Different components increase the capacities of tiny particles
All football experts know that to be successful a team needs players with different skills. A similar rule evidently applies to complex chemical processes that can be accelerated with catalytic materials. These catalysts are composed of a range of components that are only a few nanometres in size and whose interaction is of central importance. If a team is working properly it fosters abilities that go far beyond those of its individual components.
This has now been proven by a Friedrich-Alexander University of Erlangen-Nuremberg (FAU) research group headed by Jörg Libuda, professor for Physical Chemistry, as part of an international cooperation project with working groups from Barcelona, Prague and Trieste. The results of this project, which has received partial funding from the Erlangen Engineering of Advanced Materials excellence cluster, were published in the Nature Materials journal (DOI 10.1038/NMAT2976).
“Black magic” in catalyst production
Heterogeneous catalysed processes play a decisive role in energy-efficient and resource-saving production of most industrially-produced chemicals, and in key energy and environmental technologies of the future. In this context, the word “heterogeneous” means that the catalyst and the reacting materials are present in different aggregate states: either solid, liquid or gas. Most of the materials used in this project are highly complex. It has therefore proven unusually difficult to gain an insight into how these materials work. That is why, in most cases, heterogeneous catalysts are optimised using purely empirical procedures – trial and error – leading to their production often being called “black magic”.
The international research team has now managed to produce simplified model systems for these sorts of catalysts. On the one hand, these pave the way for research using cutting-edge experimental procedures, e.g. what is known as synchrotron radiation, and on the other, the application of modern, theoretical, quantum mechanic methods. When combined, theory and experiments make it possible to garner a detailed insight into how these complex materials work.
It has thus become clear that it is precisely the complex structure that allows new properties to be created: the catalysts are made of oxide and metal particles only a few nanometres in size but that must be brought into close contact. The special chemical reactivity comes from the relationship between the different individual components. These oxygen species, which are highly reactive when combined, only interact generating entirely new reactions when in the form of tiny nanoparticles.
Further information for the media:
Prof. Dr. Jörg Libuda