Ultransonic-assisted alcoholysis preparation of BiOCl x Br 1−x modified BiOF microstructure with enhanced photocatalytic performance

A series of BiOF/BiOCl x Br 1−x composites with different BiOF contents have been synthesized by means of ultrasonic-assisted alcoholysis for the first time. The as-prepared samples were characterized by such methods as XRD, SEM, TEM, EDS, Mapping, BET, UV–Vis, XPS and PL spectra. The photocatalytic activity of samples under visible-light irradiation was evaluated by the degradation of Rhodamine. The results revealed that BiOF/BiOCl 0.75 Br 0.25 composite exhibited much higher photocatalytic activity than pure BiOF and BiOCl 0.75 Br 0.25 . And the 30%BiOF/BiOCl 0.75 Br 0.25 composite displayed the highest photocatalytic performance, reaching up 97% after irradiating with visible light for 45 min. The improvement of photocatalytic activity could be ascribed to the increased visible light absorption, its larger specific surface area and the enhanced electron–hole pairs effective separation. Moreover, the·O 2 − and h + were considered as the main active species during photocatalytic process. At last, the possible mechanism of the photocatalytic property was proposed in this paper.