Construction of BiOBr_xI_1−x/MXene Ti₃C₂T_x composite for improved photocatalytic degradability

Forming BiOBr_xI_1−x solid solution structural photocatalyst has been regarded as an efficient method for photocatalytic property of bismuth oxyhalides (Bi–O–X, X = Br, Cl and I) photocatalysts. In this work, in order to further improve the photocatalytic property of BiOBr_xI_1−x, MXene Ti₃C₂T_x material was used to construct heterostructural photocatalyst with BiOBr_xI_1−x. The MXene Ti₃C₂T_x was achieved by etching the Ti₃AlC₂ with HF and its layered structure was firstly confirmed by X-ray diffraction, scanning electron microscope and high resolution transmission electron microscope. The BiOBr_0.5I_0.5/MXene Ti₃C₂T_x (BOT-5) composite was achieved through a simple synthesis process and its heterostructure was determined by efficient characterizations. Through degradation experiments, the improved photocatalytic degradation property for Rhodamine B (RhB) and phenol of BOT-5 was observed and its excellent chemical stability was also verified meanwhile. The photocatalytic mechanism of BOT-5 was further explored in this work. Through efficient experimental strategies, the enhanced carrier photocatalysis of BOT-5 together with its inhibited extinction photocatalysis was verified. Benefiting from the enhanced carrier photocatalysis of BOT-5, more superoxide and hydroxyl radicals were generated and supported its enhanced photocatalytic degradability.