Photocatalytic Ozonation of Oxalic Acid Over Cu(II)-Grafted TiO2 Under Visible Light Irradiation

An efficient photocatalytic ozonation system that is sensitive to visible light was designed and fabricated over Cu(II)-grafted TiO2. The results show that oxalic acid was degraded efficiently in this system under visible light. This high efficiency was attributed to the synergetic effect of photocatalysis and ozonation, which facilitated the generation of holes on TiO2 and hydroxyl radicals. Moreover, Cu(II)-grafted TiO2 proved to be very stable in the reaction without any deactivation and the Cu ions would not leach from TiO2 to aqueous solution. Therefore, this photocatalytic ozonation system is promising to purify wastewater with refractory pollutants under visible light.