Boosted CO photoreduction performance on Ru-TiCN MXene-TiO photocatalyst synthesized by non-HF Lewis acidic etching method.

Photocatalytic CO reduction to produce value-added products is considered a promising solution to solve the global energy crisis and the greenhouse effect. In this study, TiCN MXene was synthesized using a Lewis acidic etching method without the usage of toxic hydrofluoric acid (HF). TiCN MXene was then used as a support for the in situ hydrothermal growth of TiO and Ru nanoparticles. In the presence of 0.5 wt% Ru, Ru-TiCN-TiO shows CO and CH production rates of 99.58 and 8.97 μmol/g, respectively, in 5 h under Xenon lamp irradiation, more than 20.5 and 9.3 times that of commercial P25. The enhancement in photocatalytic activity was attributed to the synergy between the in-situ growth of TiO on TiCN MXene and Ru nanoparticles. It was proven experimentally that TiCN MXene can provide abundant pathways for electron transfer. The separation and transfer of the photo-induced charge were further increased with the help of Ru and TiCN MXene, leaving more electrons to participate in the subsequent CO reduction reaction. We believe that this work will encourage more attention to designing environment-friendly MXene-based photocatalysts for CO photoreduction using the non-HF method.