First Principles Kinetic Monte CarloSimulations of Oxygen Interaction with     LaMnO3 Perovskite Surface     Ghanshyam Pil...
Oxygen Interactions with Perovskites:                 Applications  Solid oxide fuel cells                                ...
Relevant Elementary Processes                 Molecular adsorption                 Molecular desorption                 Di...
First Principles Thermodynamics               (FPT)                 O covered surface configurations                  O2 co...
First Principles Thermodynamics               (FPT)              Surface Energy                               Oxygen Chemi...
First Principles Thermodynamics                                                                          partialcoverage- ...
Limitations of the FPT approach•Configurational entropy is not taken into account•Treatment of “large” systems may not be p...
Kinetic Monte Carlo Simulations              Method Highlights•DFT fitted 2-D lattice gas Hamiltonian•Lateral interactions ...
Kinetic Monte Carlo Simulations                                           Thermodynamic Phase diagram                     ...
Kinetic Monte Carlo Simulations                             “Metastable” Phase diagrams                               O+O2...
BECATTHANKS!
Upcoming SlideShare
Loading in …5
×

First Principles Thermodynamics and Kinetic Monte Carlo Simulations: A case study of LaMnO3 (001) surface

808 views

Published on

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
808
On SlideShare
0
From Embeds
0
Number of Embeds
14
Actions
Shares
0
Downloads
7
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

First Principles Thermodynamics and Kinetic Monte Carlo Simulations: A case study of LaMnO3 (001) surface

  1. 1. First Principles Kinetic Monte CarloSimulations of Oxygen Interaction with LaMnO3 Perovskite Surface Ghanshyam Pilania and R. Ramprasad Institute of Materials Science, University of Connecticut MRS Fall Meeting 2011 SESSION B10/C6: Joint Session: SOFC Materials Characterization II
  2. 2. Oxygen Interactions with Perovskites: Applications Solid oxide fuel cells NO oxidation Photocatalytic H2O splitting O2 H2 Catalytic H2O H2O Converter O2 Sr doped Triple-phase LaMnO3 boundary O-2 YSZJ. Fleig, Annu. Rev. Mater. Res. 33, 361 (2003). Chang Hwan Kim, et al. Science 327, 1624 (2010) Kudo et al. Chem. Soc. Rev., 2009, 38, 253–278
  3. 3. Relevant Elementary Processes Molecular adsorption Molecular desorption Dissociative adsorption Associative desorption Surface dissociation Surface Association Surface Diffusion
  4. 4. First Principles Thermodynamics (FPT) O covered surface configurations O2 covered surface configurations
  5. 5. First Principles Thermodynamics (FPT) Surface Energy Oxygen Chemical Potential
  6. 6. First Principles Thermodynamics partialcoverage- O2#Condensation## ofatomicO O2#partial#pressure##[log10(p/p0)]6 100#%#O# Clean&surface Temperature)(K)-
  7. 7. Limitations of the FPT approach•Configurational entropy is not taken into account•Treatment of “large” systems may not be practical•Metastability can not be captured•Kinetic aspects
  8. 8. Kinetic Monte Carlo Simulations Method Highlights•DFT fitted 2-D lattice gas Hamiltonian•Lateral interactions between the adsorbates•Activation barriers within DFT nudged elastic band Method•Local environment dependent activation barriers
  9. 9. Kinetic Monte Carlo Simulations Thermodynamic Phase diagram partialcoverage- partialcoverage-O2#Condensation## ofatomicO O2#Condensation## ofatomicO O2#partial#pressure##[log10(p/p0)]6 O2$partial$pressure$$[log10(p/p0)]7 100%$O 100#%#O# 100#%#O# Clean&surface Clean&surface Temperature$(K)7 Temperature)(K)- Saracco, G., Geobaldo, F. (1999). Applied Catalysis B: Environmental.
  10. 10. Kinetic Monte Carlo Simulations “Metastable” Phase diagrams O+O2 partialcoverage- partialcoverage- O2#Condensation## covered ofatomicO O2#Condensation## ofatomicO 100#%#O# 100#%#O# 100%O2 O+O2 Clean surface Clean surface Starting from a clean surface at 100 K and Starting from a clean surface at any given ramping up the temperature at a given temperature and pressure. pressure.R. Spinicci et al. Journal of Molecular Catalysis A: Chemical 197 (2003) 147–155
  11. 11. BECATTHANKS!

×