Nanolayered Ti₃C₂ and SrTiO₃ Composites for Photocatalytic Reduction and Removal of Uranium(VI)

Abstract

Given its promising electron transportation ability, excellent electrical conductivity, and larger work function (6.2 eV) disclosed by density functional theory calculations, MXene material, O-terminated Ti3C2 has the potential to serve as a perfect cocatalyst. Herein, a novel Ti3C2/SrTiO3 heterostructure based on partly superficial oxidation from precursor multilayered Ti3C2 is developed as a photocatalyst for efficiently photocatalytic reduction and removal of U(VI). Specifically, the composite of 2 wt % Ti3C2/SrTiO3 (0.02 Ti3C2/SrTiO3) exhibits an excellent photocatalytic UO22+ removal rate of 77%, which is nearly 38 times higher than that of the pristine SrTiO3. The enhanced photocatalytic performance of 0.02 Ti3C2/SrTiO3 is systematically identified by photoluminescence spectroscopy, UV–vis diffuse reflectance spectroscopy, Raman spectroscopy, and electrochemical characterizations. The multilayered Ti3C2 as a cocatalyst can facilitate the charge transportation and inhibit the recombination of electrons in the conduction band. This work establishes the enticing potential for developing doped perovskite oxide crystals based on the MXene Ti3C2 with sun-light responsivity for improving solar energy utilization.