Our main interests are the rational design of functional porous materials such as metal-organic frameworks or porous polymers with controllable properties. We apply these materials as (photo)catalysts for the transformation of non-activated molecules (CO2, CH4, C-H activation) and strive for a better understanding of photo-activation processes in heterogeneous molecularly defined catalysts and of confinement effects in non-crystalline materials. In particular, we were able to show that the catalytic activity can be explained by the local electron density at the metal coordination site and can be described using the Hammett correlation known from homogeneous catalysis. As a consequence, our work has led to the design of photocatalysts with constant activities over several days.
For the synthesis of the materials, the group combines solvothermal methods and classical organic as well as organometallic reactions. The materials combine the advantages of both heterogeneous and homogeneous catalysts, such as the easy recyclability of solid materials, and the controllability of the local surrounding of the active site. The porous frameworks provide favourable features including high surface area and adjustable pore size allowing for a controlled accessibility of the active site. At the same time, the materials possess all desirable characteristics from molecular catalysts, such as the tuneable ligands of the organometallic complexes and precisely adjustable optoelectronic properties including frontier orbital position as well as band gap.
Our work in constructing such novel multifunctional materials requires in-depth characterisation of their molecular structure. To this end, we combine several advanced characterisation methods including various spectroscopic and X-ray scattering techniques to understand the structure and the activation/reaction mechanisms of the active sites in both crystalline and amorphous materials.
If you are interested in organometallic chemistry, advanced material synthesis, and in learning new characterization techniques and would like to join our group for a Bachelor or Master Thesis, please contact Dr. Wisser by e-mail or just come and see me personally (office CH 22.1.46).
Topics of theses include the synthesis and purification of organometallic precursors as well as the synthesis of new solid catalysts and their application in catalysis with high sustainable potential. The work will also include a combination of various characterization techniques such as solid-state NMR and X-ray scattering techniques.