Flexible interdigitated layered framework with multiple accessible active sites for high-performance CH_(3)I capture  

作　　者：Bo Tai Baoyu Li Linwei He Zhonglin Ma Shujing Lin Mingxing Zhang Junchang Chen Fuqi Wu Long Chen Xing Dai Fuyin Ma Zhifang Chai Shuao Wang 

机构地区：[1]State Key Laboratory of Radiation Medicine and Protection,School for Radiological and interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions,Soochow University,Suzhou 215123,China

出　　处：《Science China Chemistry》2024年第5期1569-1577,共9页中国科学（化学英文版）

基　　金：supported by the Intergovernmental International Cooperation of the National Key R&D Program of China(2022YFE0105300);the National Natural Science Foundation of China(21790374, 22276130, 22176139, 21825601);the New Cornerstone Science Foundation through the XPLORER PRIZE。

摘　　要：The development of adsorbent materials for effective capture of radioactive iodomethane(CH_(3)I) from the off-gas of used nuclear fuel reprocessing, remains a significant and challenging line of research because currently state-of-art adsorbents still suffer from low binding affinity with CH_(3)I. Here, we proposed a brand-new adsorption topological structure by developing a 2D interdigitated layered framework, named SCU-20, featuring slide-like channel with multiple active sites for CH_(3)I capture. The responsive rotating-adaptive aperture of SCU-20 enables the optimal utilization of all active sites within the pore for highly selective recognition and capture of CH_(3)I. A record-breaking CH_(3)I uptake capacity of 1.84 g/g was achieved under static sorption conditions with saturated CH_(3)I vapor. Both experimental and theoretical findings demonstrated that the exceptional uptake of SCU-20 towards CH_(3)I can be attributed to the confined physical electrostatic adsorption of F sites, coupled with the chemical nitrogen methylation reaction with uncoordinated N atoms of pyrazine. Moreover, dynamic CH_(3)I uptake capacity potentially allows for the capture of CH_(3)I in simulated real-world off gas reprocessing conditions. This study highlights the potential of SCU-20 as a promising candidate for efficient capture of iodine species and contributes to the development of effective solutions for radioactive iodine remediation.

关 键 词：2D interdigitated layered framework IODOMETHANE dual-sites electrostatic interaction physisorption and chemisorption 

分 类 号：X771[环境科学与工程—环境工程] TQ424[化学工程]