Electro-photocatalytic Fenton Decolorization of Orange G Using Mesoporous TiO₂/stainless Steel Mesh Photo-Electrode Prepared by the Sol-Gel Dip-Coating Method

摘要

A photo-electrochemical process is a powerful and eco-friendly method for treating industrialwastewater. Electro-photocatalytic Fenton (EPF) was employed for orange G decolorization using twokinds of photo-electrodes with TiO2 film-coated stainless steel (SS) mesh. These photo-electrodes areprepared by a dip-coating method from the sol-gel-derived TiO2 sols incorporating with variousamounts of P25+TiO2 powders (SGDC method). The single dip-coated electrode with the TiO2 solcontaining 50 g/L P25 powders possesses similar crystallinity and decolorization performance to thefour repetitive dip-coated electrodes with pure TiO2 sol. The kinetics of orange G decolorization usingP25+TiO2 film electrode in photocatalytic (PC), electro-Fenton (EF) and EPF processes followedpseudo first-order kinetics model, and the EPF has the highest reaction rate. The efficiency of orange Gdecolorization achieves 78% via the EPF reaction for 3 h. The SGDC method using the TiO2 solcontaining P25 powders not only enhances the TiO2 coating on the SS substrate, but also producesmicrocracks in the film, that facilitates the in-situ generation of ferrous ions and further induces theEPF reaction for an effective degradation of organic matter in wastewater.