阿特拉津（atrazine, ATZ）即莠去津，因其出色的除草性能被广泛应用和销售。ATZ对玉米等农作物的生产意义重大，但其残效期长，土壤中的ATZ可通过淋溶及地表径流对周围水体和地下水造成污染。ATZ具有急慢性毒性，潜在致癌且有内分泌干扰效应，威胁生态安全和人类健康。臭氧-过氧化氢联用（Perozone）技术是一种基于臭氧氧化的高级氧化技术，去除效率高、环境友好、二次污染少，在水中污染物控制领域有较高的应用潜力。本文以水中阿特拉津为目标污染物，同时开发了用于产臭氧（O₃）的缺陷态Ti/SnO₂-Sb-Ni（NATO）阳极和用于产过氧化氢（H₂O₂）的超疏水炭黑-电喷雾聚四氟乙烯空气扩散阴极（GDE/CB/EP-PTFE），考察了两种电极电化学产O₃和H₂O₂反应活性、选择性和稳定性，进一步阐明了O₃和H₂O₂在电极表面的生成机理；评价了基于两种电极的E-Perozone体系协同降解ATZ的性能，揭示了以羟基自由基（·OH）主导的亲电反应机理和ATZ降解反应路径，同时验证了E-Perozone体系的长期运行稳定性。本文主要研究内容和结论如下：

以溶胶凝胶-热分解法成功制备了NATO电催化阳极材料，阳极氧化生成O₃（electrochemical ozone production, EOP）产率可达2.67 μmol m^-2 s^-1，优于传统的冷电弧放电法。NATO电极表面呈现不均匀的泥质结构，电极表面Ni掺杂会导致电极表面裂纹增多。结构和元素分析结果表明，NATO电极表面的SnO₂呈现四方晶系金红石相结构，Sb和Ni元素的掺入导致SnO₂晶格畸变，结晶度降低，出现缺陷结构。线性扫描伏安（LSV）结果表明，Ni元素的掺入导致NATO电极的析氧电位提高，不同Ni掺杂比例的NATO电极析氧电位值为2.13–2.27V（vs. Ag/AgCl），显著高于未掺杂前的Ti/SnO₂-Sb（ATO）电极（2.12 V vs. Ag/AgCl），且EOP的选择性和电流效率提高，能耗下降。电化学阻抗谱（EIS）显示，NATO电极表面的电流密度均匀，电荷转移阻抗小。此外，考察了多种条件因素对NATO电极EOP效果的影响，结果表明，当原料溶胶中各金属元素摩尔数比满足Ni : Sb : Sn=1 : 8 : 125时，NATO电极EOP效率较优；在单极室电解池中，当交换电流密度为10 mA cm^-2，电解液初始pH=1时，此时法拉第效率为16.0%。进一步地，加速寿命实验也表明，NATO电极即使在强酸电解质中也具有良好的稳定性，其理论寿命约为2008 h。

以炭黑负载-电喷雾法成功制备了GDE/CB/EP-PTFE电催化阴极材料，阴极还原生成H₂O₂（oxygen reduction reaction to hydrogen peroxide, ORR-HP）累积产率可达15.46 g L^-1 h^-1 A^-1，优于已知文献报道。GDE/CB/EP-PTFE阴极具有规整的气体扩散层、催化层和表面疏水层三级结构，表面覆盖均匀，呈强疏水性（接触角139.1 ± 0.5°）。电化学循环伏安扫描（CV）结果显示，GDE/CB/EP-PTFE电极的ORR活性显著优于传统电极。进一步考察了反应器构型、催化层及表面PTFE疏水层构造方式及电流密度对ORR-HP反应的影响。结果表明，使用阳离子交换膜分隔阴极室和阳极室的反应器构型可以避免阳极对生成H₂O₂的消耗，当电流密度为12 mA cm^-2时，电解反应2 h后炭黑负载阴极H₂O₂累积浓度可达到72.0 mmol L^-1；在炭黑负载量为0.5 mg cm^-2，使用Nafion溶液作为催化剂粘合剂，电喷雾负载PTFE层1.0 mg cm^-2、电流密度为12 mA cm^-2的最佳条件下，H₂O₂单位产率可达5.8 mmol L^-1 cm^-2 h^-1。借助原位电芬顿（E-Fenton）反应评价了GDE/CB/EP-PTFE电极原位产H₂O₂在污染物中的实用价值。结果表明，pH=3的原位E-Fenton体系可有效降解ATZ和苯甲酸（benzoic acid，BA），其降解规律均符合一级反应动力学规律，20 min内，ATZ几乎被完全去除，BA去除也可达到91.6%。电子自旋共振（ESR）结果表明，两种污染物的降解均受·OH控制。进一步研究发现，GDE/CB/EP-PTFE电极可利用廉价的自来水和空气以恒定速度产H₂O₂，电流密度为28 mA cm^-2时，电解105 min后H₂O₂的累计浓度高达247.2 mmol L^-1，该结果表明，基于GDE/CB/EP-PTFE阴极的H₂O₂原位生产可在简易的野外条件下展开，无需繁琐的前处理过程。

在E-Perozone降解污染物技术研究方面，首先通过Perozone反应降解ATZ并考察其动力学规律，结果显示，60 min内，在10 mmol L^-1的H₂O₂水溶液中100 μmol L^-1的ATZ浓度未发生明显变化；O₃曝气速率为0.5 L min^-1时，30 min ATZ的降解率为30.8%；将H₂O₂和O₃结合的Perozone体系可有效降解ATZ，在O₃曝气速率为0.5 L min^-1、溶液的初始pH为5的最佳条件下，100 μmol L^-1的ATZ 5 min降解率即高达90.1%。基于自由基检测和中间产物分析，阐明了ATZ在Perozone体系下的降解机理和反应途径。首先阿特拉津在·OH的攻击下，通过脱烷基反应生成脱乙基阿特拉津和脱异丙基阿特拉津，同时也可通过脱氯羟基化反应生成2-羟基阿特拉津；三者均可发生脱烷基反应或脱氯羟基化反应，生成去乙基-2-阿特拉津、去乙基-去异丙基阿特拉津和去异丙基-2羟基阿特拉津，并最终生成去乙基-去异丙基-2羟基阿特拉津，后续的降解过程可能包括开环、生成小分子酸，并进一步矿化为CO₂和H₂O。

进一步地，设计连续实验，考察原位电化学生成H₂O₂及O₃，即采取E-Perozone体系连续处理ATZ模拟废水的运行效率，发现在阴阳极反应联用条件下，阳极效率过低是反应的关键的制约因素；优化实验设计，开发了基于NATO电极的新型组合套筒O₃发生器，该发生器的O₃生成率最高可达120.7 mmol h^-1（5794.6 mg h^-1），与H₂O₂装置联用，可以稳定有效地去除水中ATZ。

Atrazine (ATZ), a widely used chemical herbicide, is one of the highest sales pesticide products. It is of great significance to the production of corn and other crops, but its residual effect period is long. ATZ in the soil can cause pollution to the surrounding water and groundwater through leaching and surface run-off. ATZ has acute and chronic toxicity to people, potential carcinogenesis and endocrine disrupting effect, which severely threaten ecological safety and human health. Perozone is an advanced oxidation technology based on ozone oxidation, which has high removal efficiency, environmental friendliness and less secondary pollution, and has great application potential in the field of pollutants in water. In this research, the ATZ was chosen as the target pollutant and two electrodes were designed for degrading the ATZ. The Ti/SnO₂-Sb-Ni (NATO) anode with defective state was developed for producing ozone (O₃). Besides, super-hydrophobic carbon black-electrospray polytetrafluoroethylene air diffusion cathode (GDE/CB/EP-PTFE) was used to produce hydrogen peroxide (H₂O₂). The reactivity, selectivity and stability of the two electrodes for the electrochemical generation of O₃ and H₂O₂ were investigated. The mechanism of the formation of O₃ and H₂O₂ on the electrode surface was further elucidated. The synergistic degradation of ATZ by E-Perozone system based on two electrodes was evaluated, and the electrophilic reaction mechanism and ATZ degradation pathway dominated by hydroxyl radical (·OH) were revealed. Meanwhile, the long-term stability of E-Perozone system was verified. The main research contents and conclusions of this paper are as follows:

NATO anode was successfully prepared by sol-gel thermal decomposition method. The yield rate of O₃ on anode was 2.67 μmol m^-2 s^-1, which was better than the traditional cold arc discharge method. The surface of the NATO electrode presents an uneven muddy structure, and the Ni doping on the electrode surface leads to the increase of cracks on the electrode surface. The results of structural and elemental analysis show that the SnO₂ on the surface of the NATO electrode exhibits a tetragonal rutile phase structure. The addition of Sb and Ni leads to lattice distortion, reduced crystallinity of the SnO₂.The linear sweep voltammetry (LSV) results showed that the doping of Ni led to an increase in the oxygen evolution potential of the NATO electrode. The oxygen evolution potential of the NATO electrode with different Ni doping ratios ranged from 2.13 to 2.27 V (vs. Ag/AgCl). which is significantly higher than that of the un-doped Ti/SnO₂-Sb (ATO) electrode (2.12 V vs. Ag/AgCl). Improved oxygen evolution potential optimize the selectivity and current efficiency and decrease the energy consumption of the electrochemical O₃ generation process. Electrochemical impedance spectroscopy (EIS) showed that the current density on the surface of the NATO electrode was uniform and the charge transfer impedance was small. In addition, the influence of various factors on the O₃ production efficiency of NATO electrode was investigated. The results show that when the molar ratio of various metal elements in the raw material sol meets the requirement of Ni: Sb: Sn= 1:8:125, the electrochemical O₃ production efficiency of NATO electrode is better. When the exchange current density is 10 mA cm^-2 and the initial pH of the electrolyte is 1, the Faraday efficiency is 16.0% in the unipolar cell. Furthermore, accelerated lifetime experiments also show that the NATO electrode has good stability even in strong acid electrolyte, and its theoretical lifetime is about 2008 h.

GDE/CB/EP-PTFE electrocatalytic cathode material was successfully prepared by carbon black load-electrospray method. The H₂O₂ yield rate reached up to 15.46 g L^-1 h^-1 A^-1, which was better than that reported in previous literature. GDE/CB/EP-PTFE cathode has a three-layer structure which contains a gas diffusion layer, a catalytic layer and a surface hydrophobic layer. It has a uniform, strong hydrophobic (contact Angle 139.1 ± 0.5°) surface. Electrochemical cyclic voltammetry (CV) results showed that the oxygen reduction reaction (ORR) activity of GDE/CB/EP-PTFE electrode was significantly better than that of conventional electrode. The effects of the reactor configuration, the structure of the catalytic layer and the hydrophobic layer on the surface of PTFE and the current density on the reaction of H₂O₂ production were further investigated. The results show that the consumption of H₂O₂ generation by anode can be avoided when the cathode chamber and anode chamber are separated by cation exchange membrane. When the current density is 12 mA cm^-2, the cumulative concentration of H₂O₂ can reach 72.0 mmol L^-1 after 2 hours of electrolytic reaction. Under the optimal conditions of carbon black loading of 0.5 mg cm^-2, Nafion solution as catalyst binder, electrospray loading of PTFE layer of 1.0 mg cm^-2 and current density of 12 mA cm^-2, the unit yield of cathode H₂O₂ could reach 5.8 mmol L^-1 cm^-2 h^-1. The practical value of in-situ production of H₂O₂ by GDE/CB/EP-PTFE electrode was evaluated by in-situ electro Fenton reaction. The results show that ATZ and benzoic acid (BA) can be effectively degraded by in situ electro Fenton system with pH=3, and the degradation law conforms to the first-order reaction kinetics. Within 20 min, ATZ is almost completely removed, and the removal rate of BA can reach 91.6%. The results of Electro Spin Resonance (ESR) show that the degradation of both pollutants is controlled by ·OH. Further study showed that the GDE/CB/EP-PTFE electrode could produce H₂O₂ with cheap tap water and air at a constant rate. When the current density was 28 mA cm^-2, the cumulative concentration of H₂O₂ reached 247.2 mmol L^-1 after 105 min of electrolysis. The in-situ production of H₂O₂ based on GDE/CB/EP-PTFE cathode can be carried out under simple field conditions without tedious pre-treatment process.

In terms of the research on the technology of E-Perozone degradation of pollutants, ATZ was firstly degraded by Perozone reaction and its degradation kinetic law was investigated. The results showed that the concentration of 100 μmol L^-1 ATZ in 10 mmol L^-1 H₂O₂ aqueous solution did not change significantly within 60 min. When the O₃ aeration rate is 0.5 L min^-1, the degradation rate of ATZ 30.8% (30 min). The Perozone system combining H₂O₂ and O₃ can effectively degrade ATZ. When the O₃ aeration rate is 0.5 L min^-1 and the initial pH of the solution is 5, the ATZ degradation rate of 100 μmol L^-1 is as high as 90.1% in 5 min. Based on free radical detection and intermediate product analysis, the degradation mechanism and reaction pathway of ATZ in Perozone system were clarified. Under the attack of ·OH, atrazine first generates deethylatrazine and deisopropylatrazine through dealkylation reaction, and then generates 2-hydroxyl atrazine through dechlorination hydroxylation reaction. The intermediate products further undergo dealkylation reaction and dechlorination to generate deethyl-2-atrazine, deethyl-isopropyl-2-hydroxyl atrazine and deisopropyl-2-hydroxyl atrazine. And eventually, it goes to ethyl-isopropyl-2 hydroxyl atrazine.

Further, continuous experiments were designed to investigate the operating efficiency of in-situ electrochemical generation of H₂O₂ and O₃, namely, the continuous treatment of ATZ simulated wastewater by E-Perozone system. It was found that under the condition of the combination of anode and cathode reaction, the low anode efficiency was the key limiting factor of reaction. A novel combination jacket O₃ generator based on the NATO electrode was developed to optimize the experimental design. The O₃ generation rate of the generator could reach up to 120.7 mmol h^-1 (5794.6 mg h^-1). AWhen combined with the H₂O₂ device, the generator could remove ATZ in water stably and effectively.