Mxene-TiO2 composite with exposed {101} facets for the improved photocatalytic hydrogen evolution activity

Fabricating Ti3C2Tx Mxene based composite with good control of size, morphology and facet for the high-efficiency photocatalytic application is of great potential and highly challenging. In this work, Ti3C2-TiO2 composite are prepared by a simple two-phase assembling method from the Ti3C2 Mxene dispersion modified with tetraethyl hydroxyl ammonium (TEHA) and rhombic-shaped TiO2 nanoparticles with exposed {101} facets. The Ti3C2 Mxene acts as a good support to anchor TiO2 nanoparticles of 15 nm with good facet control. A significantly enhanced photocatalytic hydrogen evolution activity is acquired by the Ti3C2-TiO2 composites. The highest H2 production rate of 390.92 μmol h−1 is gained by the Ti3C2-TiO2 composites with the Ti3C2 weight percentage of 6.7%, which is 2.1 times that of pristine TiO2. The excellent photocatalytic activity can be attributed to the extended light absorption, the boost charge separation efficiency and exposed {101} facets in the TiO2 nanoparticles. This work provides a new strategy to prepare high quality MXene Ti3C2-TiO2 hybrids with good photocatalytic properties, which could be widely applied to produce other MXene-based composites with excellent properties.