Towards a comprehensive and predictive theory of catalysis based on simple structure-activity relations

Samenvatting

Sustainable progress can only be ensured by using efficient, clean and inexpensive energy sources. Catalysis-based technologies are appealing, as they can effectively transform renewable energy into chemical bonds and vice versa. The challenge lies in finding suitable catalysts for these transformations. An important method is the computational design of materials based on scaling relations, which are correlations between adsorption-related energetics on surfaces that allow creating activity plots.
However, the method has two shortcomings: the relationship between activity and surface morphology/composition is not evident, and its use is not straightforward when scaling relations are not linear. In previous work, I have shown that this exceptional behavior is displayed by some near-surface alloys (NSAs), which are excellent catalysts for reactions such as the oxygen reduction reaction (ORR), CO oxidation and water-gas shift. Thus, NSAs are technologically interesting but methodologically challenging materials.
I propose to develop a pioneering methodology for the design of NSA catalysts based on two simple but powerful concepts: number of valence electrons and coordination number. The method will provide an unprecedented connection between electronic/geometric structure and catalytic activity. The proofs of concept will be four electrochemical reactions essential for renewable energies and environmental damage mitigation: the ORR and the oxidation and reduction of CO, paramount in fuel cells and electrolyzers, and nitrate reduction, crucial for pollution control.
I will create a large dataset of adsorption-related energetics for the proof-of-concept reactions through state-of-the-art DFT calculations. Moreover, I will analyze the data with the proposed descriptors, giving rise to scaling-free structure/activity diagrams. These will help find suitable materials and facets, and the best candidates will be tested experimentally in the host group. This project will make a significant step forward in our understanding of catalysis by combining the power of computational chemistry with more intuitive chemical concepts and experimental validation.

Kenmerken

Projectnummer

722.014.009

Hoofdaanvrager

Dr. F. Calle Vallejo

Verbonden aan

Universiteit Leiden, Faculteit der Wiskunde en Natuurwetenschappen, Leiden Institute of Chemistry

Uitvoerders

Dr. F. Calle Vallejo

Looptijd

01/04/2015 tot 31/03/2018