Director of the Institute for Integrated Catalysis
Johannes' research interests focus broadly on elucidating common principles in catalytic reactions facilitated by molecular, surface model, and complex multi-functional catalysts. Specifically, his team is addressing fundamental aspects of industrially relevant catalyzed reactions to understand the reaction steps on the surface of solid catalysts on an elementary level. This knowledge is used to design and synthesize nanoscopically well-defined chemically functionalized surfaces and materials. The synthesis and modification of the target materials is controlled on the level of the individual chemical reactions during the genesis of the (nanoscopic) particles and the assembly of the pre-functionalized entities.
The materials explored primarily include highly structured micro- and mesoporous materials containing protons, metal ions, metal, and metal-oxide clusters. Advanced characterization methods (in situ X-ray diffraction; X-ray absorption spectroscopy; and infrared, Raman, and inelastic neutron scattering spectroscopy) are used to characterize these materials in stages of preparation and during/after sorption and catalysis. Catalytic target reactions are the low-temperature, acid-catalyzed activation, functionalization, and transformation of alkanes; the oxidative activation of light alkanes, including methane; and the hydrogenation and hydrodefunctionalization of biogenic and fossil feedstocks (such as lignin and aromatic molecules containing oxygen, nitrogen, and sulfur). The elementary steps and selective control of sorption and diffusion in molecular sieves is another significant focus of his work outside the catalysis area.