Photocatalytic production of hydrogen peroxides and organic peroxides in aqueous suspensions of titanium dioxide, zinc oxide, and desert sand

The formation of H_2O_2 and organic peroxides in illuminated aqueous suspensions of ZnO, TiO_2, and desert sand in the presence of O_2 and organic electron donors has been studied. The photocatalytic rate of formation of H_2O_2 on ZnO was shown to depend on the O_2 partial pressure, on the concentration of organic electron donors, and on the concentration of H_2O_2.