AgII doped MIL-101 and its adsorption of iodine with high speed in solution.

In order to improve the adsorption speed of iodine from water, MIL-101 with extra-large specific surface area (3054 m 2 /g) was chosen as a base material, and then, Ag was doped into MIL-101 to enhance its adsorption capacity through an incipient-wetness impregnation method. With the characterization of SEM-EDS, TEM, XRD, XPS, TGA, IR, and BET techniques, the resulting Ag was identified to be stay in the framework of MIL-101 stably in the form of Ag II (generally, Ag II cation is not stable). However, after the adsorption of I − anions, Ag II stay in the cages of MIL-101 in the form of AgI/AgI 3 . It is important to note that, all adsorbents show high adsorption speed of iodine in solution. The equilibrium adsorption time of the adsorbents were acquired by only a few minutes, which can be attributed to its large BET surface area. An interesting note is that, when the doping amount of Ag is less than 9%, the iodine anions adsorption capacity of Ag@MIL-101 is greater than its theoretical adsorption capacity. It shows that both physical adsorption and chemical adsorption are existed in the adsorption process. This study hopefully leads to a new and highly efficient Ag-based adsorbent for iodide adsorb from solutions. [ABSTRACT FROM AUTHOR]