以苯胺寡聚体纳米线为模板制备金-介孔二氧化硅复合纳米管及其催化性能评价

The research and development of novel catalyst carriers and related loading methods is one of the key issues in catalysis. Inorganic nanotubes have aroused great attention due to their unique structure and property. However, considering the existence of several urgent technical problems, the reports of these nanotubes as carriers to load metal nano-particles are rare. In this project, novel aniline oligomer based organic nanowires synthesized through self-assembly strategy will be conducted as templates to prepare Au-mesoporous SiO2 composite nanotubes with tunable compositions, designable structures, and optimized properties, while the catalytic property of this material will be evaluated as well. The research contents mainly include: (1) regulate the size of aniline oligomer based nanowire templates, and thus realize size control of mesoporous SiO2 nanotubes; (2) fabricate Au-mesoporous SiO2 composite nanotubes and optimize their catalytic properties through structure manipulation. This project will not only enrich the synthetic routes of inorganic nanotubes, broaden the scope of applications, but also offer an effective way to solve the problems during nanoparticle loading treatments and catalytic reactions, such as “easy peel off and loss of catalysts, size growth of nanocrystals, and poor control of both dispersity and loading amount of catalysts”.

研究和开发新型的催化剂载体以及负载方法一直是催化领域的核心问题之一。无机纳米管以其特殊的结构和性能引起了人们的极大关注，但是由于存在若干亟待解决的技术难题，以其为载体材料负载金属纳米粒子制备复合催化剂的报道较少。本项目拟以自组装法合成出的新型苯胺寡聚体有机纳米线为模板制备“组成可调控、结构可设计、性能可优化”的金纳米粒子-介孔二氧化硅复合纳米管，并对材料的催化性能进行评价。研究内容包括：（1）调控苯胺寡聚体模板尺寸，进而实现对介孔二氧化硅纳米管尺寸的控制；（2）制备金纳米粒子-介孔二氧化硅复合纳米管，通过调控结构参数优化其催化性能。该项目不但能够丰富无机纳米管的合成途径，拓展其应用范围，还能为解决金属纳米粒子在负载处理和反应催化过程中存在的“催化剂易脱落流失、晶粒尺寸易生长变大、分散性和负载量难以控制”的问题提供有效方法，具有重要的理论和实际意义。

催化剂是催化反应的核心，研究和开发新的催化剂成为破解化工行业困局的重要途径之一。本项目主要研究了以自组装法合成出的新型苯胺寡聚体有机纳米线为模板制备“组成可调控、结构可设计、性能可优化”的金纳米粒子-介孔二氧化硅复合纳米管，并对材料的催化性能进行评价。我们首先实现了苯胺寡聚体有机纳米线尺寸的成功调控，详细讨论了多种弱相互作用如π-π相互作用、氢键作用、亲水/疏水作用如何协同调控组装过程，解析了相关的物理化学作用机制。通过静电作用在苯胺寡聚体模板表面吸附Au NPs，然后经过正硅酸乙酯（TEOS）水解、煅烧得到了Au-mSiO2复合纳米管材料，详细探讨了有机纳米线模板的表面电荷密度对Au NPs吸附和mSiO2壳层包覆的影响。通过优化反应条件，实现了对mSiO2纳米管的管径、管壁厚度、管壁孔体积以及管壁上吸附的Au NPs的负载量的有效控制。我们进而考察了Au-mSiO2复合纳米材料活性组分Au NPs的催化性能，包括催化活性、循环稳定性等。我们结果表明催化剂具有较高的降解水污染物，4-硝基苯酚的能力，且催化剂能够多次循环使用。