About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Discovery and Design of Emerging Materials
|
Presentation Title |
Haber–Bosch Reaction Mechanism and Kinetics on Highly Reactive Iron Surface and Hierarchical High-throughput in Silico Screening Catalyst Design |
Author(s) |
Qi An, Alessandro Fortunelli, William A Goddard |
On-Site Speaker (Planned) |
Qi An |
Abstract Scope |
To discover new alloy catalysts that dramatically improve the efficiency of the Haber–Bosch (HB) process for ammonia synthesis, we employed quantum mechanics to determine the reaction mechanism and free energy reaction barriers for the most highly reactive Fe(111) surfaces under experimental single crystal reaction conditions. We determined the rates for all 10 important surface reactions on both surfaces. Then we used this information in a full kinetic Monte Carlo simulation to determine the kinetics. We predict that the Turn Over Frequency (TOF) for Fe(111) surface is TOF =18.7 s−1 per 2 × 2 surface site for 1.5 Torr NH3 pressure in excellent agreement with experiment. To dramatically improve the efficiency of HB reactions on these highly reactive surfaces, we applied hierarchical high throughput screening approach to sift the promising doping elements on these two highly reactive surfaces. We found several promising dopants that can significantly improve the TOF. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |