Trends in methanol decomposition on transition metal alloy clusters from scaling and Brønsted–Evans–Polanyi relationships

Journal Article · Tue May 15 04:00:00 EDT 2012 · Physical Chemistry Chemical Physics. PCCP (Print)

DOI:https://doi.org/10.1039/c2cp00052k· OSTI ID:1053356

Mehmood, Faisal; Rankin, Rees B.; Greeley, Jeffrey; Curtiss, Larry A.

A combination of first principles Density Functional Theory calculations and thermochemical scaling relationships are employed to estimate the thermochemistry and kinetics of methanol decomposition on unsupported subnanometer metal clusters. The approach uses binding energies of various atomic and molecular species, determined on the pure metal clusters, to develop scaling relationships that are then further used to estimate the methanol decomposition thermodynamics for a series of pure and bimetallic clusters with four atoms per cluster. Additionally, activation energy barriers are estimated from Brønsted–Evans–Polanyi plots relating transition and final state energies on these clusters. The energetic results are combined with a simple, microkinetically-inspired rate expression to estimate reaction rates as a function of important catalytic descriptors, including the carbon and atomic oxygen binding energies to the clusters. Finally, based on these analyses, several alloy clusters are identified as promising candidates for the methanol decomposition reaction.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1053356
• Journal Information: Physical Chemistry Chemical Physics. PCCP (Print), Journal Name: Physical Chemistry Chemical Physics. PCCP (Print) Journal Issue: 24 Vol. 14; ISSN 1463-9076; ISSN PPCPFQ
• Publisher: Royal Society of Chemistry
• Country of Publication: United States
• Language: English

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