BiVO_4/MOF复合材料的合成及其光催化性能

Modifying BiVO_4 with metal-organic frameworks for enhanced photocatalytic activity under visible light

通过简单溶剂热法制备了一种新型复合光催化剂BiVO_4/M IL-53(Fe);运用XRD、SEM/EDS、FT-IR、N_2吸附-脱附和UV-vis DRS等手段对其进行表征,并对其光催化降解RhB活性进行了研究,提出了相应的光催化降解RhB的可能机理。结果表明,相较于单一BiVO_4材料,复合催化剂的比表面积增大,且其光催化效率相较于纯BiVO_4和MIL-53(Fe)也有了较大的提高;其中,BF-2复合材料的光催化活性最高,分别约为纯MIL-53 (Fe)和BiVO_4的5. 2倍和8. 1倍。同时,BiVO_4/MIL-53(Fe)复合光催化剂经过四次循环实验后,仍能保持较稳定的光催化活性和结构。

A new composite photocatalyst,viz.,BiVO4/MIL-53(Fe),was prepared through a simple hydrothermal approach and characterized by means of X-ray diffraction,scanning electron microscopy,energy dispersive spectrometry,Fourier transform infrared spectroscopy,N2 absorption-desorption and UV-visual diffuse reflectance spectroscopy.The photocatalytic activity of prepared BiVO4/MIL-53(Fe)catalysts was investigated in the degradation of RhB as a simulated pollutant and a possible reaction mechanism for the photocatalytic degradation of RhB was then proposed.The results indicate that after modifying BiVO4 with metal-organic frameworks(MOFs),the surface area of BiVO4/MIL-53(Fe)is improved greatly;moreover,the BiVO4/MIL-53(Fe)composite also exhibits much higher photocatalytic activity than pristine BiVO4 and MIL-53(Fe).In particular,the photocatalytic activity of BF-2 composite is about 5.2 and 8.1 times higher than those of pure MIL-53(Fe)and BiVO4,respectively.In addition,BiVO4/MIL-53(Fe)composite photocatalyst is rather stable and can keep its photocatalytic activity and structure after four recycling tests.