Multivariate Metal–Organic Frameworks for the Simultaneous Capture of Organic and Inorganic Contaminants from Water

Abstract

We report a new water-stable multivariate (MTV) metal–organic framework (MOF) prepared by combining two different oxamide-based metalloligands derived from the natural amino acids l -serine and l -methionine. This unique material features hexagonal channels decorated with two types of flexible and functional “arms” (−CH 2 OH and −CH 2 CH 2 SCH 3 ) capable of enabling, synergistically, the simultaneous and efficient removal of both inorganic (heavy metals such as Hg 2+, Pb 2+, and Tl + ) and organic (dyes such as Pyronin Y, Auramine O, Brilliant green, and Methylene blue) contaminants, and, in addition, this MTV-MOF is completely reusable. Single-crystal X-ray diffraction measurements allowed solving the crystal structure of a host–guest adsorbate, containing both HgCl 2 and Methylene blue, and offered unprecedented snapshots of this unique dual capture process. This is the very first time that a MOF can be used for the removal of all sorts of pollutants from water resources, thus opening new perspectives for this emerging type of MTV-MOF.