Multi-layer active interface construction with polyphenols and nano-silver on nano collagen fiber for efficient capturing iodine vapor

How to construct active sites with specific affinity for radioactive iodine has always been an important research direction to solve iodine pollution. In this study, a multi-layer active interface constructed with bayberry tannin and nano-silver based on collagen fiber (Ag0@BT-nCF) was prepared with high-efficiency adsorption properties for iodine. With a series of characterization methods, the bayberry tannin was fixed on the nCF to construct the first layer of iodine-active interface with polyhydroxyl. And, the second layer of iodine-active nano silver particles is constructed through the chelation of silver with the carboxyl group of collagen and hydroxyl group of bayberry tannin. The iodine capture results showed that the Ag0@BT-nCF exhibited significantly higher iodine adsorption performance (1,704 mg/g) compared with other adsorbents. Mechanism analysis showed that Ag0 and iodine vapor mainly react chemically to form AgI. Secondly, the –OH, –CONH2 and –NH on the surface of the BT-nCF also participated in chemical adsorption. In addition, within a certain temperature range, Ag0@BT-nCF shows excellent stability after capturing iodine, which can effectively prevent the volatilization and escape of iodine. Therefore, the as-prepared Ag0@BT-nCF provides a new reference for the removal of radioactive iodine as an efficient adsorption material.