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N. Barrabés-Rabanal:
"Creating Atomically Designed Catalysts by Metal Nanoclusters";
Hauptvortrag: Seminar ICIQ Institute, Tarragona (Spain); 15.11.2018.

To understand and control the catalytic performance of nanoparticles at molecular level remains a major challenge. An emerging class of functional nanomaterials consisting of less than 100 atoms, with atomic precision, well-defined molecular structure and unexpected catalytic and intrinsically chiral properties are the ligand protected metal nanoclusters. These vary depending on the metal core composition and ligand structure. The application of monolayer protected metal nanoclusters is arising in several fields other than catalysis, like energy, sensing, electronics, bioimaging or therapy. Many of them involve the deposition of clusters on solid surfaces (supports), thus preserving their properties is crucial for application. Particularly in heterogeneous catalysis, atomically precise gold nanoclusters open new opportunities for accurate studies of size-dependent properties, atomic structure effects and reaction mechanisms. However, fundamental understanding of the cluster-surface interaction, control of the deposition and functionalization is still unclear.
We shed some light on this by in situ spectroscopic studies (FTIR, XAFS, XPS), indicating the strong influence of the cluster structure/composition and support material on their stability and catalytic properties. We studied the influence of doped systems, with metals such as Co, Ag, Pd, Pt or Cu, tuning the properties and reactivity in different reactions in gas and liquid phase. Further tuneability of the cluster properties have been achieved by ligand exchange reactions in solution and on supported clusters, inducing new properties like chirality, a first step of creating heterogeneous enantioselective catalysts.