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Benzene adsorption on binary Pt3M alloys and surface alloys: a DFT study
Maarten K Sabbe1, Lucia Laín, Marie-Françoise Reyniers
1Laboratorium voor Chemische Technologie, Universiteit Gent, Krijgslaan 281 S5, B-9000 Gent, Belgium.
Physical Chemistry Chemical Physics : PCCP
|July 2, 2013
Summary
Benzene adsorption on platinum-based alloys was studied for catalyst development. The occupied d-band center effectively predicts adsorption energies, guiding future catalyst design for aromatics hydrogenation.
Area of Science:
- Materials Science
- Physical Chemistry
- Computational Chemistry
Background:
- Catalyst development for aromatics hydrogenation is crucial.
- Understanding benzene adsorption on platinum (Pt) based alloys is key for optimizing catalyst performance.
Purpose of the Study:
- To analyze benzene adsorption on Pt3M/Pt(111) surfaces and Pt3M(111) bulk alloys (M = Fe, Co, Ni, Cu, Pd, Ag, Au).
- To identify descriptors for predicting benzene adsorption energies on bimetallic alloys.
Main Methods:
- Density functional theory (DFT) calculations were performed on 4-layered slabs.
- Segregation effects in the top layers of the alloys were considered.
Main Results:
- Benzene adsorption strength varies depending on the alloy composition and surface structure.
- Pt-skin surfaces show different adsorption sites compared to non-segregating surfaces.
- Adsorption energies are generally weaker on alloy surfaces than on pure Pt(111), except for Pt3Pd.
- The occupied d-band center of the clean catalyst slab correlates well with benzene adsorption energies.
Conclusions:
- The occupied d-band center is a reliable descriptor for predicting benzene adsorption on Pt-based bimetallic alloys.
- This finding aids in the rational design of catalysts for aromatics hydrogenation.
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