Architecture engineering enables high-stability 2D/multi-2D heterostructured MXene/TiO2 for boosting solar-driven CO2 reduction

Photocatalytic CO2 reduction to produce value-added products is considered a promising solution to solve the global energy crisis and the greenhouse effect. In this study, 2D/multi-2D heterostructures were successfully synthesized through electrostatic self-assembly between Ti3C2 and TiO2 nanosheets. The optimal sample (15TC/TiO2) shows yields of 209.98 and 28.09 μmol·g−1·h−1 for CO and CH4, respectively. According to the characterization and simulation study, the enhanced performance is mostly attributable to the 2D/multi-2D heterostructures, which are formed from two phases with huge differences in morphology and size, enabling the development of multiple tiny contact surfaces to increase the effective contact area. In addition, the TiO2 nanosheets utilized in the construction have up to 80 % exposure to the (0 0 1) facets, which offer catalytically active sites. This work provides a feasible method for constructing 2D/multi-2D heterostructure catalyst materials.