Magnetic field effect on the photocatalytic degradation of methyl orange by commercial TiO 2 powder.

In this work, by taking commercial P25 hydrophilic titanium dioxide (TiO 2 ) as a photocatalyst, the magnetic field effect (MFE) on the photodegradation rate of methyl orange is studied. It is found that a relatively lower magnetic field B = 0.28 T can efficiently enhance the photodegradation efficiency of commercial TiO 2 by 24%. However, the photodegradation efficiency of commercial TiO 2 will be suppressed slightly by 7% under a magnetic field of 0.5 T. Moreover, such MFE on the photocatalyst is dependent on the settling state of the reaction solution. Additional experiments on the degradation of other pollutants (methylene blue) and with other photocatalysts (g-C 3 N 4 ) indicate that the MFE is a ubiquitous phenomenon in the photocatalytic degradation process. These observations suggest that the magnetic field can be taken as an efficient strategy to regulate the catalytic process of commercial catalysts and improve the catalytic efficiency.