Kinetics, Theory & Mechanisms
Prof. Dr. Evgenii Kondratenko
Prof. Dr. Haijun Jiao

The focus of Topic 02 is on mechanistic and kinetic aspects of heterogeneous, homogeneous, electroand photocatalysis.
The subject of ongoing investigations are various large-scale, future-oriented and sustainable catalytic processes. The main goal is to derive correlations between macroscopic observations in reactors with the microscopic structure of catalytic active sites/phases and reaction microkinetics at as elementary a level as possible.
Several research groups from complementary fields are collaborating to achieve this goal. 

Transient (time-resolved) experiments with isotope-labeled molecules, steady-state kinetic and mechanistic measurements, and spectroscopic catalyst characterization are used to identify individual reaction steps and determine their kinetic parameters. With mathematical modeling and numerical analysis of time-resolved experiments and density functional theory (DFT) calculations, it is possible to obtain nearly elementary kinetic and mechanistic information. The combination provides a very detailed view of the mode of action of a wide variety of catalysts.
One focus is on catalyst development supported by mechanistic and kinetic investigations as well as optimization of reactor operation in order to carry out catalyzed reactions as efficiently as possible.
For this purpose, various techniques and methods are applied and combined. Chemometric methods allow the extraction of pure component spectra and concentration profi les of substrates and products as well as catalyst complexes and intermediates from time-resolved FTIR spectra. These are used for the qualitative description of the reaction network.
An integral part of the Topic‘s research is the combination of kinetic measurements (in situ/operando NMR, UV-Vis spectroscopy, catalytic studies) coordination chemistry studies (NMR, UV-Vis, X-ray), time-resolved product analysis, steady-state isotopic transient kinetic analysis and DFT calculations to elucidate reaction mechanisms and to obtain reaction kinetics.
The establishment of vibrational spectroscopy (such as high pressure in situ spectroscopy) supported by DFT calculations offers the potential to identify catalytically active species and develop kinetics for complex and cluster formation. Simultaneous combination with electrochemistry (for spectrochemistry) provides information on structural changes and charge transfer of reactants.
Collaboration in Topic 02 promotes rationalization of experimental results, based on which suggestions can be made for optimizing reaction conditions, improving reaction sequences, and planning new experiments.