Catalysis research
Time resolved diffraction with relativistic electrons
Catalysis research
The use of high-energy electrons is also proving particularly advantageous for catalysis research. Here, scattering at the electrostatic potential makes it possible to precisely determine the positions of hydrogen atoms for many catalytic processes, such as the ecologically highly relevant process of converting CO2 and H2 into methanol in zeolites. In contrast to laboratory-based ED with 100–300 keV electrons, the greater sample penetration of MeV electrons in combination with the significantly larger sample space allows the use of much more complex sample environments. This makes it possible, for example, to investigate catalysis particles under gas loading and at elevated temperatures under operando conditions. Due to the significantly lower radiation damage compared to X-rays, changes in the samples induced by the investigation itself can be minimized, ultimately yielding more realistic results
High-energy electron diffraction at REGAE allows the positions of hydrogen atoms to be determined very accurately and with anisotropic thermal deflection parameters, as shown here using the example of a hydroxyl group the layered silicate muscovite (left). The freely refined anisotropic thermal replacement parameters obtained with MeV electron diffraction at REGAE (ED) show very good agreement with neutron data (ND) from the literature (right).