可见光响应TiO2纳米管阵列复合电极光电催化耦合生物降解废水中氯代硝基苯的性能及机制研究

In order to settle low visible light utilization of TiO2 nanotube arrays (TiO2 NAs) and biorefractory degradation of chloronitrobenzenes (CNBs) in wastewater, we shall prepare g-C3N4/TiO2 NAs, CuFeO2/TiO2 NAs and BiOBr/TiO2 NAs composite electrodes with the visible light response, and a system of visible light responsive TiO2 NAs composite electrode photoelectrocatalysis coupling with biological degradation will be established to degrade CNBs in wastewater. The coupling system can make photo-generated electron, photo-generated hole, and biological degradation synergistically degrade CNBs in water. Based on the density functional theory and the photo-generated electron process, the CNBs degradation process is to be explored under the photoelectrocatalysis of visible light responsive TiO2 NAs composite electrode. The effects of light intensity, bias voltage and hydraulic retention time on the CNBs degradation of the coupling system will be investigated from the photoelectrocatalysis process in anodic chamber and biodegradation process in cathode chamber, and the operating parameters and design parameters will be optimized. The dominant microbial community and the abundance of electron transfer protein coding gene are analyzed to explain the microbial community and key gene in the biofilm relating to accelerating the photo-generated electron tranfer of cathode in cathode chamber. The strategy will be explored to accelerate the electron transfer between the electrode and the biofilm. Based on the above-mentioned experimental data, the CNBs degradation mechanism will be revealed in the system of visible light responsive TiO2 NAs composite electrode photoelectrocatalysis coupling with biological degradation.

为了解决TiO2纳米管阵列(TiO2 NAs)可见光利用率低和废水中氯代硝基苯难生化降解的问题，制备可见光响应g-C3N4/TiO2 NAs、CuFeO2/TiO2 NAs和BiOBr/TiO2 NAs复合电极，构建可见光响应TiO2 NAs复合电极耦合生物降解氯代硝基苯的系统，使光生空穴、光生电子和生物降解共同参与降解废水中氯代硝基苯。结合密度泛函理论和光生电子传递过程，探讨可见光响应TiO2 NAs复合电极光电催化氯代硝基苯的降解历程。研究光照强度、偏压和水力停留时间的变化对耦合系统中阳极室光电催化过程和阴极室生物降解过程的影响，优化运行参数。通过分析阴极室内电极生物膜中优势微生物群落及电子传递蛋白编码基因丰度，解析在生物膜中加速阴极光生电子传递的微生物群落与关键基因，探讨电极与生物膜之间加速电子传递的策略，揭示可见光响应TiO2 NAs复合电极光电催化耦合生物降解氯代硝基苯的机制。

针对TiO2纳米管阵列（TNAs）可见光利用率低和氯代硝基苯难降解的问题，制备了BiOBr/TNAs、rGO-BiOBr/TNAs、C3Nm (m = 4, 5)/TNAs、rGO/g-C3N4/TNAs和Au/g-C3N4/TNAs等可见光响应复合电极，优化了制备条件，系统地考察了所制备的光电极的晶型结构、表面形貌、元素组成、官能团组成、光学性能和光电化学性能，评价了不同反应条件下其光电催化降解氯代硝基苯的性能，利用T.E.S.T.软件分析了氯代硝基苯及其降解产物的毒性。通过自由基捕获实验、电子自旋共振光谱、密度泛函理论计算和质谱测定结果确定了光生空穴和羟基自由基在光电催化氯代硝基苯的降解、脱氯和矿化过程中扮演的角色，分析了不同复合电极光电催化降解氯代硝基苯的过程，阐明了基于TNAs复合电极在可见光照射下光电催化降解氯代硝基苯的机理。构建了C3Nm (m = 4, 5)/TNAs光阳极光催化燃料电池耦合类芬顿系统，评价了不同反应条件下该体系对氯代硝基苯降解效率和产电性能，揭示该体系催化降解氯代硝基苯的机理。评价了BiOBr/TNAs复合电极耦合生物降解氯代硝基苯的性能，解析了微生物体系中微生物活性、微生物多样性和丰度的变化。研究成果可为开发高效的氯代硝基苯净化技术提供理论依据和技术支持。