Our research seeks to determine the propane dehydrogenation (PDH) reaction pathways using various transition-metal cluster catalysts. We are studying the first step of the reaction, in which a C-H bond is broken. This has been previously shown to be the rate-limiting step of the PDH reaction. We are calculating the PDH activation energy (Ea) using the Vienna Ab-Initio Simulation Package (VASP) in conjunction with the nudged elastic band algorithm. Thus far, we have studied Pt, Ta, and Ni clusters ranging in size from 2-10 atoms. Our goal is to better understand the dependence of Ea on metal type and cluster size

Bradash, Sarah E.

Fadel, Louis

Hoisington, Andrew D.

Zygmunt, Stan A.

English

ValpoScholar

Valparaiso University
ValpoScholar
Summer Interdisciplinary Research Symposium Office of Sponsored and Undergraduate Research
Summer 7-29-2019
Propane Dehydrogenation Using Transition Metal
Cluster Catalysts
Sarah E. Bradash
Valparaiso University, sarah.bradash@valpo.edu
Andrew D. Hoisington
Ivy Tech Community College - Valparaiso, andrew.hoisington1@gmail.com
Stan A. Zygmunt
Valparaiso University, Stan.Zygmunt@valpo.edu
Louis Fadel
Ivy Tech Community College - Valparaiso, lfadel@ivytech.edu
Follow this and additional works at: https://scholar.valpo.edu/sires
This Poster Presentation is brought to you for free and open access by the Office of Sponsored and Undergraduate Research at ValpoScholar. It has been
accepted for inclusion in Summer Interdisciplinary Research Symposium by an authorized administrator of ValpoScholar. For more information, please
contact a ValpoScholar staff member at scholar@valpo.edu.
Recommended Citation
Bradash, Sarah E.; Hoisington, Andrew D.; Zygmunt, Stan A.; and Fadel, Louis, "Propane Dehydrogenation Using Transition Metal
Cluster Catalysts" (2019). Summer Interdisciplinary Research Symposium. 58.
https://scholar.valpo.edu/sires/58
• VASP implements DFT and the NEB algorithm to calculate 
minimum energy path between known reactants and products
• The NEB algorithm functions by adding spring forces along the 
band between images and by projecting out the component of 
the force due to the potential perpendicular to the band
• We use a total of 7 images (5 intermediate structures) to model 
the reaction path
Propane Dehydrogenation Using Transition Metal Cluster Catalysts
Sarah Bradash, Andrew Hoisington*, Louis Fadel*, Stan Zygmunt
Valparaiso University Department of Physics and Astronomy, *Ivy Tech Community College
Abstract
Our research seeks to determine the propane dehydrogenation 
(PDH) reaction pathways using various transition-metal cluster 
catalysts. We are studying the first step of the reaction, in which a 
C-H bond is broken. This has been previously shown to be the rate-
limiting step of the PDH reaction. We are calculating the PDH 
activation energy (Ea) using the Vienna Ab-Initio Simulation 
Package (VASP) in conjunction with the nudged elastic band 
algorithm. Thus far, we have studied Pt, Ta, and Ni clusters ranging 
in size from 2-10 atoms. Our goal is to better understand the 
dependence of Ea on metal type and cluster size.
Computational Procedure
Conclusions
Acknowledgements
• Indiana Space Grant Consortium 
• Valparaiso University Dept. of Physics and Astronomy
• Prof. Zygmunt
NEB Calculation Procedure Graphene-Supported Pt Clusters
• Use Vienna Ab-Initio Simulation Package (VASP) which 
implements density functional theory (DFT) to optimize the 
reactant and product structures
• Use the nudged elastic band (NEB) algorithm to calculate 
reaction pathways for the first step of PDH reaction: C-H bond 
cleavage
• Calculate Ea  for each TM by subtracting the initial energy from 
the transition state energy  
• Ea is dependent on spin state, metal type, and size of cluster
• Spin state crossing occurs for some clusters
• No clear dependence of Ea on ΔE exists for both Ni and Pt, 
contrary to BEP principle
Spin State Crossing
• Spin state crossing 
occurs in some 
structures
• Position at which the 
crossing occurs is 
currently unknown
NEB Algorithm
• Each structure was initially optimized as an isolated TM cluster, then a propane 
molecule was added to begin NEB calculation
• Each NEB calculation maps the energetic pathway of the first step of the PDH 
reaction (C-H bond cleavage)
• Our goal: calculate Ea and investigate correlations with reaction energies and TM 
characteristics
Dependence of Ea on Cluster Size and ΔE
• Ea varies according to cluster size, but not in a linear fashion
• No linear relation between Ea and ΔE; Bell-Evans-Polanyi (BEP) principle does not 
hold for these results
• No clear trend between Ea and ΔE
• Ea depends on cluster size and is a 
minimum for Pt4
• Local geometry of interacting Pt 
atom may influence catalytic activity
-94.30
-94.10
-93.90
-93.70
-93.50
-93.30
-93.10
0 1 2 3 4 5 6
En
e
rg
y 
(e
V
)
Image Number
Ni10 + C3H8 NEB Reaction Path
-62.9
-62.8
-62.7
-62.6
-62.5
-62.4
-62.3
-62.2
-62.1
-62.0
0 1 2 3 4 5 6
En
e
rg
y 
(e
V
)
Image Number
Pt2 + C3H8 NEB Pathway
Singlet
Triplet
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
-0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60
E a
(e
V
)
ΔE (eV)
Ni
Pt
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
2 3 4 5 6 7 8 9 10
E a
(e
V
)
Number of Atoms N
Ni
Pt


Propane Dehydrogenation Using Transition Metal Cluster Catalysts

Valparaiso University

Valparaiso UniversityValpoScholarSummer Interdisciplinary Research Symposium Office of Sponsored and Undergraduate ResearchSummer 7-29-2019Propane Dehydrogenation Using Transition MetalCluster CatalystsSarah E. BradashValparaiso University, sarah.bradash@valpo.eduAndrew D. HoisingtonIvy Tech Community College - Valparaiso, andrew.hoisington1@gmail.comStan A. ZygmuntValparaiso University, Stan.Zygmunt@valpo.eduLouis FadelIvy Tech Community College - Valparaiso, lfadel@ivytech.eduFollow this and additional works at: https://scholar.valpo.edu/siresThis Poster Presentation is brought to you for free and open access by the Office of Sponsored and Undergraduate Research at ValpoScholar. It has beenaccepted for inclusion in Summer Interdisciplinary Research Symposium by an authorized administrator of ValpoScholar. For more information, pleasecontact a ValpoScholar staff member at scholar@valpo.edu.Recommended CitationBradash, Sarah E.; Hoisington, Andrew D.; Zygmunt, Stan A.; and Fadel, Louis, "Propane Dehydrogenation Using Transition MetalCluster Catalysts" (2019). Summer Interdisciplinary Research Symposium. 58.https://scholar.valpo.edu/sires/58• VASP implements DFT and the NEB algorithm to calculate minimum energy path between known reactants and products• The NEB algorithm functions by adding spring forces along the band between images and by projecting out the component of the force due to the potential perpendicular to the band• We use a total of 7 images (5 intermediate structures) to model the reaction pathPropane Dehydrogenation Using Transition Metal Cluster CatalystsSarah Bradash, Andrew Hoisington*, Louis Fadel*, Stan ZygmuntValparaiso University Department of Physics and Astronomy, *Ivy Tech Community CollegeAbstractOur research seeks to determine the propane dehydrogenation (PDH) reaction pathways using various transition-metal cluster catalysts. We are studying the first step of the reaction, in which a C-H bond is broken. This has been previously shown to be the rate-limiting step of the PDH reaction. We are calculating the PDH activation energy (Ea) using the Vienna Ab-Initio Simulation Package (VASP) in conjunction with the nudged elastic band algorithm. Thus far, we have studied Pt, Ta, and Ni clusters ranging in size from 2-10 atoms. Our goal is to better understand the dependence of Ea on metal type and cluster size.Computational ProcedureConclusionsAcknowledgements• Indiana Space Grant Consortium • Valparaiso University Dept. of Physics and Astronomy• Prof. ZygmuntNEB Calculation Procedure Graphene-Supported Pt Clusters• Use Vienna Ab-Initio Simulation Package (VASP) which implements density functional theory (DFT) to optimize the reactant and product structures• Use the nudged elastic band (NEB) algorithm to calculate reaction pathways for the first step of PDH reaction: C-H bond cleavage• Calculate Ea  for each TM by subtracting the initial energy from the transition state energy  • Ea is dependent on spin state, metal type, and size of cluster• Spin state crossing occurs for some clusters• No clear dependence of Ea on ΔE exists for both Ni and Pt, contrary to BEP principleSpin State Crossing• Spin state crossing occurs in some structures• Position at which the crossing occurs is currently unknownNEB Algorithm• Each structure was initially optimized as an isolated TM cluster, then a propane molecule was added to begin NEB calculation• Each NEB calculation maps the energetic pathway of the first step of the PDH reaction (C-H bond cleavage)• Our goal: calculate Ea and investigate correlations with reaction energies and TM characteristicsDependence of Ea on Cluster Size and ΔE• Ea varies according to cluster size, but not in a linear fashion• No linear relation between Ea and ΔE; Bell-Evans-Polanyi (BEP) principle does not hold for these results• No clear trend between Ea and ΔE• Ea depends on cluster size and is a minimum for Pt4• Local geometry of interacting Pt atom may influence catalytic activity-94.30-94.10-93.90-93.70-93.50-93.30-93.100 1 2 3 4 5 6Energy (eV)Image NumberNi10 + C3H8 NEB Reaction Path-62.9-62.8-62.7-62.6-62.5-62.4-62.3-62.2-62.1-62.00 1 2 3 4 5 6Energy (eV)Image NumberPt2 + C3H8 NEB PathwaySingletTriplet0.000.100.200.300.400.500.600.700.800.90-0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60E a(eV)ΔE (eV)NiPt0.000.100.200.300.400.500.600.700.800.902 3 4 5 6 7 8 9 10E a(eV)Number of Atoms NNiPt

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Propane Dehydrogenation Using Transition Metal Cluster Catalysts

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