Novel Bi19S27Br3 superstructures: facile microwave-assisted aqueous synthesis and their visible light photocatalytic performance

Novel hierarchical Bi19S27Br3 superstructures have been synthesized on a large scale by a facile and green microwave-assisted aqueous chemical process for the first time. The products have been characterized by XRD, FESEM, TEM, HRTEM, SAED and UV-vis diffuse reflectance spectrum (DRS). The results reveal that the self-supported fabric-like Bi19S27Br3 superstructures possess a hexagonal phase with diameters of 4-5 μm, constructed by cross-bedded nanofibers with average diameters of about 80 nm. Further, the nanofibers are aggregated by ultrafine nanosilks containing stacking faults. The UV-vis DRS shows that the Bi19S27Br3 superstructures have significant absorption in the visible region, from which the band gap energy is calculated to be 1.42 eV. According to the photodegradation of Rhodamine B under visible lighting, the Bi19S27Br3 superstructures display high efficient catalytic performance. This work may reignite the intensive study of the higher-order sulfohalogenides.