FWF - heterogene Katalysator - Reactivity and Structure of Heterogeneous Catalyst Systems

A research project is proposed to investigate the chemical and physical properties of prospective heterogeneous catalysts for methanol dehydrogenation, methanol formation from carbon monoxide or carbon dioxide and hydrogen and methanol steam reforming. These reactions are of importance in advanced fuel cells and novel energy generation concepts. In the proposed project the focus will be on model catalysts studied by modern surface science methods in order to gain a basic understanding of the physico- chemical properties of the model catalyst surfaces. The model catalysts investigated will be a Pd(111) Zn surface alloy and a Pd(111) surface decorated with thin ZnO layers. These systems will be studied with atomic scale precision using a surface science approach. The reactivity of the surfaces with respect to methanol dehydrogenation and CO and CO2 hydrogenation will be investigated by reflection absorption infrared spectroscopy (RAIRS), thermal desorption spectroscopy (TDS), temperature programmed reaction spectroscopy (TDR) and kinetic studies under high pressures using an ultra high vacuum chamber connected to an all glass high pressure reaction cell. The structures of the Pd Zn surface alloy and the ZnO Pd system will be explored at the atomic level using scanning tunneling microscopy (STM), low energy electron diffraction (LEED), density functional theory (DFT) and by using carbon monoxide as a probe molecule with RAIRS. The combination of the results from the reactivity studies and from the structural investigations will yield a complete picture of the microscopic processes that influence the mechanism of the model reactions. The proposed research aims to explain the kinetics of the reactions under high pressure by establishing a detailed physico- chemical reaction mechanism from basic surface science results. These results will provide the scientific basis for the knowledge based design of advanced catalyst materials.