Degradation of bisphenol A in aqueous solution by H2O2-assisted photoelectrocatalytic oxidation

A series of titanium dioxide (TiO2/Ti) film electrodes were prepared from titanium (Ti) metal mesh by an improved anodic oxidation process and were further modified by photochemically depositing gold (Au) on the TiO2 film surface as Au-TiO2/Ti film electrodes. The morphological characteristics, crystal structure and photoelectroreactivity of both the TiO2/Ti and Au-TiO2/Ti electrodes were studied. The experiments confirmed that the gold modification of TiO2 film could enhance the efficiency of e−/h+ separation on the TiO2 conduction band and resulted in the higher photocatalytic (PC) and photoelectrocatalytic (PEC) activity under UV or visible illumination. To further enhance the TiO2 PEC reaction, a reticulated vitreous carbon (RVC) electrode was applied in the same reaction system as the cathode to electrically generate H2O2 in the aqueous solution. The experiments demonstrated that such a H2O2-assisted TiO2 PEC reaction system could achieve a much better performance of BPA degradation in aqueous solution due to an interactive effect among TiO2, Au, and H2O2. It may have good potential for application in water and wastewater treatment in the future.