Subsurface catalysis-mediated selectivity of dehydrogenation reaction
Weiting Cai1,2, Rentao Mu1,2, Shenjun Zha1,2
1Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Science Advances
|August 15, 2018
Summary
This study developed platinum-skin catalysts with subsurface 3d transition metals for propane dehydrogenation. Modifying subsurface regions significantly impacts selectivity, revealing the crucial role of subsurface atoms in catalytic reactions.
Area of Science:
- Heterogeneous catalysis
- Materials science
- Surface chemistry
Background:
- Catalyst design is complex, especially for multicomponent systems, hindering mechanistic understanding.
- Studying nanoparticle catalysts directly is challenging, despite advances in surface science and simulations.
Purpose of the Study:
- To create well-defined platinum-skin catalysts with subsurface 3d transition metals.
- To investigate the influence of subsurface 3d transition metals on propane dehydrogenation selectivity.
- To correlate catalytic performance with electronic structure changes (d-band center shifting).
Main Methods:
- Facile synthesis of platinum-skin catalysts with varying subsurface 3d transition metals (Fe, Co, Ni).
- Evaluation of catalyst performance in propane dehydrogenation.
- Computational analysis of d-band center shifts.
Main Results:
- Catalysts with both surface and subsurface 3dTMs showed decreased selectivity due to C-C cracking on exposed sites (PtFe > PtCo > PtNi).
- Removing surface 3dTMs significantly increased C3H6 selectivity (Pt < PtNi@Pt < PtCo@Pt < PtFe@Pt).
- Selectivity trends correlated with calculated d-band center shifts.
Conclusions:
- Subsurface catalysis plays a critical role in propane dehydrogenation.
- The electronic properties, specifically the d-band center, are key factors influencing catalytic reactivity.
- Well-defined subsurface modification offers a route to tune catalyst performance.
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