A Supramolecular Organic Framework for Iodine Capture from Vapor and Solution

Due to its high volatility and strong diffusion, iodine poses a serious threat to both the environment and human health, making the development of effective iodine capture materials an urgent priority. In this work, we present a supramolecular organic framework, C1, synthesized from nor-seco-cucurbit[10]uril (ns-Q[10]), p-phenylenediamine (PPD), phenyl-pyridin-2-ylmethylamine (PPN), and [CdCl₄]^2-. The single-crystal structure of C1 was successfully determined by X-ray diffraction. This framework exhibits excellent iodine adsorption performance, with a maximum adsorption capacity of 2.27 g·g^-1 in the vapor phase and a removal efficiency exceeding 95% in both n-hexane and aqueous solutions. The outstanding adsorption performance stems from the abundant amino, carbonyl, and aromatic groups within C1. These groups act as electron-donating sites, facilitating the formation of charge-transfer complexes with iodine and enabling capture through electrostatic interactions. This study not only clarifies the iodine adsorption mechanism within the framework, but also offers strategies for the design of effective and stable iodine adsorption materials.