Trends in Formic Acid Decomposition on Model Transition Metal Surfaces: A Density Functional Theory Study

Journal Article · Fri Dec 05 04:00:00 EST 2014 · ACS Catalysis, 4(12):4434–4445

DOI:https://doi.org/10.1021/cs500737p· OSTI ID:1222119

Herron, Jeffrey A.; Scaranto, Jessica; Ferrin, Peter A.; Li, Sha; Mavrikakis, Manos

We present a first-principles, self-consistent periodic density functional theory (PW91-GGA) study of formic acid (HCOOH) decomposition on model (111) and (100) facets of eight fcc metals (Au, Ag, Cu, Pt, Pd, Ni, Ir, and Rh) and (0001) facets of four hcp (Co, Os, Ru, and Re) metals. The calculated binding energies of key formic acid decomposition intermediates including formate (HCOO), carboxyl (COOH), carbon monoxide (CO), water (H2O), carbon dioxide (CO2), hydroxyl (OH), carbon (C), oxygen (O), and hydrogen (H; H2) are presented. Using these energetics, we develop thermochemical potential energy diagrams for both the carboxyl-mediated and the formate-mediated dehydrogenation mechanisms on each surface. We evaluate the relative stability of COOH, HCOO, and other isomeric intermediates (i.e., CO + OH, CO2 + H, CO + O + H) on these surfaces. These results provide insights into formic acid decomposition selectivity (dehydrogenation versus dehydration), and in conjunction with calculated vibrational frequency modes, the results can assist with the experimental search for the elusive carboxyl (COOH) surface intermediate. Results are compared against experimental reports in the literature.

• 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: 1222119
• Journal Information: ACS Catalysis, 4(12):4434–4445, Journal Name: ACS Catalysis, 4(12):4434–4445
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory