Desulfurization of Thiophene on Au/TiC(001): Au−C Interactions and Charge Polarization

Journal Article · Thu Jan 01 00:00:00 EST 2009 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja901522a· OSTI ID:980138

Rodriguez, J; Liu, P; Takahashi, Y; Nakamura, K; Vines, F; Illas, F

Photoemission and first-principles DF calculations were used to study the interaction of thiophene with TiC(001) and Au/TiC(001) surfaces. The adsorption strength of thiophene on TiC(001) is weak, and the molecule desorbs at temperatures below 200 K. The molecule binds to Ti centers of TiC(001) through its sulfur atom with negligible structural perturbations. In spite of the very poor desulfurization performance of TiC(001) or Au(111), a Au/TiC(001) system displays a hydrodesulfurization activity higher than that of conventional Ni/MoS{sub x} catalysts. The Au?TiC(001) interactions induce a polarization of electron density around Au which substantially increases the chemical reactivity of this metal. Au nanoparticles drastically increase the hydrodesulfurization activity of TiC(001) by enhancing the bonding energy of thiophene and by helping in the dissociation of H{sub 2} to produce the hydrogen necessary for the hydrogenolysis of C-S bonds and the removal of sulfur. H{sub 2} spontaneously dissociates on small two-dimensional clusters of gold in contact with TiC(001). On these systems, the adsorption energy of thiophene is 0.45-0.65 eV larger than that on TiC(001) or Au(111). Thiophene binds in a ?5 configuration with a large elongation ({approx}0.2 {angstrom}) of the C-S bonds.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: DE-AC02-98CH10886
• OSTI ID: 980138
• Report Number(s): BNL-93056-2010-JA; JACSAT; TRN: US201015%%1523
• Journal Information: Journal of the American Chemical Society, Vol. 131, Issue 24; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
36 MATERIALS SCIENCE
ADSORPTION
ATOMS
BONDING
CATALYSTS
CONFIGURATION
DENSITY FUNCTIONAL METHOD
DESULFURIZATION
DISSOCIATION
DISTURBANCES
ELECTRON DENSITY
ELONGATION
ENERGY
GOLD
HYDROGEN
INTERACTIONS
MOLECULES
PERFORMANCE
PHOTOEMISSION
POLARIZATION
REACTIVITY
REMOVAL
SULFUR
SURFACES
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
THIOPHENE
national synchrotron light source