Preparation And Properties Of Bismuth-based Visible-light-driven Photocatalyst

The Bismuth resources in our country are rich, however, the utilization is limited,therefore, the study of bismuth is of great significance. The Bi2S3-BiOCl composites was synthesized via anion exchange route for the first time,Bi-Bi2O3-Bi2MoO6 composites,CoMoO4 of different reaction times and Bi2MoO6-CoMoO4 composites,Ag deposited on Bi2MoO6 are,for the first time,synthesized through an simple hydrothermal method. The samples are characterized by scanning electron microscope(SEM), X-ray diffraction (XRD), UV-vis diffused reflectance spectra(UV-DRS), transmission electron microscope(TEM), Brunauer-Emmett-Teller(BET),photocurrent response, X-ray photoelectron spectroscopy(XPS). The photodegradation performances of the materials are investigated by using wastewater containing reactive brilliant red (X-3B), methyl orange (MO) and rhodamine B (RhB)as the simulated industry wastewater. Besides, the mechanism on the enhancement of photocatalytic activity was proposed. The results are as follows:1. The sample Bi2S3-BiOCl (8:4) exhibited the highest photodegradation efficiency while degradating reactive brilliant red dye solution under visible light irradiation, which was six times faster than that of pure BiOCl,the enhanced activity was astributed to the formation of Bi2S3 on BiOCl nanoplates.2. The Bi-Bi2MoO6-Bi2O3 photocatalysts exhibit higher efficiencies than bare Bi2MoO6, the longer the reflow time is, the higher the photodegradation efficiency is,the reason of which is that, the crystallinity of the samples is better when the reflow time extends.3. The Bi2MoO6-CoMoO4 photocatalysts exhibit higher efficiencies than bare Bi2MoO6 and CoMoO4 mainly attributed to the formation of stable heterojunctions between Bi2MoO6 and CoMoO4,which has greatly improved the separation of photogenerated carriers.4. When the pH value was 11, the amount of Ag was 15mmol,Ag-Bi2MoO6 photocatalyst shows the highest degradation performance while degradating 5ppm Rhodamine B dye solution under visible light irradiation, which ascribe to the Ag on the surface of Bi2MoO6 transferred photogenerated electrons in time as electron acceptor thus improve the separation efficiency of electrons and holes.