0D/2D Heterojunctions of Ti3C2 MXene QDs/SiC as an Efficient and Robust Photocatalyst for Boosting the Visible Photocatalytic NO Pollutant Removal Ability

In this work, a novel heterojunction catalyst was constructed by introducing Ti₃C₂ MXene quantum dots (QDs) into SiC. The Ti₃C₂ MXene QDs/SiC composite showed 74.6% efficiency in NO pollutant removal under visible light irradiation, which is 3.1 and 3.7 times higher than those of the bare Ti₃C₂ MXene quantum dots and SiC, respectively. The Ti₃C₂ MXene quantum dots existing in SiC can function as a channel for electron and hole transfer. The enhanced visible light absorption, increased superoxide radical, and strong oxidization ability endow the Ti₃C₂ MXene QDs/SiC composite with a superior photocatalytic performance for NOx removal. The increased superoxide radical formation and enhanced oxidization ability of Ti₃C₂ MXene QDs/SiC were demonstrated by theoretical calculations. The robust stability in both photocatalytic performance and crystal structures was revealed in the Ti₃C₂ MXene QDs/SiC composite using the cycling test, transient photocurrent response, XRD, and TG.