State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002 China.; College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007 China ; University of the Chinese Academy of Sciences, Beijing 100049 China ; College of Chemistry, Fuzhou University, Fuzhou 350116 China ; Chemical Refining Laboratory, Refining Department, Egyptian Petroleum Research Institute, Nasr City 11727 Egypt
Abstract:
Although porous organic cages (POCs), particularly imine-linked (CN) ones, have advanced significantly over the last few decades, the reversible nature of imine linkages makes them prone to hydrolysis and structural collapse, severely limiting their applications under moist or water conditions. Herein, seven water-stable hydrazone-linked (CN–N) POCs are prepared through a simple coupling of the same supramolecular tetraformylresorcin4]arene cavitand with different dihydrazide linkers. Their structures are all determined by single-crystal X-ray crystallography, demonstrating rich structural diversity from the 2 + 4] lantern, 3 + 6] triangular prism, and unprecedented 4 + 8] square prism to the extra-large 6 + 12] octahedron. In addition, they respectively exhibit tunable window diameters and cavity volumes ranging from about 5.4 to 11.1 nm and 580 to 6800 Å3. Moreover, their application in the water environment for pollutant removal was explored, indicating that they can effectively eliminate various types of contaminants from water, including radionuclide waste, toxic heavy metal ions, and organic micropollutants. This work demonstrates a convenient method for rationally constructing versatile robust POCs and presents their great application potentialities in water medium.A convenient method for constructing water-stable hydrazone-linked porous organic cages (POCs) with tunable structures has been reported, and such POCs can be used as robust adsorbents for effective removal of various pollutants from water.
