Application of modified metal-organic frameworks in water treatment

How to ensure water safety and clean water supply is a problem that cannot be ignored in modern industrialized society. However, due to the rapid urbanization, the content of heavy metal ions, antibiotics and organic pollutants in the water have increased. Water pollution has become a global problem. Therefore, how to efficiently carry out water treatment has become an urgent problem to be solved. Metal-organic frameworks (MOFs) are new porous materials with three-dimensional crystal structure, which are composed of metal ions and organic ligands. MOFs have controllable pore size, abundant adsorptive sites, a large number of active sites, so they have great application prospects in the field of water treatment. However, the water stability of general pure MOFs is relatively poor because water molecules attack the coordination bonds between metal ions and organic ligands in MOFs. Based on this theory, by modifying pure MOFs, the binding energy between metal and ligand increases, which can effectively protect the structure of MOFs. In this paper, metal ion modification, polymer modification, inorganic nonmetallic modification and functional group modification of MOFs are reviewed to remove heavy metal ions, antibiotics, and organic pollutants from water.