新型复合电极对偶氮染料分子的光催化降解

介绍了具有合成H2O2和光催化性能的双功能新型复合电极,并用X射线衍射、扫描电镜等方法进行了表征.双功能复合电极是将TiO2光催化剂负载在活性碳(AC)和具有合成H2O2性能的新型载体空气电极上形成的.在复合电极作阴极的光反应器中,* OH和TiO2光催化剂的存在实现了光化学氧化与光催化氧化在同一电极/溶液界面上的联合作用.实验结果表明,复合电极对提高偶氮染料分子活性艳红(K-2BP)的氧化降解速度起了重要作用,仅反应3 min,脱色率可达49%;反应80 min,偶氮染料分子COD去除率可达47%.

Photocatalytic Degradation of Azo Dye Using a Novel Composite Elelctrode

A novel composite electrode which had functions of synthesizing H2O2and photocatalysis was reported and characterized by X-rays diffraction and SEM. This double function composite electrode was prepared by the Sol-gel method of loading photocatalyst TiO2/AC on a novel carrier which could synthesize H2O2and separate photogenerated electrons(e-) and holes(h+) efficiently, resulting in improving the reaction rate. In the photo reactor, the composite electrodewas used as a cathode, Ru-Ti-O electrode used as an anode lower pressureHg lamp used as a light source. The combining oxidation of photochemistry and photocatalysis existed at the same interface of electrode-solution. Experiments showed thatTiO2was an anatase phase and homogeneously distributed on the surface of active carbon (AC). So, the effective surface area of the photocatalysts and their absorbability for organic molecules could be increased, providing high concentration environments of organic molecules around TiO2particles and resulting in the enhancement of photocatalytic activity ofTiO2. Although the surface of air electrode was covered with photocatalystTiO2/AC, the current efficiency in H2O2synthesis of the composite electrode was higher as the current density was 15 A/cm2and the efficiency reached about 80%. The experimental results also showed that the composite electrode played an important role in enhancing the oxidation rate of azo dye molecule (activated red K-2BP), in 3 min, the decolorizing rate could reach about 49%, and the removing COD rate could reach about 47% only in 80 min.