Post-synthetic modification on metal organic frameworks composite for efficient removal and sensitive detection of mercury ions in water

Abstract

Post-synthetic modification (PSM) technique is employed on the optimization of metal organic frameworks (MOFs) composites. In this work, a new Zr-MOF derived from UiO-66 is prepared and used as efficient adsorbents for mercury removal from water and able to detect mercury ions with excellent selectivity. It is observed that the fluorescence intensity of UiO-66-An exhibits good linearity across the concentration range of 0.5–2.5 μM and the detection limit of mercury is calculated to be as low as 2.67 × 10-8 M which is below the effluent standard declared by WHO. Furthermore, the removal efficiency of UiO-66-An for Hg (II) can still maintain 64.8 % after 5 cycles of adsorption–desorption process. In addition, the adsorption capacity of the adsorbent is determined to be as high as 303.03 mg/g for mercury, indicating the successful integration of adsorptive and detective functions together on a single adsorbent material which is beneficial for practical application in mercury management.