Aminotriazole Isomers Functionalized 3d Porous Mxenes for Efficient Elimination of U(Vi) from Wastewater: Performance and Mechanism Investigation

Abstract

Reducing the risk of radioactive contamination was a hot spot in the field of environmental chemistry. Herein, a 3D MXenes with significantly pore structures were fabricated by a template method, which was further adorned with aminotriazole isomers as uranyl-specific nanotrap for separation of U(VI) from wastewater. The spectral analysis demonstrated that two 3D MXenes materials possessed abundant channels, special multilayered structure and high nitrogen content, which facilitated the mass transfer and diffusion of U(VI). The PDA/3-ATA@3D-Ti3C2 and PDA/4-ATA@3D-Ti3C2 offered a uranium capture amounts of 103.1 and 68.3 mg/g from uranium-spiked deionized water with pH=5.0 and 25 °C. The high salinity and humic acid system were not beneficial to separation-immobilization of U(VI), while the inorganic anions exhibited a weak influence on the adsorption properties. Furthermore, the mechanical strength of both MXenes materials was significantly improved, and they were easy to recycle without secondary contamination. Finally, the mechanism analysis showed that the synergistic effect between porous MXenes and aminotriazole isomers enhanced the elimination of U(VI), and elimination process mainly depend on the complexation of U(VI) with the amino and phenolic hydroxyl groups. Thus, this work will improve our understanding of MXenes's potential to remove radionuclides from contaminated water.

Keywords: MXenes, Aminotriazole, U(VI), Adsorption mechanism, Selectivity