Univ. of Wisconsin, Madison, WI (United States). Dept. of Chemical and Biological Engineering; Department of Chemical and Biological Engineering, University of Wisconsin-Madison
Univ. of Wisconsin, Madison, WI (United States). Dept. of Chemical and Biological Engineering
Iron is the principal catalyst for the ammonia synthesis process and the Fischer–Tropsch process, as well as many other heterogeneously catalyzed reactions. It is thus of fundamental importance to understand the interactions between the iron surface and various reaction intermediates. Here in this paper, we present a systematic study of atomic and molecular adsorption behavior over Fe(110) using periodic, self-consistent density functional theory (DFT-GGA) calculations. The preferred binding sites, binding energies, and the corresponding surface deformation energies of five atomic species (H, C, N, O, and S), six molecular species (NH3, CH4, N2, CO, HCN, and NO), and eleven molecular fragments (CH, CH2, CH3, NH, NH2, OH, CN, COH, HCO, NOH, and HNO) were determined on the Fe(110) surface at a coverage of 0.25 monolayer. The binding strengths calculated using the PW91 functional decreased in the following order: C> CH > N > O > S > NH > COH > CN > CH2 > NOH > OH > HNO > HCO > NH2 > H > NO > HCN > CH3 > CO > N2 > NH3. No stable binding structures were observed for CH4. The estimated diffusion barriers and pathways, as well as the adsorbate-surface and intramolecular vibrational modes of all the adsorbates at their preferred binding sites, were identified. Using the calculated adsorption energetics, we constructed the potential energy surfaces for a few surface reactions including the decomposition of methane, ammonia, dinitrogen, carbon monoxide, and nitric oxide. These potential energy surfaces provide valuable insight into the ability of Fe(110) to catalyze common elementary steps.
@article{osti_1398766,
author = {Xu, Lang and Kirvassilis, Demetrios and Bai, Yunhai and Mavrikakis, Manos},
title = {Atomic and molecular adsorption on Fe(110)},
annote = {Iron is the principal catalyst for the ammonia synthesis process and the Fischer–Tropsch process, as well as many other heterogeneously catalyzed reactions. It is thus of fundamental importance to understand the interactions between the iron surface and various reaction intermediates. Here in this paper, we present a systematic study of atomic and molecular adsorption behavior over Fe(110) using periodic, self-consistent density functional theory (DFT-GGA) calculations. The preferred binding sites, binding energies, and the corresponding surface deformation energies of five atomic species (H, C, N, O, and S), six molecular species (NH3, CH4, N2, CO, HCN, and NO), and eleven molecular fragments (CH, CH2, CH3, NH, NH2, OH, CN, COH, HCO, NOH, and HNO) were determined on the Fe(110) surface at a coverage of 0.25 monolayer. The binding strengths calculated using the PW91 functional decreased in the following order: C> CH > N > O > S > NH > COH > CN > CH2 > NOH > OH > HNO > HCO > NH2 > H > NO > HCN > CH3 > CO > N2 > NH3. No stable binding structures were observed for CH4. The estimated diffusion barriers and pathways, as well as the adsorbate-surface and intramolecular vibrational modes of all the adsorbates at their preferred binding sites, were identified. Using the calculated adsorption energetics, we constructed the potential energy surfaces for a few surface reactions including the decomposition of methane, ammonia, dinitrogen, carbon monoxide, and nitric oxide. These potential energy surfaces provide valuable insight into the ability of Fe(110) to catalyze common elementary steps.},
doi = {10.1016/j.susc.2017.09.002},
url = {https://www.osti.gov/biblio/1398766},
journal = {Surface Science},
issn = {ISSN 0039-6028},
number = {C},
volume = {667},
place = {United States},
publisher = {Elsevier},
year = {2017},
month = {09}}
USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE Office of Science (SC), Biological and Environmental Research (BER)
Contributing Organization:
National Energy Research Scientific Computing Center (NERSC); and the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility at Pacific Northwest National Laboratory (PNNL); the Center for Nanoscale Materials (CNM) at Argonne National Laboratory (ANL)