22 research outputs found
Site-dependent reactivity of MoS2 nanoparticles in hydrodesulfurization of thiophene
N.S. and J.R.F. performed the experiments. N.S. analyzed the experimental data. S.R.
performed the theory. J.V.L. and M.M. planned and organized the studies. N.S. wrote the
first draft. J.V.L. wrote the final version. All authors contributed to the final version of the
manuscript.The catalytically active site for the removal of S from organosulfur compounds in catalytic
hydrodesulfurization has been attributed to a generic site at an S-vacancy on the edge of
MoS2 particles. However, steric constraints in adsorption and variations in S-coordination
means that not all S-vacancy sites should be considered equally active. Here, we use a
combination of atom-resolved scanning probe microscopy and density functional theory to
reveal how the generation of S-vacancies within MoS2 nanoparticles and the subsequent
adsorption of thiophene (C4H4S) depends strongly on the location on the edge of MoS2.
Thiophene adsorbs directly at open corner vacancy sites, however, we find that its adsorption
at S-vacancy sites away from the MoS2 particle corners leads to an activated and concerted
displacement of neighboring edge S. This mechanism allows the reactant to self-generate a
double CUS site that reduces steric effects in more constrained sites along the edge.The U.S. Department of Energy (DOEBasic Energy Sciences (BES)Office of Chemical SciencesCatalysis Science Program. DE‐FG02‐05ER15731National Energy Research Scientific Computing Center
(NERSC)Center for Nanoscale Materials (CNM)Argonne National
Laboratory (ANL)Department of Energy,
Office of Science, under contracts DE‐AC02‐06CH11357 and DE‐AC02‐05CH1123