Understanding of Ethanol Decomposition on Rh(111) From Density Functional Theory and Kinetic Monte Carlo Simulations
Reaction mechanisms of ethanol decomposition on Rh(1 1 1) were elucidated by means of periodic density functional theory (DFT) calculations and kinetic Monte Carlo (KMC) simulations. We propose that the most probable reaction pathway is via CH{sub 3}CH{sub 2}O* on the basis of our mechanistic study: CH{sub 3}CH{sub 2}OH* {yields} CH{sub 3}CH{sub 2}O* {yields} CH{sub 2}CH{sub 2}O* {yields} CH{sub 2}CHO* {yields} CH{sub 2}CO* {yields} CHCO* {yields} CH* + CO* {yields} C* + CO*. In contrast, the contribution from the pathway via CH{sub 3}CHOH* is relatively small, CH{sub 3}CH{sub 2}OH* {yields} CH{sub 3}CHOH* {yields} CH{sub 3}CHO* {yields} CH{sub 3}CO* {yields} CH{sub 2}CO* {yields} CHCO* {yields} CH* + CO* {yields} C* + CO*. According to our calculations, one of the slow steps is the formation of the oxametallacycle CH{sub 2}CH{sub 2}O* species, which leads to the production of CHCO*, the precursor for C-C bond breaking. Finally, the decomposition of ethanol leads to the production of C and CO. Our calculations, for ethanol combustion on Rh, the major obstacle is not C-C bond cleavage, but the C contamination on Rh(1 1 1). The strong C-Rh interaction may deactivate the Rh catalyst. The formation of Rh alloys with Pt and Pd weakens the C-Rh interaction, easing the removal of C, and, as expected, in accordance with the experimental findings, facilitating ethanol combustion.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
- Sponsoring Organization:
- BNL-OFFICE OF INTELLECTUAL PROPERTY
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 1019526
- Report Number(s):
- BNL-94298-2011-JA; CATTEA; R&D Project: 09-004; TRN: US201116%%534
- Journal Information:
- Catalysis Today, Vol. 165, Issue 1; ISSN 0920-5861
- Country of Publication:
- United States
- Language:
- English
Similar Records
Chemistry of oxygenates on transition metal surfaces: Activation of C- H, C-C, and C-O bonds. Progress report, December 15, 1991
Chemistry of oxygenates on transition metal surfaces: Activation of C- H, C-C, and C-O bonds