Conference Paper

Photocatalytic degradation of methylene blue by magnetically separable BiVO4 supported on Fe3O4 nanoparticles

Dept. of Environ. & Municipal Eng., North China Univ. of Water Conservancy & Electr. Power, Zhengzhou, China
DOI: 10.1109/ESIAT.2010.5568721 Conference: Environmental Science and Information Application Technology (ESIAT), 2010 International Conference on, Volume: 1
Source: IEEE Xplore


Non-titania photocatalyst BiVO4 was supported on SiO2-coated Fe3O4 particles in order to solve the problems of photocatalyst recovery and reuse. The prepared photocatalyst BiVO4/SiO2/Fe3O4 (BiVO4/SFN) was proved to be nano-sized (less than 10 nm) by TEM characterization. The superparamagnetism of BiVO4/SFN was confirmed by a vibrating sample magnetometer (VSM). The photocatalyst can be easily separated experimentally by an external magnetic field in lab. XRD analysis proved the dominant existence of BiVO4 crystals. The magnetic photocatalyst BiVO4/SFN showed high photoactivity for methylene blue (MB) decolorization under visible light above 400 nm (72.1%) and a lower activity (21.8%) was observed under line spectra at 420 nm. MB was almost not degraded by P25 titania at 420 nm. The reusability experiment under visible light irradiation also demonstrated the potential application of magnetic photocatalyst in water and wastewater treatment.

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