Design of 2D/2D heterojunction of Ti3C2/BiOClxBr1−x for enhancing photocatalytic performance

Newly emerged 2D metallic Ti 3 C 2 is highly spotlighted for its unique properties and ubiquitous compounding compatibility. Herein we pioneeringly demonstrate a heterojunction photocatalyst of Ti 3 C 2 /BiOCl x Br 1−x . X-ray diffraction, scanning electron microscope , transmission electron scope, and X-ray photoelectron spectroscopy analysis indicates that BiOCl x Br 1−x is successfully in-situ grown upon Ti 3 C 2 nanosheets . Visible light photocatalytic performance of 7 %-Ti 3 C 2 /BiOCl 0.25 Br 0.75 is overwhelmingly superior to BiOCl x Br 1−x with an increment of 11.9 times in the reaction rate constant of RhB photodegradation , owing to the distinctive Schottky heterojunction between Ti 3 C 2 and BiOCl x Br 1−x . UV–vis absorbance, photoluminescence , Fourier transform infrared spectra , Raman, electrochemical impedance spectra, and transient photocurrent response account for the improved utilization of visible light, effective separation of photogenerated carriers, and more photogenerated electron acceptors , which elucidate the superior photocatalytic performance and good stability of Ti 3 C 2 /BiOCl x Br 1−x . Trapping experiments and electron paramagnetic resonance tests verify that the dominant active species of·O 2- and h + are responsible for the rapid degradation of RhB. The reasonable photocatalytic mechanism of Ti 3 C 2 /BiOCl x Br 1−x is clarified based on the energy band structure and synergistic effect of the heterojunction. This work provides some novel insights into designing 2D layered heterojunction photocatalysts, boosting photocatalytic performance, and advancing Ti 3 C 2 application.