石墨烯基复合材料的制备及其光催化与吸附性能研究

发布时间：2018-01-17 01:28

本文关键词：石墨烯基复合材料的制备及其光催化与吸附性能研究　出处：《安徽大学》2017年硕士论文　论文类型：学位论文

【摘要】：近年来,环境污染问题已经成为了人类必须面对的主要问题。如何高效解决水污染问题已经引起了人们广泛的关注。迄今为止,人类已经采用了很多先进的技术用来处理污水中的有机染料和重金属离子,比如共沉淀,电渗析,絮凝,离子交换,反渗透和吸附等。在这些方法当中,光催化和吸附是最有效的方法,因为这两种方法易于操作,成本低,效益高,并且能够广泛使用。石墨烯基材料作为一种新型的复合材料,因具有表面积大,电子传输性能优异、绿色廉价等优点,受到了广大科研工作者们的青睐,被广泛应用于光催化降解和吸附等领域。基于此,本文首先制备得到巯基乙胺修饰的氧化石墨烯(GO-SH),然后在GO-SH表面负载上Fe3O4纳米粒子得到磁性的GO-SH-/Fe3O4材料,并研究了 GO-SH/Fe3O4吸附水溶液中Ag+的性能;采用一步水热法制备掺杂不同比例二硫化钼(MoS2)的MoS2rRGO复合水凝胶,重点研究了 MoS2-RGO复合水凝胶对有机染料亚甲基蓝(MB)的光催化降解性能,并且也进行了部分电化学性能的研究;采用一步水热法将GO溶液,MoS2溶液和壳聚糖(CS)溶液一步制得GO-MoS2-CS复合水凝胶,研究了该复合水凝胶对MB的吸附性能。本课题的主要研究内容及结论如下:1.第一步,采用改进的Hummers法合成了 GO,然后用巯基乙胺和石墨烯上的羧基进行反应,得到GO-SH。接着,用共沉淀法在GO-SH表面负载上Fe304纳米粒子。通过FT-IR、TGA、TEM和XPS等测试方法对GO-SH/Fe3O4复合材料进行了表征。最后,研究了 GO-SH/Fe304吸附Ag+的性能。结果表明GO-SH对Ag+的平衡吸附量为68.2 mg·g-1,而未改性的GO对Ag+的平衡吸附量为40.3 mg·g-1。实验结果表明,GO-SH对Ag+的吸附效果比GO对Ag+的吸附效果好。而且,GO-SH/Fe3O4复合材料具有良好的超顺磁性,这表明GO-SH/Fe3O4吸附剂可以很方便的进行回收处理。2.采用氧化还原法制备得到GO,用锂离子插层法制备得到片层的MoS2。随后采用一步水热法制备掺杂不同比例的MoS2-RGO复合水凝胶。重点研究了MoS2-RGO复合水凝胶对MB的光催化降解性能,并且也进行了部分电化学性能的研究。结果表明MoS2和GO在水凝胶中分散的很好。MoS2-GO复合水凝胶对MB溶液具有很好的光催化降解性能(60 min降解率达到99%)。这是因为MoS2的引入提高了光生电子的数量;石墨烯作为一个优良的导体,可以及时地转移走光催化过程中的光生电子,使得光生电子-空穴对重新复合的几率大大降低了。3.首先,制备出片层的GO和MoS2。然后采用一步水热法将GO溶液,MoS2溶液和CS溶液一步制得GO-MoS2-CS复合水凝胶,并用FT-IR、SEM、TGA和XRD等对其进行了表征。研究了该复合水凝胶对MB溶液的吸附性能,结果表明GO-MoS2和GO-MoS2-CS复合水凝胶对MB的平衡吸附量分别为136.01 mg/g和206.16 mg/g。这说明GO-MoS2-CS复合水凝胶对MB具有更好的吸附性能。经过两次循环之后,GO-MoS2-CS复合水凝胶对MB的吸附量仍能达到初始平衡吸附量的73%。由于MoS2具有的光催化性能,而GO又可以及时的转移光生电子,提高MoS2的催化性能,这就使得该复合水凝胶在光照下就可以降解其吸附的MB,代替了传统吸附剂需要用酸性或碱性溶液进行解吸附。该操作简单绿色,便于吸附剂循环利用。
[Abstract]:In recent years, the problem of environmental pollution has become the main problem that human beings have to face. How to efficiently solve the water pollution problem has attracted extensive attention. So far, humans have adopted a lot of advanced technology for treatment of organic dyes and heavy metal ions in wastewater, such as precipitation, electrodialysis, flocculation, ion exchange. Reverse osmosis and adsorption. Among these techniques, photocatalytic and adsorption is the most effective method, because these two kinds of method is easy to operate, low cost, high efficiency, and can be widely used. Graphene based materials as a new type of composite material, because of its large surface area, excellent electronic transmission performance, green cheap and other advantages, by the majority of researchers of all ages, has been widely used in photocatalytic degradation and adsorption fields. Based on this, this paper first made of graphite oxide prepared by amine modified Qiu Jiyi Graphene (GO-SH), and Fe3O4 on the surface of GO-SH nanoparticles by GO-SH-/Fe3O4 load magnetic materials, and studied the properties of GO-SH/Fe3O4 adsorption of Ag+ in aqueous solution; a one-step hydrothermal method to prepare doped with different proportion of molybdenum disulfide (MoS2) MoS2rRGO composite hydrogel, with emphasis on the MoS2-RGO composite hydrogel of methylene blue (MB) the photocatalytic degradation was also studied, and some electrochemical properties; a one-step hydrothermal method, GO solution, MoS2 solution and chitosan (CS) solution to prepare the GO-MoS2-CS composite hydrogel, the adsorption properties of the composite hydrogels of MB. The main research contents and conclusions of this paper. The first step is as follows: 1., GO was synthesized by the improved Hummers method, and then the reaction with cysteamine and carboxyl groups on graphene, GO-SH. and Fe304 by co precipitation method on the surface of GO-SH load Nanoparticles. Through FT-IR, TGA, TEM and XPS test were used to characterize the GO-SH/Fe3O4 composites. Finally, performance of GO-SH/Fe304 was studied. The results showed that the adsorption of Ag+ GO-SH on the equilibrium adsorption amount of Ag+ was 68.2 Mg - g-1, and unmodified GO the equilibrium adsorption amount of Ag+ was 40.3 Mg - g-1. test the results show that the adsorption effect of GO-SH on the Ag+ than the GO adsorption on Ag+. Moreover, GO-SH/Fe3O4 composite material has good superparamagnetism, which indicates that the GO-SH/Fe3O4 adsorbent can be very convenient for the recovery and treatment of.2. were prepared by redox GO lithium ion intercalation prepared slices of MoS2. MoS2-RGO then the composite hydrogel preparation with different doping proportion by one-step hydrothermal method. Focus on the photocatalytic degradation properties of MoS2-RGO composite hydrogels of MB, and also studied some electrochemical properties. The results showed that Mo S2 and GO in the hydrogel theallotted.MoS2-GO composite hydrogel have good photocatalytic properties of MB solution (60 min degradation rate reached 99%). This is because the introduction of MoS2 increased the number of photogenerated electrons; graphene as a good conductor, can timely transfer light catalytic process the photogenerated electrons, the photogenerated electron hole pairs recombination probability greatly reduces the.3. first, prepared slices of GO and MoS2. and then by one-step hydrothermal method GO solution, MoS2 solution and CS solution to prepare the GO-MoS2-CS composite hydrogel, and the use of FT-IR, SEM, the characterized by TGA and XRD. The adsorption properties of the composite hydrogel of MB solution, the results showed that the GO-MoS2 and GO-MoS2-CS composite hydrogel and the equilibrium adsorption amount of MB was 136.01 mg/g and 206.16 mg/g., which indicates that the GO-MoS2-CS composite hydrogel has better on MB Adsorption performance. After two cycles, the adsorption amount of GO-MoS2-CS composite hydrogel of MB still can reach the initial equilibrium adsorption amount of 73%. due to the photocatalytic performance of MoS2 has, and GO can timely transfer of photogenerated electrons, improve the catalytic performance of MoS2, which makes the compound water gel can be under illumination the degradation of adsorbed MB, instead of the traditional adsorbent to desorption with acid or alkaline solution. The operation is simple and convenient green adsorbent recycling.

【学位授予单位】：安徽大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;O647.33

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