Chemiluminescence Study of the Generation of Active Oxygen Species on the Surface of TiO2:MoO3 Charge-Accumulating Photocatalysts

A chemiluminescence technique was used to establish that, in contrast to TiO2 photocatalysts, TiO2:MoO3 composite photocatalysts suppress the photogeneration of superoxide ions, while the capture of photoelectrons in the MoO3 phase to give reduced Mo(V) states creates conditions for the long-term generation of hydrogen peroxide capable of acting as a biocide. The TiO2:MoO3 accumulating photocatalysts were shown to be fully reusable and the cycle of photocharging followed hydrogen peroxide generation can be repeated multiple times.