BiPO_4/BiVO_4复合材料的制备及可见光催化活性

Preparation of BiPO_4/BiVO_4 Composites with High Visible-light Photocatalytic Activity

采用水热-溶剂热两步法制备了BiPO_4/BiVO_4复合材料.FESEM和TEM分析结果表明,BiVO_4呈高{010},{110}暴露晶面的截角双锥状,BiPO_4纳米颗粒较均匀地附着在BiVO_4表面上,形成了异质结.光电流测试结果表明,异质结能促进光生载流子的有效转移和分离.在可见光作用下,BiPO_4/BiVO_4可有效降解罗丹明B,当BiPO_4与BiVO_4的投料摩尔比为3∶10时,样品的光催化活性最优.

Abstract BiPO4/BiVO4 composites were prepared by combining hydrothermal and solvothermal synthetic methods. Field emission scanning electron microscopy（FESEM） and transmission electron microscopy（TEM） revealed that the as-prepared BiVO4 exhibited a truncated bipyramid morphology with high {0101, { 110} exposed facets, and that the as-obtained BiPO4 nanopartieles were grown on the surface of BiV04, leading to the formation of the BiPO4/BiVO4 heterojunetion. The transient photocurrent-time behaviors indicated that the formed heterojunction made the transfer and separation of the photo-generated carriers more efficient. The as-synthesized BiPOa/BiVO4 composites exhibited high photocatalytic activities in the degradation of rhoda- mine B under visible-light irradiation. It was found that the sample prepared with a BiPOa/BiVO4 molar ratio of 3 ： 10 in the reactants showed the best performance.