Approaching complexity of alkyl hydrogenation on Pd via density-functional modelling
Hristiyan A Aleksandrov1, Sergey M Kozlov, Georgi N Vayssilov
1Departament de Ciència dels Materials i Química Física and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain. haa@chem.uni-sofia.bg.
Physical Chemistry Chemical Physics : PCCP
|August 2, 2017
Summary
This study reveals how subsurface hydrogen, nanoparticle edges, and spectator ethylidyne influence palladium-catalyzed ethyl hydrogenation. These factors are crucial for understanding alkyl hydrogenation on metal surfaces.
Area of Science:
- Surface Science
- Catalysis
- Computational Chemistry
Background:
- Palladium (Pd) is a key catalyst for hydrogenation and dehydrogenation reactions.
- Understanding alkyl hydrogenation on Pd surfaces is crucial for chemical synthesis.
Purpose of the Study:
- To investigate factors affecting ethyl hydrogenation to ethane on Pd surfaces.
- To elucidate the mechanistic details of subsurface hydrogen acceleration.
- To assess the impact of nanoparticle edges and spectator ethylidyne.
Main Methods:
- Density-functional theory (DFT) calculations were employed.
- Analysis of reaction mechanisms on Pd (111) surfaces.
- Investigation of ethyl and butyl hydrogenation processes.
Main Results:
- Subsurface hydrogen significantly accelerates ethyl hydrogenation on Pd (111).
- Nanoparticle edges and spectator ethylidyne influence the hydrogenation barrier.
- Similar interactions govern butyl hydrogenation, indicating broader applicability.
Conclusions:
- Alkyl hydrogenation on Pd is complex and influenced by multiple factors.
- A more realistic description of hydrogenation requires considering subsurface H, edges, and spectators.
- The findings have implications for designing efficient catalytic processes.
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