Enhanced visible light catalytic activity of holey Ti3C2 based catalyst for azo dyes

The efficient degradation of organic dye pollutions is of great importance for environmental remediation. In this work, we prepared holey Ti3C2 (H-Ti3C2) and further synthesized H-Ti3C2/Ag/AgX (Cl, Br, I) Schottky catalysts by a simple electrostatic self-assembly method, and found that H-Ti3C2 could significantly improve the catalytic activity and stability of AgX. The H-Ti3C2/Ag/AgX composites showed great visible light absorption, obvious photocurrent intensity, and high charge transfer efficiency, ultimately improving photocatalytic efficacy for the degradation of methyl orange (MO) dye. The composite (5 wt%) H-Ti3C2/Ag/AgBr has the greatest photo-catalytic activity, degrading 99.2% of the MO solution after 40 min of visible light irradiation, which is 1.08 and 2.02 times more than (5 wt%) Ti3C2 /Ag/AgBr and Ag/AgBr, respectively. The photocatalytic performance of H-Ti3C2/Ag/AgBr for MO dyes remains at 51% after five cycles. This result indicates that combining H-Ti3C2 with other photosensitive semiconductors to improve the catalytic activity and stability offers great possibilities. The present work not only provides a simplified method for the preparation of H-Ti3C2/Ag/AgX composites, but also offers a great possibility for H-Ti3C2 MXene as a co-catalyst to increase the photocatalytic degradation efficiency of organic pollutants.

Automated summary

In this study, holey Ti3C2 (H-Ti3C2) was prepared and further synthesized into H-Ti3C2/Ag/AgX (Cl, Br, I) Schottky catalysts by an electrostatic self-assembly method. H-Ti3C2 was found to significantly improve the catalytic activity and stability of AgX. The composite H-Ti3C2/Ag/AgBr showed the highest photo-catalytic activity, degrading 99.2% of the MO solution after 40 min of visible light irradiation.