Effects of anions on the photoelectrocatalytic degradation of TiO2 coatings using MAO

Titanium oxide coatings(TiO₂/Ti) were formed on the titanium surface by micro-arc oxidation(MAO) in Na₃PO₄ solution.The photocatalytic ability of titanium oxide coatings were evaluated by photocatalytic degradation of Rhodamine B aqueous solution. Using the TiO₂/Ti as anod electrode, the titanium as counter electrode,and with the UV lamp,constant current meter make up the photoelectrocatalytic reactor was built. We have studied the effect of the initial concentration, pH, the concentration of electrolyte, and different anions on the photoelectrocatalytic degradation of Rhodamine B solution. It is found that the impacts of different conditions are different. With the increase of the initial concentration and pH, the removal of Rhodamine B is decreased. The impacts of different anions are also notable, but all of them can improve the efficiency of photoelectrocatalytic. From these studies above, under the conditions are follows, coating TiO₂ film electrode in 5 minutes, the initial concentration is 1.5mg/L, the value of pH is three, the concentration of electrolyte is 0.02mol/L, the effect of photoelectrocatalytic treatment of dye wastewater is best.