锰离子非均匀掺杂TiO2薄膜电极光电催化测定COD  

COD determination by photoelectrochemical method with Mn nonuniform doping TiO_2 film electrode

作　　者：田玉华[1] 李新军[1] 郑少健[1] 张玉媛[1] 冯满枝[1,2] 

机构地区：[1]中国科学院广州能源研究所 [2]3.中国科学院研究生院,北京100039

出　　处：《生态环境》2008年第2期489-494,共6页Ecology and Environmnet

基　　金：广东省自然科学基金项目(07000743)

摘　　要：COD是水体质量评价的一个重要指标,目前对于COD测定方法主要是高锰酸钾法和重铬酸钾法,这些方法的测定工艺相对繁杂。本文采用溶胶-凝胶法分步控制工艺制备锰离子非均匀掺杂二氧化钛的薄膜电极,并用该薄膜作为光电催化电极测定COD。在三电极体系中,比较该薄膜电极与纯二氧化钛薄膜电极对于氧化丁二酸、乙醇、邻苯二甲酸氢钾、α-D-葡萄糖四种有机物的影响。实验结果表明:三电极体系中电子转移的电量与有机物完全矿化所需的化学需氧量(COD)有着内在的关系。在相同的条件下,锰离子非均匀掺杂二氧化钛的薄膜氧化降解丁二酸、乙醇、邻苯二甲酸氢钾、α-D-葡萄糖的速率大于纯二氧化钛薄膜。进一步结合线性扫描伏安(LSV)、阻抗谱等光电化学表征,从锰离子非均匀掺杂引起二氧化钛薄膜光生空穴-电子分离,初步分析了其光电催化活性提高的机理。Chemical oxygen demand （COD） is one of the most important parameters for water quality assessment. At present the method for COD determination mainly involves potassium permanganate and potassium dichromate. Detenninating technique for these method is most complexity. This article focuses on the electrode of TiO2 film, doped by Mn ion with nonuniform distribution, which was prepared adopting sol-gel method under process control. Chemical Oxygen Demand （COD） was detenninated by photoeleetrocatalysis method with Mn nonuniform doping TiO2 film electrode. In three electrode systems, the Chemical Oxygen Demand （COD） of four kinds of organic matter, succinic acid, ethanol, potassium hydrogen phthalate, α-D-glucose, was photoelectrochemical determined at Mn-TiO2 film electrode and pure TiO2 film electrode. The data of the experimentation indicated that Chemical oxygen demand is directly quantified by measuring the amount of electron transferred at Mn nonuniform doping TiO2 film electrode during an exhaustive photoelectrocatalytic degradation the organic. The degradation ofsuccinic acid, ethanol, potassium hydrogen phthalate, α-D-glucose was more efficient by Mn-TiO2 film electrode compared with pure TiO2 one~ The photoelectrochemistry characterization, EISNyquist plots and LSV, show that Mn non-uniform doping cause the photo-generated carrier separation and photoholes＇ enrichment of TiO2 film electrode, which result in better photo catalytic efficiency.

关 键 词：COD 光电催化 TIO2薄膜 非均匀掺杂 

分 类 号：O644.14[理学—物理化学] O646[理学—化学]