2)-MIL-53(Al)之间的特异性结合促使荧光配体NH_(2)-BDC释放,有利于通过与浓度相关的荧光增强效应实现对氟离子的检测.同时,NH_(2)-MIL-53(Al)传感器具有检测范围宽(0.5〜100μmol/L)、选择性好和检测灵敏度高(检测限为0.31μmol/L)等特点.该传感器对实际水体中的氟检测具有理想的加标回收率(从89.6%到116.1%),进一步证明了其对实际含氟污水监测的可行性.

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 NH2-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 0.31μmol/L)toward fluoride accompanied with a wide response interval(0.5-100μmol/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.