Surface Chemistry

Research directions
Model catalysts - nanoclusters on supports: Here we focus our attention on the reactivity of metal nanoparticles which are adsorbed on metal oxide supports. These topics are related to heterogeneous catalysis and materials science applications. In collaboration with national laboratories, for some of these projects, nanofabrication techniques such as electron beam lithography are used to manufacture the samples. The figure below shows a scanning electron microscopy image of a typical sample (made at Argonne National labs and Molecular Foundry in Chicago/Berkeley by S. Cabrini and L. Ocola) and molecular beam scattering data.
               

Nanotubes: We work with carbon nanotubes and inorganic nanotubes mostly towards application in heterogeneous catalysis. The figure shows a sample of WS2 nanotubes which is used for hydrodesulfurization catalysis.

Alkaline earth oxides: Projects related to a DoE-EPSCoR state grant concern the reactivity of CaO, graphite, and iron oxide surfaces and related nanoclusters. Coal includes these compounds as impurities. Therefore we study the interaction of combustion gases with these systems.

Measuring techniques
Adsorption dynamics: Application of molecular beam scattering techniques to characterize the morphology and reactivity (SAR, Structure Activity Relationship) of catalyst surfaces. A molecular beam might be compared with a LASER system, however, instead of monochromatic light we use supersonic and nearly monochromatic particle beams.
Adsorption kinetics: Temperature ramping techniques at vacuum conditions and ambient pressure (new setup under construction) are applied to characterize the kinetics of surface reactions.
Spectroscopy: We recently obtained funding to set up a laboratory x-ray photoelectron spectrometer.

Current funding (2009-2012)
                NSF-CAREER, DoE, DoE supplemental, DoE-EPSCoR

Selected Publications

Unexpected bond activation of small organic molecules on a metal oxide - butane/CaO(100), Chemical Communications (2008) 4073-4075, by E. Kadossov, U. Burghaus,

Stabilization of  polar ZnO-surfaces: Validating microscopic models by using CO as a probe molecule, Physical Review Letters 90 (2003) 106102--106102-4, by V. Staemmler, K. Fink, B. Meyer, D. Marx, M. Kunat, S.Gil Girol, U. Burghaus, Ch. Wöll.

Unexpected adsorption of oxygen on TiO2 nanotube arrays - influence of crystal structure, Nano Letters 7 (2007)1091-1094, by S. Funk, B. Hokkanen, U. Burghaus, A. Ghicov, P. Schmuki

Surface science perspective of carbon dioxide chemistry - adsorption kinetics and dynamics of CO2 on selected model surfaces, Catalysis Today, in press, (2009), by U. Burghaus

 

Recent Publications

Adsorption and reaction kinetics of small organic molecules on WS2 nanotubes: an ultra-high vacuum study, Chemical Physics Letters, 479 (2009) 109, by M. Komarneni, A. Sand, P. Nevin, A. Zak, U. Burghaus

Multi-site kinetic monte carlo simulations of thermal desorption spectroscopy data, Surface Science 603 (2009) 2494-2501, by E. Kadossov, U. Burghaus

Possible effect of carbon nanotube diameter on gas-surface interactions – the case of benzene, water, and n-pentane adsorption on SWCNTs at ultra-high vacuum conditions, Chemical Physics Letters 476 (2009) 227-231, by M. Komarneni, A. Sand, J. Goering, U. Burghaus, M. Lu, L. Veca, Ya-Ping Sun

Interaction of combustion gases with a CaO(100) surface: adsorption kinetics and dynamics, Am. Chem. Soc., Div. Fuel Chem. 54 (2009) 268, by E. Kadossov, M.R. Hoffmann, U. Burghaus

Adsorption kinetics of small organic molecules on thick and thinner layers of carbon nanotubes, Chemical Physics Letters 470 (2009) 300-303, by M. Komarneni, A. Sand, M. Lu, U. Burghaus

Adsorption  of  thiophene  on  inorganic  MoS2  fullerene-like  nanoparticles, Catalysis Letters 129 (2009) 66-70, by M. Komarneni, A. Sand, U. Burghaus

Surface science perspective of carbon dioxide chemistry - adsorption kinetics and dynamics of CO2 on selected model surfaces, Catalysis Today, in press, (2009), by U. Burghaus

 

Joint Projects

Pacific Northwest National Laboratory (PNNL): I. Lyubinetsky, L. Saraf, B.W. Arey
Argonne National Laboratory: R. Divan, L. Ocola
Brookhaven National laboratory: M. Lu
Berkeley Molecular Foundry (LBNL): S. Cabrini
Columbia University; N.Turro, B.White, S. O'Brien
NASA: G. Bozzolo, J.E. Garces (Argentina), K.W. Street, P.B. Abel
University of North Dakota (UND): M. Hoffmann, W. Seames
Erlangen-Nuernberg University (Germany): A. Ghicov, P. Schmuki
Weizmann Institute of Science (Israel):  R. Tenne 
Teaching collaborations; D. Ulness (Concordia College, MN), W. Lin, R.V. Pieri, E. Khan, C. Ulven  (NDSU)