具有主导晶面的BiOIO3/BiOCl异质结制备与光催化性能

分别以乙二醇/去离子水为溶剂，通过溶剂热/水热法分别制备了具有不同主导晶面的BiOIO₃/{110}BiOCl和BiOIO₃/{001}BiOCl异质结。采用X射线衍射、扫描电子显微镜、能量色散谱和紫外可见漫反射光谱对制备的BiOIO₃/BiOCl光催化剂进行了表征。在可见光照射下，通过对罗丹明 B和苯酚水溶液的光催化降解，考察了 BiOIO₃/BiOCl异质结的光催化活性。结果显示25% BiOIO₃/{110}BiOCl异质结具有最高的光催化效率。BiOIO₃/{110}BiOCl较好的光催化性能是由于其在可见光区较强的光吸收，以及异质结结构和BiOCl所具有的(110)主导晶面有利于光生载流子的分离。超氧自由基(·O₂^-)和空穴(h⁺)是光催化过程中的主要活性物质。此外，根据实验结果探讨了光催化性能增强的机理。

Preparation and photocatalytic performance of BiOIO3/BiOCl heterojunction with dominated facet

The BiOIO 3/BiOCl heterojunctions with different dominated facet, BiOIO₃/{110}BiOCl and BiOIO₃/{001} BiOCl, were prepared through facile solvothermal/hydrothermal methods with ethylene glycol/deionized water as solvents. As prepared BiOIO₃/BiOCl photocatalysts were characterized by X ray diffraction, scanning electron microscope, energy-dispersive spectroscopy, and UV-Vis diffuse reflectance spectra. The photocatalytic activity of BiOIO 3/BiOCl heterojunctions was evaluated by photo catalytically decomposing rhodamine B and phenol in an aqueous solution under visible light irradiation. The results showed that 25% BiOIO₃/{110}BiOCl heterojunctions exhibited the highest photocatalytic efficiency. The degradation of RhB over 25% BiOIO₃/{110}BiOCl was 98.7% after 15 min of light irradiation. And 100% phenol can be degraded after irradiation for 150 min. The better photocatalytic performance of BiOIO₃/{110}BiOCl may be attributed to the strong absorption of the visible light, the heterojunction structure, and the efficient separation of photo-generated carriers benefiting from the dominated (110) facet of BiOCl. The superoxide radicals (·O₂^-) and holes (h⁺) are the main active species in the photocatalytic process. Moreover, a reasonable mechanism for enhanced photocatalytic performance was also discussed based on the experimental results.