QM2 - Quantum Matter and Materials | January 20, 14:30

Nanocluster arrays: from model catalysis to nanographene

Christian Papp

The talk will cover spectroscopic investigations on the catalytic properties of iron nanoparticle arrays and details on the formation of nanographene in nano-heterostructures. The increased complexity of real-life catalysts as compared to surface science leads to the “materials gap”. To close this gap, studies of adsorption and reaction experiments on nanoparticles supported on 2D materials were conducted under in situ conditions with the particular aim to elucidate the reactivity of such more “realistic” nanoparticles. It is shown that the use of a quantitative spectroscopy allows for gaining a detailed insight even to these complex systems, thereby facilitating a further step into bridging the materials gap from fundamental science to applied sciences. The use of the 2D materials as a chemically “innocent” substrate gives the intriguing possibility to study the system without the additional influence of side processes such as spill over and reverse spill over. Such studies allow for characterization of novel cluster systems towards their reactivity and adsorption behavior, e.g. for iron nanoclusters with the probe molecule CO. Such reactivity studies are also possible for the more complex chemistry of ethylene on Pt nanoclusters where detailed insights to the reaction pathway become available. Thereby the changes when going from single crystals to nanoclusters become evident. As a second topic, the formation of van-der-Waals nano-heterostructures is discussed. Insights from spectroscopic and microscopic studies allowed us to characterize the individual preparation steps and the final nano-heterostructure consisting of graphene / metal / h-BN stack. Experiments with different cluster sizes are shown to obtain insights to the pore filling of the h-BN substrate. This gives a direct measure of the agglomeration of the nanoclusters during preparation. Literature F. Düll, et al. ACS Applied Nano Materials 2 (2019) 7019. F. Düll, et al. Journal of Chemical Physics 152 (2020) 224710. F. Düll, et al. Physical Chemistry Chemical Physics 21 (2019) 21287.


Friedrich-Alexander-Universität Erlangen-Nürnberg
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