Influence of alternating current electric field on the photocatalytic activity of Mo6+-doped and Ag0-loaded nano-TiO2

• Influence of AC electric field on the photocalytic activity of nano-TiO2 was first reported.
• Not only voltage but also frequency affect the photocalytic activity.
• AC electric field improves the dispersion degree of the nano-particles.

Influence of external applied electric field on the photocatalytic activity of Mo6+-doped and Ag0-loaded nano-TiO2 (Mo6+/Ag0/TiO2) was studied by the degradation of methyl orange (MO). The degradation rate of MO by direct current (DC) electric field could be enhanced to some extent but not proportional to voltage, while the degradation rate of MO by alternating current (AC) electric field was obviously improved along with the increase of frequency. This shows not only the voltage but also the frequency of external electric field affect the photocatalytic activity of the composite catalyst. From the theories of semiconductor and quantum mechanics, the mechanism for AC electric field to promote the degradation of organic pollutant was discussed.