Linkage Design in Two-Dimensional Covalent Organic Frameworks for High Iodine Uptake

Abstract

Radioactive iodine waste in the nuclear field is harmful to the environment and human health. Covalent organic frameworks (COFs) are a novel kind of porous organic material with a well-fine and unformal structure, which is an excellent candidate as a solid adsorbent for iodine adsorption. Herein, a linkage design is proposed for effective iodine adsorption. Imine-linkage COF (I-COF) and hydrazone-linked COF (H-COF) are constructed under solvothermal conditions. The Brunauer–Emmett–Teller surface area of H-COF is as high as 1747 m2 g−1. Furthermore, the H-COF shows high porosity, stability, and rich atoms in the linkage. As a result, the work outperforms most of the previous reports in iodine capture with a high capture value at 5.72 g g−1.