Ethylenediamine grafted MIL-101 for iodine vapor capture with high capacity

• Published in: Journal of solid state chemistry Vol. 315; p. 123453
• Main Authors: Tang, Ping, Xie, Xue-Xian, Huang, Zi-Yuan, Cai, Xin-Ting, Zhang, Wei-Guang, Cai, Song-Liang, Fan, Jun, Zheng, Sheng-Run
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.11.2022
• Subjects: Iodine adsorption; Metal-organic framework; MIL-101; MIL-101; Iodine adsorption; Metal-organic framework
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2022.123453

The application of metal-organic frameworks (MOFs) for iodine adsorption is of current interest. As a typical MOF, MIL-101 exhibits good potential in this area. To improve the iodine capture ability of MIL-101, ethylenediamine (ED)-modified MIL-101-ED (x mmol) (x ​= ​1, 5, 10, and 15, representing different amounts of ED) were used for iodine vapor adsorption. Compared with the original MIL-101, all the MIL-101-ED grafted with ED showed higher adsorption capacities than MIL-101, although some of them were amorphous. MIL-101-ED (5 ​mmol) displays the highest capacity of 4.37 ​g ​g−1, which is also in the top set for MOF absorbents. Due to the stronger interaction between MIL-101-ED (5 ​mmol) and iodine molecules, it is transformed into an amorphous structure after the first cycle, leading to a decrease in adsorption capacity. However, the amorphous material is also porous and can be used for the readsorption of iodine vapor, and the adsorption capacity is still higher than that of MIL-101 after the same cycles. In addition, the adsorption capacity of the amorphous structure can be greatly enhanced via modification with ED again. Ethylenediamine grafted MIL-101 were applied to iodine vapor capture in vapor for the first time. The resulting MIL-101-ED display improved iodine adsorption capacities than the original MIL101. [Display omitted] •The ethylenediamine grafted MIL-101were first used to capture iodine in vapor.•The MIL-101-ED (5 ​mmol) displays the iodine adsorption capacity of 1.7 times higher than MIL-101.•The amorphous I2@MIL-101-ED-realease is able to absorb iodine repeatably.•The adsorption capacity of I2@MIL-101-ED-realease can be improved by regrafting of ED.