Guest Molecules Containing Rich-electron Group Incorporation into Zn-based MOF for the Enhancement of Iodine Uptake

Radioactive iodine capture is a major concern for nuclear power generation and environmental protection. Many metal-organic frameworks (MOFs) have been designed and synthesized to adsorb iodine from vapor or solution, but most of them exhibited unsatisfactory iodine uptake performance because of the insufficiency of adsorption sites. Herein, we chose 1-vinyl-3-ethylimidazolium bromide (VIMB) and 1,2-diaminocyclohexane (DACH) with rich-electron group as guest molecules, respectively, and encapsulated them into a three-dimensional Zn-based MOF Zn-BINOL with large 1D channel (BINOL=(R)-2,2'-diethoxy-1,1'-binaphthyl-4,4',6,6'-tetrabenzoate), as a result, two efficient iodine adsorbents VIMB@Zn-BINOL and DACH@Zn-BINOL were obtained. The equilibrium iodine vapor adsorption amounts of them were 1448 and 1680 mg/g at 75 °C, being about 2.1 and 2.4 times more than that of Zn-BINOL, respectively. This work will provide more synthetic methods on design and preparation of iodine adsorbents with good adsorption capacity.