N-取代羧酸聚苯胺接枝石墨烯硫化镉量子点光电材料的研究

发布时间：2018-07-02 09:27

本文选题：石墨烯 + NPAN　；参考：《华东交通大学》2017年硕士论文

【摘要】：随着世界上固有能源的大量消耗及对环境所造成的不可逆影响,人类对于新能源的需求迫在眉睫。而太阳能作为一种清洁、高效、安全的能源备受瞩目,且伴随光电转换技术的不断改进,以半导体光催化剂在太阳光下进行光电转换,实现对清洁新能源的合理利用引起研究者们广泛关注,并且由于半导体类光催化剂良好的催化效果,其在降解有机污染物与产氢两方面具有良好的应用前景。本文旨在研制出一种新型的N-取代羧酸聚苯胺接枝石墨烯硫化镉量子点复合材料,以用作催化效率高、循环稳定性好的光催化剂。在该复合材料中三组分材料间通过共价接枝作用连接,不仅体现了良好的协同效应和界面间作用力,还抑制了各单一组分所存在的缺陷,从而提高了可见光下光电转换的效率。具体的研究内容及相关结果如下:1.以苯胺功能化的还原氧化石墨烯为基体,在原位聚合体系中引入N-苯基甘氨酸与乙酸镉形成含镉前驱体,再利用镉与硫间成核机理制备出复合材料。同时,利用不同途径制备出各种CdS及CdS类复合材料作为对比。通过利用FT-IR、UV-vis、XPS、TEM、TG、Roman、PL等对不同材料的结构、稳定性、形貌等展开探究,结果证明了CdS量子点成功的以共价接枝的方式与石墨烯、聚苯胺相连接,且由于高速导电子性石墨烯的引入及N-取代羧酸聚苯胺对于硫化镉量子点的保护,良好的抑制了CdS的易团聚及光生电子空穴易复合的缺陷。2.采取滴涂法制备出各种CdS复合材料修饰电极,并通过利用CV和EIS对修饰电极的电化学性质展开探究。首先就光照与黑暗条件下,RGO/NPAN-CdS修饰用量、扫描速度、p H等对于该修饰电极活性的影响进行优化。然后经过对比各个修饰电极的CV图与EIS图,得出各电极电子传导能力的差异。最后通过对RGO/NPAN-CdS电极进行循环扫描以检测其稳定性。通过电化学检测证明了:CdS量子点在可见光下能够进行良好光电转换、增强光电流,且由于石墨烯与NPAN的引入,RGO/NPAN-CdS具有更短的界面距离和更快的电子传输速度,在不同CdS复合材料内其具有最高的电活性和最小的电阻,且其稳定性随循环使用依旧保持良好,因此具有应用于实际电化学传感器的潜力。3.在500 W氙灯光源照射下,以纯CdS及不同CdS复合材料为光活性材料进行光催化降解有机污染物Rh B和光催化水产H2反应。首先对于RGO/NPAN-CdS的使用p H与温度进行优化,得出最佳使用条件。然后对比不同CdS类光活性剂降解Rh B与催化产H2能力,得出最佳的催化效果。最后对CdS类材料光催剂的循环使用性展开探索,并通过利用TEM和XRD等对材料光催化前后结构的稳定性进行表征。通过研究能够发现:RGO/NPAN-CdS在光催化反应中皆表现出最高的催化效率与反应速率,其降解Rh B的效率和产H2量分别为单纯CdS的1.94倍于8.6倍,且相较于CdS在光照次数增多后结构被腐蚀、催化效率下降的情况,RGO/NPAN-CdS的结构及光催化的效率都保持良好,这证明了RGO/NPAN-CdS有实际应用于光催化剂的潜力。
[Abstract]:With the enormous consumption of natural energy and the irreversible effect on the environment, the demand for new energy is imminent. As a clean, efficient and safe energy, the solar energy has attracted much attention, and with the continuous improvement of the photoelectric conversion technology, the photoelectric conversion of the semi conductor photocatalyst in the solar light is realized. The rational use of clean new energy has attracted the attention of researchers and has a good application prospect in the two aspects of degradation of organic pollutants and hydrogen production due to the good catalytic effect of semiconductor photocatalyst. This paper aims to develop a new type of N- substituted carboxylic acid polyphenylene graft graphene grafted cadmium sulphide quantum dots composite material It is used as a photocatalyst with high catalytic efficiency and good cycling stability. The covalent graft interaction between three components in the composite not only reflects the good synergistic effect and inter interface force, but also inhibits the defects in the single group, and raises the efficiency of photoelectric conversion under visible light. The content and the related results are as follows: 1. the precursor of N- phenyl glycine and cadmium acetate is introduced in the in-situ polymerization system by the functionalized reduced graphene oxide as the matrix, and the composite material is prepared by the mechanism of cadmium and sulfur. At the same time, various kinds of CdS and CdS composite materials are prepared by different ways as a contrast. FT-IR, UV-vis, XPS, TEM, TG, Roman, PL, etc. have been used to explore the structure, stability and morphology of different materials. The results show that the CdS quantum dots have been successfully linked with graphene, polyaniline, and the introduction of high speed electronic graphene and the protection of the CdS quantum dots by the N- substituted carboxylic polyaniline. It has a good inhibition of the easy reunion of CdS and the defect that the photoelectron hole is easy to compound.2.. Various CdS composite modified electrodes are prepared by the drop coating method, and the electrochemical properties of the modified electrodes are explored by using CV and EIS. First, under the light and dark conditions, the dosage of RGO/NPAN-CdS trimming, the scanning speed, and the P H and so on are used for this modification. The effect of the polar activity was optimized. Then the differences in the electronic conductivity of each electrode were obtained by comparing the CV and EIS diagrams of each modified electrode. Finally, the stability was detected by cyclic scanning of the RGO/NPAN-CdS electrode. It was proved by electrochemical detection that the CdS quantum dots could have good photoelectric conversion and enhanced light under the visible light. Current, and because of the introduction of graphene and NPAN, RGO/NPAN-CdS has shorter interface distance and faster electronic transmission speed. It has the highest electrical activity and minimum resistance in different CdS composites, and its stability remains good with the use of circulation. Therefore, the potential of application to practical electrochemical sensors is at 500 W. Under the irradiation of xenon lamp light source, YISHION CdS and different CdS composites were used for photocatalytic degradation of organic pollutants Rh B and photocatalytic aquatic H2 reaction. First, the optimum use conditions were obtained for RGO/NPAN-CdS using P H and temperature, and then compared the degradation of Rh B and catalytic H2 capacity by different CdS type light active agents. A good catalytic effect. Finally, the recycling of CdS materials was explored, and the stability of the structure was characterized by using TEM and XRD. Through the study, it was found that RGO/NPAN-CdS showed the highest catalytic efficiency and reaction rate in the photocatalytic reaction, the efficiency of degradation of Rh B and the production of H2. The amount of RGO/NPAN-CdS is 1.94 times more than 8.6 times of pure CdS, and the structure and photocatalytic efficiency of the RGO/NPAN-CdS have been kept good compared to the corrosion of the structure and the decrease of the catalytic efficiency, which proves that the RGO/NPAN-CdS has the potential to be applied to the photocatalyst.
【学位授予单位】：华东交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;O643.36

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