Ag/TiO2光电催化降解染料及出水有机质影响机制

Ag/TiO_(2) photoelectrocatalytic degradation of dye and effluent organic matter influence on its mechanism

本研究以阳极氧化法结合电化学沉积法成功制备的具有高度整齐有序纳米管结构的Ag/TiO2纳米管阵列(Ag/TNTAs)为阳极,碳/聚四氟乙烯为阴极构建光电催化(PEC)体系.并探究其光电催化降解甲基橙(MO)效能,结果表明,Ag/TNTAs光电催化降解能力(68.2%)远高于光催化(18.9%)、电化学氧化(38.2%)和直接光解;另外在水质净化厂出水有机质(EfOM)参与的光电体系中,当EfOM的初始浓度小于或等于1.0mgC/L时,其对光电催化降解MO起到促进作用,其中当其浓度为0.4mgC/L时促进作用最为明显.而高浓度的EfOM则抑制光电催化活性.此研究表明光电催化体系能高效催化染料降解,且EfOM能在一定阈值范围内促进光电催化降解污染物.

A photoelectrocatalysis(PEC)system was constructed to degrade the methyl orange(MO).In this system,Ag/TiO_(2) nanotube arrays(Ag/TNTAs),used as the anode,were prepared with the combination method of anodization and electrochemical deposition,and the carbon/PTFE was used as the cathode.It was found that this Ag/TNTAs PEC system achieved a much higher degradation efficiency of 68.2%than those of photocatalysis(18.9%),electrochemical oxidation(38.2%)and direct photolysis.Besides,the addition of effluent organic matter(EfOM)from water treatment plants could promote the degradation of MO in the Ag/TNTAs PEC system when the initial EfOM concentration was equal or less than 1.0 mgC/L.when the EfOM concentration was 0.4 mgC/L,the enhancing effect achieved the high degree.However,the high concentrations of EfOM inhibited the degradation performance of MO in the PEC system.This study showed that the PEC system could catalyze the degradation of dyes efficiently,and the addition of EfOM within a certain threshold concentration range could further promote the photocatalytic degradation.