Ultra-fast uranium capture via the synergistic interaction of the intrinsic sulfur atoms and the phosphoric acid groups adhered to edge sulfur of MoS2

Abstract

In order to deal with the sudden nuclear leakage event to suppress the spread of radioactive contaminants in a short period of time, it is extremely urgent needed to explore an adsorbent that could be capable of in-situ remedial actions to rapidly capture the leaked radionuclides in split second. An adsorbent was developed that MoS2 via ultrasonic to expose more surface defects afterwards functionalized by phosphoric acid resulting in more active sites being endowed on the edge S atoms of Mo-vacancy defects, while simultaneously increased the hydrophilicity and interlayer spacing. Hence, an overwhelming fast adsorption rates (adsorption equilibrium within 30 s) are presented and place the MoS2-PO4 at the top of performing sorbent materials. Moreover, the maximum capacity calculated from Langmuir model is as high as 354.61 mg·g−1, the selective adsorption capacity (SU) achieving 71.2% in the multi-ion system and with more than 91% capacity retention after 5 cycles of recycling. Finally, XPS and DFT insight into the adsorption mechanism, which can be explained as interaction of UO22+ on the surface of MoS2-PO4 by forming U-O and U-S bonds. The successful fabrication of such a material may provide a promising solution for emergency treatment of radioactive wastewater during nuclear leakage events.