Surface phase transitions at O and CO catalytic reaction on Pd(1 1 1)

• Published in: Catalysis today Vol. 116; no. 1; pp. 62 - 68
• Main Authors: Tornau, E.E., Petrauskas, V., Zvejnieks, G.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 30.07.2006; Elsevier Science
• Subjects: Catalysis; Catalytic reaction; Chemistry; CO oxidation; Exact sciences and technology; General and physical chemistry; Kinetic Monte Carlo method; Pd surface; Phase transitions; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Catalytic reaction; 68.43.Fg; 68.43.Mn; CO oxidation; 68.43.Hn; Phase transitions; 64.60.Cn; Pd surface; Kinetic Monte Carlo method; Heterogeneous catalysis; Monte Carlo method; CO oxidation; Catalytic reaction; Pd surface; Kinetic Monte Carlo method; Phase transitions; 68.43.Fg; 68.43.Hn; 68.43.Mn; 64.60.Cn; Kinetic method; Oxidation
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/j.cattod.2006.02.081

The model has been proposed to simulate numerically the reaction O + CO → CO 2 and occurring phase transitions on Pd(1 1 1) surface. We calculate the phase diagram for this system by kinetic Monte Carlo method. It shows the phase transitions p ( 2 × 2 ) O → 3 × 3 R 30 O ° and p ( 2 × 2 ) O → 3 × 3 R 30 O ° → p ( 2 × 1 ) O with increase of CO coverage for room and intermediate temperatures, respectively, while in the low temperature limit the direct p(2 × 2) O → p(2 × 1) O phase transition is observed. We demonstrate that the reaction rate is the crucial factor determining the occurrence of the p(2 × 1) O phase and vanishing of the 3 × 3 R 30 O ° with decrease of temperature. The results indicate that the reaction proceeds inside both the p(2 × 2) O and 3 × 3 R 30 O ° phases, but on the perimeter of the domains of p(2 × 1) O structure.