The overarching goal of our research is to achieve a fundamental understanding of the processes occurring during (photo-)catalytic reactions on model catalysts. This knowledge may help to develop better catalysts for improved energy and fuel production.
We study the interaction of molecules with oxide surfaces such as titanium dioxide and iron oxide under well-controlled conditions by means of scanning tunneling microscopy (STM), temperature-programmed desorption (TPD) and photoelectron spectroscopy (PES). We use simplified model catalysts, either oxide single crystals or oxide thin films grown on a metal substrate. The high resolution of the STM combined with the sample-averaging spectroscopies allows us to identify the active sites of catalytic and photocatalytic reactions. Ideally, in-situ imaging of the reactions will offer a dynamic view of the behavior of reactants on an atomic-molecular level.
Understanding the active sites of catalytic and photocatalytic reactions is key to material design and modifications that will lead to better (photo-)catalysts. Without such research, trial-and error methods would dominate the field and an understanding of what makes a good catalyst would be lacking.
Future research initiatives include the study of the water-TiO2 (anatase) interface as well as the ethanol-TiO2 interface both in the dark and under the influence of ultraviolet light.