NH<sub>2</sub>‑MIL-53(Al) Metal–Organic Framework as the Smart Platform for Simultaneous High-Performance Detection and Removal of Hg<sup>2+</sup> ZhangLiang WangJing DuTing ZhangWentao ZhuWenxin YangChengyuan YueTianli SunJing LiTao WangJianlong 2019 The worsening pollution due to mercury species makes it inevitable to explore prospective versatile materials, which not only can detect mercury ions (Hg<sup>2+</sup>) with high sensitivity but also possesses efficient capture and removal ability. In this study, a series of classic organic ligand-based luminescence MOFs materials with high oxidation state central metals (Al<sup>3+</sup>, Zr<sup>4+</sup>, Cr<sup>3+</sup>, Fe<sup>3+</sup>, and Ti<sup>4+</sup>) were synthesized and were screened to achieve simultaneously Hg<sup>2+</sup> detection and removal through the strong coordination of amino groups or nitrogen centers with Hg<sup>2+</sup> and the intrinsic fluorescence intensity of MOFs regulated by the ligand-to-metal charge transfer (LMCT) effect. Among these checked materials, NH<sub>2</sub>-MIL-53­(Al) exhibited the excellent ability for Hg<sup>2+</sup> detection with wide response interval (1–17.3 μM), low detection limit (0.15 μM), good selectivity, wide pH adaptation (4.0–10.0), and strong anti-interference ability. Meanwhile, the resultant NH<sub>2</sub>-MIL-53­(Al) possessed an efficient removal capability toward Hg<sup>2+</sup>, accompanied by a fast uptake kinetics (within 60 min) and large loading capacity (153.85 mg g<sup>–1</sup>). Furthermore, NH<sub>2</sub>-MIL-53­(Al) also displayed satisfactory stability before and after Hg<sup>2+</sup> treatment because of the formation of strong coordination bonds between high oxidation state aluminum (Al<sup>3+</sup>) and organic carboxylate ligands. Notably, the prepared NH<sub>2</sub>-MIL-53­(Al) had no significant loss of adsorption performance even after being reused four times. All of these superior properties render the smart NH<sub>2</sub>-MIL-53­(Al) nanohexahedron a great potential for simultaneous Hg<sup>2+</sup> detection and removal from water.