随着工农业的快速发展，大量常规处理难以高效去除的污染物排放到自然水体中，给生态平衡和人类健康带来了严重威胁，因此开发高效低耗的深度处理技术是保障水质安全的关键。抗生素和重金属在环境中均具有持久性和毒性，两者共存时产生的复合污染毒性更大，常规处理技术去除效能有限。因此，开发一种可高效低耗实现抗生素降解同步重金属离子去除的工艺是当前的研究热点之一。光电催化作为一种新兴的“绿色”技术，因其可以在较低能耗下实现氧化和还原反应的同步进行而受到了研究者的广泛关注。电极作为光电催化工艺的关键核心，其性能将直接决定光电催化技术对污染物的去除能力。因此，开发高效的电极材料对于光电催化技术的发展具有重要意义。本论文针对现有电极材料所存在的不足，开发了具有强氧化性能的阳极材料BiOBr/RGO/TCPP和具有强还原性能的阴极材料异相MoS₂。以四环素（TC）和Cr(Ⅵ)作为目标污染物，分析了两种电极材料的光（电）催化性能及反应机理。最后，将BiOBr/RGO/TCPP-异相MoS₂电极体系应用于光电催化系统中，考察了有机污染物降解同步重金属离子还原的效能，并分析了电极的协同机制。

主要工作内容如下：

（1）基于异质结工程策略制备了光阳极催化剂BiOBr/RGO/TCPP Z型异质结，研究了其对四环素的光降解效能和机理。当四环素的初始浓度为40 mg/L时，BiOBr/RGO/TCPP复合催化剂可在60 min内达到89.66%的去除效率，比原始的BiOBr提高了18.5%。同时，急性抗菌效力实验和ECOSAR模型则表明反应液的毒性大幅度降低，其中对大肠杆菌的生长抑制率从原本的17.46%降至0.97%。BiOBr/RGO/TCPP复合催化剂优异的光催化活性是由于RGO和TCPP的引入增强了BiOBr的光吸收能力，同时Z型异质结的构建加快了光生载流子的分离效率。此外，TCPP的低导带位置有利于·O₂^-的生成，进一步加强了体系的氧化性能。

（2）基于晶相结构调控策略制备了异相MoS₂电极，研究了其对Cr(Ⅵ)的电还原效能和机理。当Cr(Ⅵ)的初始浓度为10 mg/L时，在反应液pH为4.0和外加偏压为-1.0 V的条件下，异相MoS₂电极可在60 min内达到92.39%的去除效率，远高于石墨毡和2H相MoS₂电极的34.62%和29.35%。异相MoS₂电极优异的电催化还原性能归因于电极组成中含有较高比例的1T相结构，使得电极具有更多的催化活性位点和更快的电子迁移能力。条件实验表明电催化过程中Cr(VI)的去除存在两种路径，主要路径是通过电子的作用将Cr(VI)直接还原，次要路径是通过产生的少量H₂O₂将Cr(VI)间接还原。

（3）分析了BiOBr/RGO/TCPP-异相MoS₂电极体系光电催化降解有机污染物同步还原重金属离子的性能及机理。在光电催化条件下，60 min内可实现74.81%的四环素（40 mg/L）去除效率和85.87%的Cr(VI)（15 mg/L）去除效率，高于BiOBr/RGO/TCPP-Pt体系光电催化降解四环素的效率和Pt-异相MoS₂体系电催化去除Cr(VI)的效率，表明BiOBr/RGO/TCPP-异相MoS₂体系具有更好的协同作用。LSV的测试结果则进一步证明BiOBr/RGO/TCPP-异相MoS₂体系更好的协同作用归因于光电压补偿了阴极还原Cr(VI)所需的电动势。

With the rapid development of industry and agriculture, a large number of pollutants that are difficult to be efficiently removed by conventional treatment are discharged into natural water bodies, posing a serious threat to ecological balance and human health. Therefore, the development of wastewater advanced treatment technologies with high efficiency and low consumption is the key to ensuring water quality. Both antibiotics and heavy metals are persistent and toxic in the environment. When the two coexist, the compound pollution produced is more toxic, and the removal efficiency of conventional treatment technologies is limited. Therefore, it is one of the current research hotspots to develop a technology that can realize the degradation of antibiotics and simultaneous removal of heavy metal ions with high efficiency and low consumption. As an emerging "green" technology, photoelectrocatalysis has attracted extensive attention of researchers because it can achieve simultaneous oxidation and reduction reactions with low energy consumption. As the key core of the photoelectrocatalytic process, the performance of the electrode will directly determine the removal efficiency of pollutants. Therefore, the development of efficient electrode materials is of great significance for the development of photoelectrocatalytic technology. Aiming at the shortcomings of existing electrode materials, this study developed BiOBr/RGO/TCPP, an anode material with strong oxidative properties, and heterophase MoS₂, a cathode material with strong reduction properties. Taking tetracycline (TC) and Cr(Ⅵ) as target pollutants, the photo(electro)catalytic performance and reaction mechanism of the two electrode materials were analyzed. Finally, the BiOBr/RGO/TCPP- heterophase MoS₂ electrode system was applied in a photoelectrocatalytic reactor, the removal efficiency of pollutants was investigated, and the synergistic mechanism of the electrodes was analyzed.

The main research contents as follows:

(1) The photoanode catalyst BiOBr/RGO/TCPP Z-Scheme heterojunction was prepared based on the heterojunction engineering strategy, and its photodegradation efficiency and mechanism of tetracycline were investigated. When the initial concentration of tetracycline was 40 mg/L, the BiOBr/RGO/TCPP ternary catalyst could achieve a removal efficiency of 89.66% within 60 min, which was 18.5% higher than that of the primitive BiOBr. At the same time, the acute antibacterial efficacy experiment and the ECOSAR model showed that the toxicity of the reaction solution was greatly reduced, and the growth inhibition rate of E. coli decreased from 17.46% to 0.97%. The excellent photocatalytic activity of the BiOBr/RGO/TCPP ternary catalyst is due to the introduction of RGO and TCPP to enhance the light absorption capacity of BiOBr, and the construction of the Z-Scheme heterojunction accelerates the separation efficiency of photogenerated carriers. In addition, the low conduction band position of TCPP contributes to the generation of ·O₂^-, which further enhances the oxidation performance of the system.

(2) Heterophase MoS₂ electrode was prepared based on the control strategy of crystal phase structure, and its electroreduction efficiency and mechanism of Cr(VI) were investigated. When the initial concentration of Cr(Ⅵ) was 10 mg/L, the heterophase MoS₂ electrode could achieve a removal efficiency of 92.39% within 60 min (-1.0 V, pH 4.0), which is much higher than that of graphite felt and 2H phase MoS₂ electrode. The excellent electrocatalytic reduction performance of the heterophase MoS₂ electrode is attributed to the higher proportion of 1T phase structure in the composition of the electrode, which enables the electrode to have more catalytically active sites and faster electron mobility. Conditional experiments show that there are two pathways for the removal of Cr(VI) in the electrocatalytic process. The primary pathway is the direct reduction of Cr(VI) by the action of electrons, and the secondary pathway is the indirect reduction of Cr(VI) by a small amount of generated H₂O₂.

(3) The performance and mechanism of BiOBr/RGO/TCPP-heterophase MoS₂ electrode system for photoelectrocatalytic degradation of organic pollutants and simultaneous reduction of heavy metal ions were analyzed. Under the experimental conditions of photoelectrocatalysis, 74.81% tetracycline (40 mg/L) removal efficiency and 85.87% Cr(VI) (15 mg/L) removal efficiency can be achieved within 60 min, which are higher than those of BiOBr/RGO/TCPP-Pt system for photoelectrocatalytic degradation of tetracycline and Pt-heterophase MoS₂ system for electrocatalytic removal of Cr(VI). Experimental results show that BiOBr/RGO/TCPP-heterophase MoS₂ system has better synergy. The LSV test results further prove that the better synergistic effect of BiOBr/RGO/TCPP-heterophase MoS₂ system is attributed to the photovoltage compensating the electromotive force required to reduce Cr(VI) at the cathode.