Degradation of bisphenol A in aqueous solution by H 2O 2-assisted photoelectrocatalytic oxidation

Abstract

A series of titanium dioxide (TiO 2/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 TiO 2 film surface as Au–TiO 2/Ti film electrodes. The morphological characteristics, crystal structure and photoelectroreactivity of both the TiO 2/Ti and Au–TiO 2/Ti electrodes were studied. The experiments confirmed that the gold modification of TiO 2 film could enhance the efficiency of e −/h + separation on the TiO 2 conduction band and resulted in the higher photocatalytic (PC) and photoelectrocatalytic (PEC) activity under UV or visible illumination. To further enhance the TiO 2 PEC reaction, a reticulated vitreous carbon (RVC) electrode was applied in the same reaction system as the cathode to electrically generate H 2O 2 in the aqueous solution. The experiments demonstrated that such a H 2O 2-assisted TiO 2 PEC reaction system could achieve a much better performance of BPA degradation in aqueous solution due to an interactive effect among TiO 2, Au, and H 2O 2. It may have good potential for application in water and wastewater treatment in the future.