单壁碳纳米管-金属团簇的限域组装及催化与电化学检测研究

  单壁碳纳米管（SWCNTs）内腔结构明确，可为客体材料提供丰富的附着位点。此外，SWCNTs内腔具有独特的物理化学环境，如超高压、超润滑性质等，为合成新结构的限域组装材料和其性质研究带来更多可能性。

  金属团簇具有原子精确的结构，是良好的催化构效关系的研究模型。然而，金属团簇的结构稳定性和催化活性通常存在竞争关系。因此，如何权衡结构稳定性和催化活性之间的关系，获得高活性、高稳定性的金属团簇催化剂具有重要的基础研究意义。

  本论文中选取了4种金属团簇，基于SWCNTs外壁对金属团簇的保护作用，发展了室温溶液自组装的方法将团簇限域组装在碳管内腔，制备出金属团簇- SWCNTs精准限域的组装体，系统地研究了组装体的电子转移、催化活性、结构稳定性等结构和性质。具体开展了以下工作：

  利用SWCNTs内腔（1-2 nm）与1-2 nm的{Ag9}、{Ag6}、{Cu6-dppe}、{Cu6-dppe}团簇之间完美的尺寸匹配，在SWCNTs内腔可控组装一维排列的金属团簇（记为{Ag9}@SWCNTs、{Ag6}@SWCNTs、{Cu6-dppe}@SWCNTs和{Cu6-dppm}@SWCNTs）。

  进一步系统研究了金属团簇- SWCNTs组装体的催化性能。其中，{Ag9}@SWCNTs在催化还原对硝基苯酚的反应中展现出了优异的活性与耐久性，反应速率3.75 mol/h·g，可循环反应30次。设计了流动式反应器，模拟工业化的流动催化反应，实现了20mg催化剂以99%以上转化率连续转化15 L对硝基苯酚溶液。通过X射线光电子能谱（XPS）表征证实一维密排列的金属团簇向周围SWCNTs管壁传递电子，在碳管表面形成离域电子，从而加速催化反应。

  另一方面，基于{Ag9}@SWCNTs组装体的电化学响应特性，开展过氧化氢电化学检测器的应用研究。电化学性能测试结果表明，在0.2-5 mmol/L过氧化氢浓度范围内，过氧化氢浓度与电流信号呈线性响应关系，表明其具有作为过氧化氢电化学检测器的潜力。

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