微弧氧化TiO2膜的电助光催化性能研究

以磷酸钠为电解液,采用微弧氧化技术制备钛基TiO2膜,以该膜为阳极,钛片为阴极与40 W紫外灯和稳压电源组成电助光催化体系,以大红染料模拟废水来评价TiO2膜光电催化能力。研究了酸度和亚铁离子质量浓度等因素对光催化的影响。结果表明:光电催化提高了TiO2膜阳极的降解率;阴极槽内亚铁离子存在会形成电-芬顿体系,有助于提高光电催化降解率。当电解液中支持电解质硫酸钠浓度为0.5 mol/L、pH=3时阳极槽的降解率达到38%,阴极槽亚铁离子质量浓度为3.0mg/L时降解率达到68%。

Study on Electro-assisted Photocatalysis of TiO2 Films Using Micro-arc Oxidation

Titanium oxide(TiO2) coatings were prepared on the titanium surface by micro-arc oxidation(MAO) in Na3PO4 solution.The photocatalytic ability of titanium oxide coatings were evaluated by the photocatalytic degradation of acid brilliant scarlet dye aqueous solution.Using the TiO2 coatings as working electrode and titanium as counter electrode,the electro-assisted photocatalytic reactor was built.The influence of some factors was studied,including initial solution pH value and ferrous concentration.In the reactor,the applied anodic bias prohibit "charge-hole",combination in titanium dioxide anode,and the electro-Fenton's reagent is the key to degrade organic compound of catholyte in which hydrogen peroxide generated through an electrochemical reduction process of dissolved oxygen.When the electrolyte concentration was 0.5 mol/L, initial solution pH was 3,the photocatalytic degradation rate was 38% in anodic compartment.When ferrous concentration in cathodic compartment was 3.0 mg/L,the photocatalytic degradation rate was 68%.