This release is available in German.
In chemical industry, heterogeneous catalysis is of crucial importance to the manufacture of basic or fine chemicals, in catalytic converters of exhaust gas, or for the chemical storage of solar energy. Scientists of Karlsruhe Institute of Technology (KIT) and Ruhr-Universitt Bochum (RUB) have developed a new infrared spectroscopy method in order to study processes at surfaces of oxides used as catalysts. Their results are published in the renowned Angewandte Chemie journal.
Catalysts support many chemical reactions. In heterogeneous catalysis, the substance used as a catalyst and the reacting substances exist in various phases. Usually, the catalyst is a solid, while the reacting substances are gaseous. At the surface of catalytically active solids, highly complex chemical processes take place. They have to be understood in detail in order to further improve products and reduce costs. The processes are known well for metals. However, conversions at the surface of oxides compounds of metals or nonmetals with oxygen have hardly been studied so far.
The research team of Professor Christof Wll from KIT and Professor Martin Muhler from RUB first studied processes at surfaces of oxide monocrystals and then transferred the findings to powders, the technically most important form of oxide materials. Doing this, they were the first to bridge the gap between fundamental research into reference systems and applied research into real catalysts. A newly developed combination device for infrared spectroscopy (IR) allows for highly precise measurements of the vibration frequency of carbon monoxide. The exact value of this vibration frequency is highly sensitive to defects.
Such defects result from the removal of individual oxygen atoms from oxide materials. "Oxygen defects act as active centers a
|Contact: Monika Landgraf|
Helmholtz Association of German Research Centres