A seminar presented an introduction to studies based on models of catalyses and presented results obtained from different areas of research

On 20 April, the physical chemist Hans-Joachim Freund, from the Max- Planck Institute, presented a seminar on heterogeneous catalysis at the Chemical Engineering Department of the Polytechnic School of the University of São Paulo (Poli-USP). This seminar, organised by the Research Centre for Gas Innovation (RCGI), addressed the understanding of the concept of catalysis and, in particular, of heterogeneous catalysis, based on investigations conducted with the use of modelling systems. With the title of “Models for heterogeneous catalysts: an approach at atomic level”, this event was free of charge and open to the general public.

Physical chemists are the forefathers of the chemical model based on a single surface of crystal metal, which has been successful within the scientific community. The increase in complexity of the models which use nanoparticles as their base, like a real case of catalysing metal dispersion, allows the attainment of some important aspects that cannot be covered by models that use only crystals. This is one of the most important features of the interface through particle support.

“We developed strategies to prepare these modelled systems based on crystalline oxide films that are used as support material for nanoparticles made from oxides and from metal, whose geometric structure, morphology, and electronic structure, as also their interaction and reaction with molecules from the gaseous phase, can be studied at atomic level”, Mr Freund explains.

After a general introduction for the study of models used in catalysis processes, the lecturer then presented the results from different research areas: these include terminations of oxide surfaces; morphology in 2D and 3D; and also the geometric and electronic structure of the metal nanoparticles that have been used, considering the reactivity of CO2, as also in bidimensional silicates and aluminosilicates in ordered and vitreous phases.