Paper SS-TuP1
Size-Selected Deposition of Mo₆S₈⁺ on Au(111)

Tuesday, October 16, 2007, 6:00 pm, Room 4C

Nanoscale MoS₂ has a layered assembly that shows a high propensity towards folding, forming hollow nanotube and fullerene structures which display a wide range of catalytic, photovoltaic, and lubricant properties.^1-3 Supported MoS₂ nanoparticles are known for their ability to catalyze a wide array of heterogenous reactions, in particular hydrodesulfurization (HDS).^4-5 However, understanding the role of size, structure, and overall composition of the MoS₂ particles in HDS has not yet been resolved due to the inhomogeneity of these commercial catalysts. Work done in our laboratory is geared towards preparing homogenous samples in ultra high vacuum (UHV) that can serve as model systems for these types of catalytic reactions. We are currently investigating the reactivity of size-selected transition metal clusters generated in the gas-phase and deposited on a Au(111) surface. Using a magnetron cluster source, we are able to produce a wide range of nanoparticle stoichiometries including the metal sulfide core of the superconducting Chevrel phase⁶, Mo₆S₈⁺. The work presented here focuses on characterization of the Mo₆S₈⁺ cluster deposited on a Au(111) single crystal using surface science techniques such as TPD, AES, XPS, and UPS.

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