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Lowering the Activation Energy of Fischer Tropsch Reactions through
CoRu Core-Shell Catalysts
Mentor: Dr. Daniela Mainardi REU Student: Tosin Oyeleke
Finding the Best Catalyst for Liquid Fuel Production
Mentor: Dr. Daniela Mainardi REU Student: Tosin Oyeleke
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Methods of Producing Fuel
Fuel Production
Indirect Direct Biofuel Processes
Fischer Tropsch
Methanol Synthesis
Pyrolysis & Carbonation
Hydrogenation
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What is the Fischer Tropsch Process?
CO + H2 Catalyst Fuel + H2O
Ivo Filot et. al The Fischer Tropsch Reaction Institute of Complex Molecular Systems
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…Why Computational Modeling?
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Methodology Used
Building Catalyst Nanocluster
Nanocluster Optimization
CO docking
Energy Barrier Calculation
Molecular Dynamics
Building Catalyst Nanoclusters
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Co Core Ru Core
10% 50% 80% 10% 50% 80% 10% 50% 80% 10% 50% 80% 10% 50% 80% 10% 50% 80%
13 atoms 19 atoms 38 atoms 13 atoms 19 atoms 38 atoms
Co
Ru
-133.97eV -135.01eV -120.31eV -141.80eV -121.64eV -120.31eV
Nanocluster Optimization
Docking of CO Molecules on the Shell
Top Bridge Hollow
O C Co
Daniela Mainardi Fischer-Tropsch Reactions for Fuel Production May 16,2012 8/27/13 8
Top Bridge Hollow
38 Atoms 50%
N/A
19 Atoms 50%
Docking of CO Molecules on Ru Core Nanoclusters
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13 Atoms 10%
N/A
-2.61 eV -2.98 eV -2.99 eV -1.37 eV -2.24 eV -1.96 eV -2.22 eV
-1.64 eV
38 Atoms 50% Top Bridge Hollow
19 Atoms 80%
Docking of CO Molecules on Co Core Nanoclusters
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13 Atoms 80%
N/A
-2.56 eV -3.66 eV
N/A
-1.82 eV 0.06 eV -1.24 eV -0.24 eV
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Binding Energies for Optimized CO Docked Molecules Co Core
-4
-3
-2
-1
0
1
Bin
ding
Ene
rgy
(eV
)
19atoms80% 13atoms 80% 38atoms50%
Top Bridge Hollow
LOWEST BINDING ENERGY
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Binding Energies for Optimized CO Docked Molecules Ru Core
-4
-3
-2
-1
0
Bin
ding
Ene
rgy
(eV
)
13atoms 10% 19atoms50% 38atoms50%
Top Bridge Hollow
LOWEST BINDING ENERGY
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Transition State: Energy Barriers for 13 Atoms
Reaction Pathway
Ene
rgy
(eV
)
Reactants
3.74 eV
0.17eV
Products Ea
80% Co Core Top
10% Ru Core Top
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Molecular Dynamics of 38 Atoms 50% Bridge Co Core at 25oC
FAILED
Conclusion: Favorable Adsorption Site
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-2.61 eV -2.98 eV -2.99 eV
-3.66 eV
Top Bridge Hollow
-2.56 eV
Ru Core: Co Core:
C H O Co Ru
Future Work
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• Complete transition states • Run Molecular Dynamics at 200oC • Try other CO docking positions
Ea
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My Experience so Far
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My Experience so Far
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Acknowledgement
Dr. Daniela Mainardi Fernando Soto and Suraj Gwajali Ms. Alicia Boudreaux
• Op#ons: solar energy, wind,3s • Introduce the two core-‐shell structures. • Why 3s? and benefits • The bo@leneck of using 3s • Our approach to fix bo@leneck • Our methodology and results • Graph of binding energies (showing the most pos#ve one) Equa#on of binding energy
• Graph of transi#on enrgies.
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Literature Comparison of Bond Lengths
Find • Hydrogen bond length h@p://itchem.com/calculated___and__experimental__dat
• CO bond length • Water Bond length • Co-‐C Bond Length h@p://sta#c.msi.umn.edu/rreports/2007/55.pdf • Co-‐Co Bond Length • Co-‐Ru Bond Length
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