Dynamic Nuclear Polarization as a Novel Tool for the Characterization of Surfaces and Interfaces of Catalysts and Hybrid Materials

现代固体材料如催化剂和杂化材料通常在纳米尺度和介观尺度上表现出复杂的层次结构。因此，它们的性质和功能是表面和界面上的过程和相互作用的结果。到目前为止，材料科学家依靠纯粹的探索方法来优化目标材料的性能。量身定制的设计只有基于对原子过程、自组织机制和表面和界面上的主导相互作用的详细了解才有可能。DNP核磁共振波谱提出了一个独特的方式来解决这些问题。由于DNP增强，表面和界面面积可以低至几m2/g，甚至可以选择更重要的表面和界面附近的化学物质，从而从不需要的大块信号中分离出来。在提议的项目中，我们的联盟计划通过将固态DNP核磁共振光谱应用于非均相催化剂和无机-有机杂化材料，在现代材料科学的这一关键方面取得进展。此外，我们的目标是通过开发新的自由基系统，改进极化转移方案，特别是四极核，以及低温宽线探针，使DNP技术更有效。为此，我们组建了一个联盟，结合三个不同领域的互补专业知识，即合成有机化学，固体的EPR和核磁共振波谱。该联盟提供EPR和NMR设备开发仪器的知识，并在表面和界面的EPR和NMR光谱方面经验丰富。

Modern solid materials like catalysts and hybrid materials often exhibit complex hierarchical structures on nano- and mesoscopic length scales. Their properties and functions are thus a consequence of processes and interactions on surfaces and at interfaces. Until now material scientists rely on a purely explorative ap-proach for optimizing targeted material properties. A tailored design will be possible only based on a detailed knowledge about the atomistic processes, the self organisation mechanism and dominating interactions on surfaces and at interfaces. DNP NMR spectroscopy poses a unique way to address such questions. Due to the DNP enhancement surface and interface areas down to a few m2/g can be investigated and even more important surface and interface near chemical species can be selected and thus be separated from the unwanted bulk signals. Within the proposed project our consortium plans to make progress on this crucial aspect of modern material science by applying solid-state DNP NMR spectroscopy to heterogeneous catalysts and inorganic-organic hybrid materials. Furthermore, we aim at making DNP techniques more efficient by developing new radical systems, improved polarisation transfer schemes, especially for quadrupolar nuclei, and a low-temperature wide-line probe. For this we have formed a consortium combining the complementary expertise of three dif-ferent areas, namely synthetic organic chemistry, EPR and NMR spectroscopy of solids. The consortium provides knowledge on developing instrumentation for EPR and NMR equipment and is experienced with EPR and NMR spectroscopy on surfaces and at interfaces.