The activities of the group are centered around thin film catalyst models. Such models mimic relevant aspects of a real world catalysts, but have a reduced complexity. That allows us to understand catalytic processes in detail. Central activities of the group are the development of thin film preparation recipes and the study of thermal and electrocatalytic reactions at the thin film / gas or liquid interfaces.
Supported catalysts may be mimicked by deposition of metallic aggregates. Several surface-sensitive experimental methods (XPS, TPD, STEM, EELS, IR surface action spectroscopy) are applied under vacuum conditions and at elevated pressures.
Dr. Earl Davis
Dr. Yun Liu
Dr. Ane Etxebarria
Scanning probe microscopy is applied to investigate surface structures. Sometimes also X-ray based structural methods or I/V-LEED structural analysis may be used.
With XPS the elemental composition of the surface and the electronic structure of the surface atoms is investigated. This may also involve adsorbates and/or deposited aggregates.
HREELS is a method for the study of vibrations and electronic excitations at the surface. It may also reveal relevant information about deposited aggregates and adsorbates. In this method electrons are scattered inelastically at a surface. Hereby the electrons suffer an energy loss which is the desired information.
Surface action spectroscopy is a newly developed vibrational method. The investigated surface is covered with weakly bound atoms (the messengers) which are desorbed when infrared radiation [coming from the free electron laser (FEL) of the Institute] excites a vibration of the surface.