Institutional Repository of Key Laboratory of Marine Environmental Corrosion and Bio-fouling, IOCAS
|Thesis Advisor||张杰 研究员|
|Place of Conferral||中国科学院海洋研究所|
|Keyword||偏钒酸银 氧化锌 降解 光催化杀菌 防污|
（1）利用水热法合成具有一维棒状结构的AgVO3纳米材料，然后通过原位生长法在其上负载颗粒状AgBr，成功制备出由AgVO3的（501）晶面和AgBr的（200）晶面紧密结合的AgBr/AgVO3复合材料。光催化降解实验表明，0.5 AgBr/AgVO3复合材料具有优异的光催化活性，在可见光照射下150 min后对RhB的降解率可达到92.3％。由光催化抗菌防污实验得出，在30 min内，使用0.5 AgBr/AgVO3异质结光催化剂，超过99.9970％的E. coli， P.aeruginosa和S. aureus被杀死，说明0.5 AgBr/AgVO3复合材料具有优异的杀菌性能。经过6次杀菌循环实验后，0.5 AgBr/AgVO3复合材料对P.aeruginosa的抗菌率没有明显降低，表明该复合材料具有良好的可重复使用性。根据自由基捕获实验以及上述数据，提出复合材料的光催化机理。
（2）利用水热法和原位生长法制备了具有不同摩尔比的AgBr/Ag2MoO4@AgVO3光催化剂，研究AgBr和Ag2MoO4的不同负载量对所制备的复合材料的光催化活性的影响。结果表明1.0 AgBr/Ag2MoO4@AgVO3光催化剂对RhB溶液具有最好的降解效果，降解率达到了94.9%。在光催化抗菌防污实验中，1.0 AgBr/Ag2MoO4@AgVO3 光催化剂对三种模式菌的杀菌率均超过
（3）利用水热法和原位生长法合成具有Z型结构的AgBr/Ag2MoO4@ZnO复合材料，通过XRD，SEM，XPS和HRTEM等一系列表征手段对所制备的复合材料的形貌，组成和结构等进行表征。选择环丙沙星（CIP）和罗丹明B（RhB）作为目标物进行光降解实验，以揭示制备的复合材料的光催化活性。光催化降解实验表明，0.5 AgBr/Ag2MoO4@ZnO光催化剂在可见光照射下对环丙沙星的降解率为80.5％，表现出较好的光催化降解活性。在光照60 min后，超过99.999％的E. coli，P.aeruginosa和S. aureus被杀灭。此外在5次循环杀菌实验后，该催化剂依旧表现出良好的稳定性，说明0.5 AgBr/Ag2MoO4@ZnO复合光催化剂具有优异的光催化活性。通过自由基捕获实验提出复合材料的光催化反应机理。
Marine biofouling causes great damage to offshore engineering facilities, involving more than 4,000 species of marine life. There are many ways to protect metals from biofouling in marine and the most widely used one is commercial antifouling coating. The method is simple and low cost with excellent efficiency. However, due to the presence of biocides in these coatings, the balance of marine biological system is being damaged. Therefore, it is imperative to develop environmental friendly antifouling coatings or new antifouling technologies.
In this paper, a new type of photocatalytic sterilization and antifouling technology was selected. AgVO3 and ZnO were used as the substrate materials, and they were combined with Ag2MoO4 and AgBr to form composite photocatalysts with different heterojunction structures to enhance light trapping ability, extend the light absorption area, reduce the recombination of electrons and hole pairs, improve their photocatalytic activity and obtain excellent antibacterial antifouling materials. According to the degradation, antibacterial experimental data and free radical trapping experiments, the photocatalytic antibacterial and antifouling activities of the composites were evaluated, and the corresponding photocatalytic reaction mechanism was proposed, which will provide a theoretical basis for the development of stable, efficient and environmental friendly antibacterial antifouling semiconductor materials. The specific research contents were as follows:
(1) The AgVO3 nanomaterial with one-dimensional rod-like structure was synthesized by hydrothermal method, and then AgBr was loaded on the surface by in-situ growth method. The (501) crystal plane of AgVO3 and the (200) crystal plane of AgBr were successfully combined to form the AgBr/AgVO3 composite. The photocatalytic degradation experiments showed that the 0.5 AgBr/AgVO3 composite had excellent photocatalytic activity, and the degradation rate of RhB reached 92.3% after 150 min under visible light irradiation. In the photocatalytic antibacterial antifouling experiment, it was found that more than 99.9970% of E. coli, P. aeruginosa and S. aureus were killed using 0.5 AgBr/AgVO3 heterojunction photocatalyst within 30 min, indicating 0.5 AgBr/AgVO3 composite had excellent antibacterial properties. After 6 cycles of sterilization experiments, The antibacterial rate of 0.5 AgBr/AgVO3 composite to P.aeruginosa did not decrease significantly, indicating that the composite had good reusability. According to the free radical trapping experiment and the above data, the photocatalytic mechanism of the composites was proposed.
(2) AgBr/Ag2MoO4@AgVO3 photocatalysts with different molar ratios were prepared by hydrothermal method and in situ growth method. The effects of different loadings of AgBr and Ag2MoO4 on the photocatalytic activity of the prepared composites were investigated. The results showed that 1.0 AgBr/Ag2MoO4@AgVO3 photocatalyst had the best degradation effect on RhB solution, and the degradation rate reached 94.9%. In the photocatalytic antibacterial and antifouling experiment, the antibacterial rate of 1.0 AgBr/Ag2MoO4@AgVO3 photocatalyst to all three model bacteria exceeded 99.99%. After 5 cycles, the antibacterial rate of the catalyst against P. aeruginosa still reached 98.5942%, indicating that the material had good antibacterial properties and stability.
(3) The AgBr/Ag2MoO4@ZnO composites with Z-type structure were synthesized by hydrothermal method and in-situ growth method. The morphology, composition and structure of the prepared composites were characterized by XRD, SEM, XPS and HRTEM. The photodegradation experiments were carried out by selecting ciprofloxacin (CIP) and rhodamine B (RhB) as targets to reveal the photocatalytic activity of the prepared composites. The photocatalytic degradation experiments showed that the degradation rate of CIP by 0.5 AgBr/Ag2MoO4@ZnO photocatalyst was 80.5% under visible light irradiation, showing good photocatalytic activity. After 60 min of illumination, more than 99.999% of E. coli, P. aeruginosa and S. aureus were killed. In addition, after 5 cycles of sterilization experiments, the catalyst still showed good stability, indicating that the 0.5 AgBr/Ag2MoO4@ZnO composite photocatalyst had excellent photocatalytic activity. The photocatalytic reaction mechanism of the composites was proposed by free radical trapping experiments.
|MOST Discipline Catalogue||理学::海洋科学|
|Table of Contents|
|徐会会. 银盐半导体材料的制备及其光催化防污性能的研究[D]. 中国科学院海洋研究所. 中国科学院大学,2019.|
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