Physics – Chemical Physics
Scientific paper
2011-10-05
Journal of catalysis 280 (2011) 178-195
Physics
Chemical Physics
Scientific paper
10.1016/j.jcat.2011.03.017
We present the results of DFT calculations of free energy profiles along the reaction pathways starting from 50% coverage of MoS2 M-edge and 100% coverage of S-edge by sulfur, and leading to 37% coverage, i.e. creation of anionic vacancies, upon reduction by dihydrogen and production of H2S. Significant entropic and enthalpic corrections to electronic energies are deduced from the sets of normal modes vibration frequencies computed for all stationary and transition states. On that basis, we revisit and discuss the surface phase diagrams for M- and S- edges as a function of temperature, H2 partial pressure and H2S/H2 molar ratio, with respect to ranges of conditions relevant to industrial hydrotreating operations. We show that in such conditions, anionic vacancies on the M-edge, and surface SH groups on the M- and S- edges, may coexist at equilibrium. Moderate activation barriers connect stationary states along all paths explored.
Prodhomme Pierre-Yves
Raybaud Pascal
Toulhoat Hervé
No associations
LandOfFree
Free-energy profiles along reduction pathways of MoS2 M-edge and S-edge by dihydrogen: a first-principles study does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Free-energy profiles along reduction pathways of MoS2 M-edge and S-edge by dihydrogen: a first-principles study, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Free-energy profiles along reduction pathways of MoS2 M-edge and S-edge by dihydrogen: a first-principles study will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-180398