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.