Rapid synthesis of polyimidazole functionalized MXene via microwave-irradiation assisted multi-component reaction and its iodine adsorption performance.

The adsorption applications of MXene-based adsorbents have intensively investigated recently. However, the performance of MXene-based adsorbents has been largely limited owing to their lack of functional groups and adsorptive sites. Therefore, surface functionalization of MXene is an important route to achieve better performance for environmental adsorption. Herein, polyionic liquid functionalized MXene (named as MXene-PIL) was prepared through a multi-component reaction and adsorptive removal of iodine by MXene-PIL was also evaluated. The successful generation of PIL on MXene was confirmed by a series of characterization measurements. Furthermore, the effects of contact time, iodine concentration, environmental temperature and other factors on the adsorption performance of MXene-PIL were investigated. Adsorption kinetic analysis including pseudo-first-order dynamic model, pseudo-second-order dynamic model and Weber-Morris model, adsorption thermodynamic analysis such as Langmuir and Freundlich models and Van't Hoff equation were used for further analysis the adsorption behavior of iodine by MXene-PIL. We demonstrated that the adsorption capacity could be as high as about 170 mg/g, which is obviously larger than the unmodified MXene and most of other reported adsorbents. Taken together, a simple strategy has been developed for in-situ generation of PIL on MXene and the resultant composites show potential application for adsorptive removal of iodine.