一锅法水热制备Bi_3O_4Cl-BiOCl复合材料及可见光催化性能研究

One-pot hydrothermal synthesis of Bi_3O_4Cl-BiOCl composites and their photocatalytic performance

以五水合硝酸铋为铋源,通过一锅法水热制备铋基Bi_3O_4Cl-BiOCl复合光催化材料。采用X射线衍射、扫描电子显微镜和紫外可见漫反射对所制备的复合材料进行表征。通过实验发现,该复合材料在可见光下对罗丹明B溶液具有良好的光催化降解能力。制备过程中,溶液酸碱度的变化可调控复合材料组分的质量比,对样品的光催化性能影响较大,其中pH为10.5时制备的样品光催化活性最好,这可能和各组分合适的质量比以及较强的可见光吸收利用能力有关。通过活性物种捕捉实验,确定了光生空穴为光催化反应过程的主要活性物种,由此初步推测出复合材料的光催化机理。

In this study,Bi(NO3)3·5H2O was used as a bismuth source to synthesize various Bi3O4Cl-BiOCl composites through a one-pot hydrothermal route.The as-synthesized samples were fully characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM)and ultraviolet-visible diffuse reflectance spectroscopy(UV-vis DRS).These as-prepared composites showed satisfactory photocatalytic performance toward the degradation of dye Rhodamine B.Among all candidates,sample pH-10.5,synthesized when pH value of the solution was 10.5,exhibited the highest catalytic behavior upon visible-light irradiation,possibly owning to the appropriate proportion of components,smooth interface and strong visible-light response.Active species trapping experiments confirmed the crucial role of holes during catalytic degradation,upon which a possible photocatalytic mechanism was proposed.