pH值对BiOIO3结构及其光催化性能影响研究

Influence of pH Values on the Structure of BiOIO3 Photocatalysts and Their Performance

采用水热合成法通过调控反应前驱液pH值制备出具有不同形貌结构的碘酸氧铋(BiOIO 3)光催化剂。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和紫外可见吸收光谱(UV vis)等测试方法对合成的样品进行物相、形貌及光学性能表征。以罗丹明B和2,4二氯苯酚的降解效率来评价在不同合成条件下所制备BiOIO3的光催化活性。结果表明,反应前驱液的pH值影响所合成BiOIO3的形貌结构及光催化性能,只有反应液的pH值在酸性条件下,所得产物为纯的BiOIO3。在pH值为2~3的酸性范围内所制备的BiOIO3纳米片具有优异的光催化活性,光辐射15 min时,罗丹明B的降解效率可达95%,光生空穴是主要的氧化活性基团。

A series of BiOIO 3 samples with different structures were successfully synthesized by the hydrothermal method by adjusting the pH value of precursor.The physical and chemical properties of the as-prepared samples were characterized by X-ray diffraction,scanning electron microscopy,and ultravoilet-visible absorption spectrophotometry.The photocatalytic activities were evaluated by the degradation of Rhodamine B and 2,4 DCP in water aqueous.The results showed that the morphology and crystal structure of BiOIO 3 products could be controlled by the pH value of precursor.Only in the strong acid conditions,the products were pure BiOIO 3.The nanosheets sample prepared at 2≤pH≤3 possessed remarkable photocatalytic performance and the degradation ratio of Rhodamine B could reach about 95%after 15 min light irradiation.The photogenerated holes were the main oxidative species responsible for the degradation of RhB.