CH4 oxidations by Pd-based catalyst with and without oxygen coating were studied using ReaxFF Molecular Dynamics simulations. Results revealed the complete dynamic process of the catalytic oxidations at the atomic delineating the underlying mechanisms both qualitatively and quantitatively. Oxygen molecules were easier to be adsorbed on both bare and oxygen-coated Pd surfaces than CH4. Comparison of the adsorptive dissociation of CH4 over Pd nanoparticles with various levels of oxygen coverage showed that it was easier for the adsorptive dissociation of CH4 on oxygen-coated Pd nanoparticles than on bare ones at low temperatures. The CH4 dissociation rate increased with increasing temperature and is sensitive to the level of oxygen coverage on the surface. Additionally the activation energies for the adsorptive dissociation of CH4 were determined by fixed-temperature simulations from 400 K to 1000 K through the changes of CH4 concentration.
All Science Journal Classification (ASJC) codes
- General Chemical Engineering
- Mechanical Engineering
- Physical and Theoretical Chemistry