skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Nitrogen electroreduction and hydrogen evolution on cubic molybdenum carbide: a density functional study

Abstract

We report in this paper a density functional theory study of the nitrogen electroreduction and hydrogen evolution reactions on cubic molybdenum carbide (MoC) in order to investigate the viability of using this material as an electro-catalyst for ammonia synthesis. Free energy diagrams for associative and dissociative Heyrovsky mechanisms showed that nitrogen reduction on cubic MoC(111) can proceed via an associative mechanism and that small negative potentials of -0.3 V vs. standard hydrogen electrode can onset the reduction of nitrogen to ammonia. Kinetic volcano plots for hydrogen evolution showed that the MoC[110] surface is expected to have a high rate for the hydrogen evolution reaction, which could compete with the reduction of nitrogen on cubic MoC. The comparison between the adsorption energies of H-adatoms and N-adatoms also shows that at low potentials adsorption of hydrogen atoms competes with nitrogen adsorption on all the MoC surfaces except the MoC(111) surface. Finally, the hydrogen evolution and accumulation of H-adatoms can be mitigated by introducing carbon vacancies i.e. increasing the ratio of metal to carbon atoms, which will significantly increase the affinity of the catalytic surface for both nitrogen molecules and N-adatoms.

Authors:
ORCiD logo [1]; ORCiD logo [2]
  1. Univ. of New Mexico, Albuquerque, NM (United States). Chemical and Biological Engineering Dept. Center for Micro-Engineered Materials; Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Univ. of New Mexico, Albuquerque, NM (United States). Chemical and Biological Engineering Dept. Center for Micro-Engineered Materials; Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Advanced Research Projects Agency - Energy (ARPA-E); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1440453
Alternate Identifier(s):
OSTI ID: 1437516
Report Number(s):
LA-UR-18-21724
Journal ID: ISSN 1463-9076
Grant/Contract Number:  
AC52-06NA25396; AR 1261-4005; AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Chemistry Chemical Physics. PCCP (Print)
Additional Journal Information:
Journal Volume: 20; Journal Issue: 21; Journal ID: ISSN 1463-9076
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Material Science

Citation Formats

Matanovic, Ivana, and Garzon, Fernando H. Nitrogen electroreduction and hydrogen evolution on cubic molybdenum carbide: a density functional study. United States: N. p., 2018. Web. doi:10.1039/C8CP01643G.
Matanovic, Ivana, & Garzon, Fernando H. Nitrogen electroreduction and hydrogen evolution on cubic molybdenum carbide: a density functional study. United States. doi:10.1039/C8CP01643G.
Matanovic, Ivana, and Garzon, Fernando H. Thu . "Nitrogen electroreduction and hydrogen evolution on cubic molybdenum carbide: a density functional study". United States. doi:10.1039/C8CP01643G. https://www.osti.gov/servlets/purl/1440453.
@article{osti_1440453,
title = {Nitrogen electroreduction and hydrogen evolution on cubic molybdenum carbide: a density functional study},
author = {Matanovic, Ivana and Garzon, Fernando H.},
abstractNote = {We report in this paper a density functional theory study of the nitrogen electroreduction and hydrogen evolution reactions on cubic molybdenum carbide (MoC) in order to investigate the viability of using this material as an electro-catalyst for ammonia synthesis. Free energy diagrams for associative and dissociative Heyrovsky mechanisms showed that nitrogen reduction on cubic MoC(111) can proceed via an associative mechanism and that small negative potentials of -0.3 V vs. standard hydrogen electrode can onset the reduction of nitrogen to ammonia. Kinetic volcano plots for hydrogen evolution showed that the MoC[110] surface is expected to have a high rate for the hydrogen evolution reaction, which could compete with the reduction of nitrogen on cubic MoC. The comparison between the adsorption energies of H-adatoms and N-adatoms also shows that at low potentials adsorption of hydrogen atoms competes with nitrogen adsorption on all the MoC surfaces except the MoC(111) surface. Finally, the hydrogen evolution and accumulation of H-adatoms can be mitigated by introducing carbon vacancies i.e. increasing the ratio of metal to carbon atoms, which will significantly increase the affinity of the catalytic surface for both nitrogen molecules and N-adatoms.},
doi = {10.1039/C8CP01643G},
journal = {Physical Chemistry Chemical Physics. PCCP (Print)},
issn = {1463-9076},
number = 21,
volume = 20,
place = {United States},
year = {2018},
month = {4}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 3 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Generalized Gradient Approximation Made Simple
journal, October 1996

  • Perdew, John P.; Burke, Kieron; Ernzerhof, Matthias
  • Physical Review Letters, Vol. 77, Issue 18, p. 3865-3868
  • DOI: 10.1103/PhysRevLett.77.3865

Computational high-throughput screening of electrocatalytic materials for hydrogen evolution
journal, October 2006

  • Greeley, Jeff; Jaramillo, Thomas F.; Bonde, Jacob
  • Nature Materials, Vol. 5, Issue 11, p. 909-913
  • DOI: 10.1038/nmat1752

Projector augmented-wave method
journal, December 1994


From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999


Ab initiomolecular dynamics for liquid metals
journal, January 1993


Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
journal, July 1996


Special points for Brillouin-zone integrations
journal, June 1976

  • Monkhorst, Hendrik J.; Pack, James D.
  • Physical Review B, Vol. 13, Issue 12, p. 5188-5192
  • DOI: 10.1103/PhysRevB.13.5188

Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set
journal, October 1996


Ab initio molecular-dynamics simulation of the liquid-metal�amorphous-semiconductor transition in germanium
journal, May 1994