The Preparation And Photocatalytic Properties Of Bi₂WO₆ Composites

Photocatalyst material has a potential application in the field of environmental pollutants degradation. Bi2WO6 is the most simple aurivillius type titanium oxide with a calcium seam structure, and has good stability and catalytic activity. It can improve the Bi2WO6 visible light photocatalytic activity via reverse microemulsion methods by introducing PbS or Cu2 S nanoparticles into two-dimensional orientation on the growth of nanometer sheet surface modification. The visible light catalytic activity can be improved, besides, this method has important meaning in resolving problems of low solar energy utilization for semiconductor photocatalysts.The shape of Bi2WO6 powders can be controled via hydrothermal reaction effectively. A series of composite photocatalysts(PbS/Bi2WO6 and Cu2S/Bi2WO6) are synthesized via reverse microemulsion method which can control the size of the chemical compounds and make the PbS compounds uniform distribution on the surface of Bi2WO6 nanoparticles. The composites were characterized using XRD, SEM, TEM, UV-Vis, PL, EDX, XPS, et al. The photocatalytic performance and mechanism of the obtained composites for the degradation of RhB were also investigated and discussed.PbS decrated Bi2WO6 flower like composites exhibit excellent photocatalytic activity. The results show that the photocatalytic performance for the degradation of RhB can be heavily improved by introducing the quantum dots into the surface of Bi2WO6 nanoparticles. Under visible light irradiation, the degradation efficiencies were up to 97% and 96%, respectively(PbS/Bi2WO6 and Cu2S/Bi2WO6 photocatalysts). The recycle experiments indicated that the composites have a good stability after 5 cyclic experiments. Due to the introducing of PbS nanoparticles, the activity can be enhanced. Meanwhile, the matched energy level structure has a capacity of fast transfer photoproduction electrons and can prevent the recombination of photo-carriers effectively. Thus, the photocatalytic performance of the composites can be enhanced largely.