Layered BiOBr/Ti3C2 MXene composite with improved visible-light photocatalytic activity

Layered BiOBr/Ti3C2 (BTC) composites were synthesized by first preparing Ti3C2 nanosheets through the liquid etching of Ti3AlC2 powder and then hybridizing with BiOBr via a facile reflux process. The morphology, crystal structure, light-harvesting capacity, chemical nature of atoms and visible-light photocatalytic degradation activity were systematically studied and discussed. It was found that the introduction of Ti3C2 nanosheets improved UV-Vis light absorption region of BiOBr. A contact interface was formed between BiOBr nanoplate and Ti3C2 nanosheet due to the similar layered structures, which could accelerate the efficient separation and transfer of photoinduced electrons and holes. Thus, the obtained BTC composites showed the higher visible-light photocatalytic activity for the degradation of RhB than pure BiOBr. The generated active species were determined by the active species capture experiment and ESR spectra, showing that (<bold>)</bold>O-2(-) and (<bold>)</bold>OH played a crucial role in the photocatalytic degradation of RhB. The corresponding photocatalytic mechanism was proposed. This work may provide a new insight into the construction of earth-abundant MXene-based photocatalysts with high performance and low cost.