First Principles Study of Low Miller Index RuS2 Surfaces in Hydrotreating Conditions

摘要: Density functional theory (DFT) calculations combined with surface thermodynamic arguments and the Gibbs-Curie-Wulff equilibrium morphology formalism have been employed to explore effect of reaction conditions, temperature (T), gas-phase partial pressures (p h2 p h2s ) on stability low Miller index ruthenium sulfide (RuS 2 surfaces. The calculated stabilities resulting models suggest that unsupported RuS nanoparticles in HDS conditions are like a polyhedron six, eight, twelve (100), (111), (102) faces, respectively. area these faces covers about 40%, 37%, 23% total particle, atomic basins outermost individual atoms exposed surfaces were determined using quantum molecules methodology. Direct visualization has shown hole just at middle sulfur provides access uncovered metal sites. Analysis electrostatic potential mapped onto selected electron density isocontour (0.001 au) reveals very high reactivity holes toward electrodonating reagents. Consequently, attraction between sites S coming from reagent polluting makes kinds particles quite active for catalysis.