Sol-gel法制备金属掺杂的多孔硅、铝氧化物复合材料

发布时间：2018-05-19 19:44

  本文选题：溶胶-凝胶法 + 介孔　； 参考：《安徽大学》2011年硕士论文

【摘要】：介孔SiO2材料比表面积较大、孔道大小均匀、孔径可在2nm至50nm范围内连续调节等特性,使其在分离提纯、生物材料、催化、环境、能源、新型组装材料(或作为纳米反应器制备具有特殊光、电、磁等性能的新型纳米材料等)等领域具有多种潜在的用途,尤其是在生物医学方面如蛋白质固定分离、生物芯片、生物传感器、药物的包埋和控释等具有广阔的应用前景。 本论文以高分子化合物为模板剂,采用了溶胶凝胶法(Sol-gel)和溶胶凝胶-水热法合成介孔SiO_2及其金属氧化物掺杂介孔SiO2复合材料,详细研究了高分子模板、掺杂金属、煅烧温度等反应条件对产物孔结构的影响规律,初步探讨了其在吸附去除有机染料方面的应用,论文工作包括以下几部分： 第一章运用高分子化合物聚乙二醇(PEG)作为模板剂,利用Sol-gel法合成出了介孔SiO2以及金属氧化物掺杂的复合材料,主要考察了制备过程中PEG分子量长度、PEG质量、金属掺杂量、煅烧温度等条件对材料孔结构的影响。实验结果表明：可根据PEG的分子量、浓度及链的长短进行调节介孔材料的介相结构,一般来讲PEG分子量对复合材料的孔结构影响不大,材料的SABETa、Vtot数值随着PEG质量的增加而增加；SiO2中由于金属氧化物的掺杂使得复合材料的比表面积孔容和孔径减小,可能是氧化物占据了孔道,形成了Si-O-M化学键,从而提高了材料的热稳定和水热稳定性；另外考察了煅烧温度的影响,温度过低有机物去除不完全,温度过高可能使得硅骨架坍塌,实验证明550℃是最佳煅烧温度。 第二章使用Sol-gel法直接合成了CuO/SiO2复合材料,采用X射线衍射(XRD),N2等温吸附-脱附法,傅立叶变换红外光谱(FT-IR),高分辨透射电镜(HRTEM)等手段对合成的样品进行表征。实验结果表明过渡金属的掺杂引入基本没有改变SiO2的骨架,一部分金属离子进入到Si02骨架中形成了M-O-Si键,形成的CuO晶相小颗粒占据了部分孔道,使得材料的比表面积有所下降。 第三章通过溶胶凝胶-水热法制备了铜的氧化物复合材料,并研究了对有机染料亚甲基蓝的吸附作用。实验结果表明CuO/SiO2多孔复合材料对亚甲基蓝有良好的吸附效果,在吸附剂(Cs-600-6-15-NaOH-11-12h-140)用量是0.015g,体系pH=9,搅拌时间为2h的条件下,对亚甲基蓝的去除率高达97.17%。 实验结果表明,以PEG为模板,通过溶胶凝胶法可以方便地制备出介孔二氧化硅及其金属掺杂的复合材料,通过PEG分子量、添加质量等反应条件可以调节、控制复合材料的孔结构特征,还可以有效地将无机金属氧化物引入到Si02骨架中形成M-O-Si化学键,赋予介孔二氧化硅新的物理化学特性,制备出多功能的介孔复合材料,广泛的应用于吸附、催化等相关领域。
[Abstract]:Mesoporous SiO2 materials have large specific surface area, uniform pore size, continuous adjustment of pore size in the range of 2nm to 50nm and so on, which make them separate and purify, biomaterials, catalysis, environment, energy, etc. Novel assembly materials (or new nanomaterials with special optical, electrical, magnetic properties, etc.) have many potential applications, especially in biomedical fields such as protein fixation and separation, biochips, etc. Biosensors, drug encapsulation and controlled release have broad application prospects. In this paper, the mesoporous SiO_2 and its metal-oxide doped mesoporous SiO2 composites were synthesized by sol-gel method and sol-gel hydrothermal method with polymer compounds as template. The effect of calcination temperature on the pore structure of the product is discussed. The application of the product in adsorption and removal of organic dyes is discussed. The work of this paper includes the following parts: In the first chapter, the mesoporous SiO2 and metal oxide doped composites were synthesized by Sol-gel method using polyethylene glycol (PEG) as template. The molecular weight of PEG and the amount of metal doped were investigated. The influence of calcination temperature on the pore structure of the material. The experimental results show that the mesophase structure of mesoporous materials can be adjusted according to the molecular weight, concentration and chain length of PEG. Generally speaking, the molecular weight of PEG has little effect on the pore structure of composites. The Vtot value of SABETaI increases with the increase of PEG mass. The specific surface area pore volume and pore size decrease due to the doping of metal oxides in SiO2. It may be that the oxides occupy the pore channels and form the Si-O-M chemical bond. The thermal stability and hydrothermal stability of the materials were improved, and the effect of calcination temperature was investigated. The temperature was too low to remove organic matter completely, and the silicon skeleton might collapse when the temperature was too high. It was proved that 550 鈩，

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