One-pot synthesis of ferromagnetic Fe2.25W0.75O4 nanoparticles as a magnetically recyclable photocatalyst

To pursue the novel magnetically recyclable photocatalyst, W has been successfully doped in Fe3O4 host matrix for the fabrication of Fe2.25W0.75O4 nanoparticles through a one-pot hydrothermal progress with the addition of sodium dodecyl benzene sulfonate. The size range of the obtained nanoparticles is from 30 to 50 nm determined by SEM. And the particle size is about 41 nm calculated with Debye–Scherrer equation. X-ray diffraction analysis clearly shows that all peaks of Fe2.25W0.75O4 nanoparticles shift slightly toward lower angles relative to those of the standard Fe3O4, which resulted from the substitutions of Fe ions by the bigger W ions in the host lattice. When Fe2.25W0.75O4 nanoparticles were applied to degrade methyl orange under the irradiation of a 10 W UV lamp, it showed a higher decomposition efficiency of 67 % than that of 55 % for normal TiO2 photocatalysts P-25. Moreover, Fe2.25W0.75O4 nanoparticles can be conveniently and quickly recovered with a magnet and no decrease of photocatalytic activity has been observed after several consecutive rounds of photodegradation reaction. The magnetic Fe2.25W0.75O4 nanoparticles with strong photocatalytic ability show promising applications in the degradation of organic pollutants.