Dr. Roland Widmer

Deputy Group Leader Functional Surfaces

Roland Widmer received his Ph.D. in Physical Chemistry in 2002 from the University of Bern (Switzerland) on in-situ electrolytic scanning probe investigations of adsorbate processes on metallic substrates. He joined the nanotech@surfaces Laboratory of Empa in 2003 and did a sabbatical in the group of Prof. K. Horn at the Fritz-Haber-Institute (Berlin) in 2008. The incentive of his research covers a wide range of topics at the interface of materials science, surface physics and chemistry, with the aim of the fabrication and understanding of complex surfaces in terms of atomic and electronic structure as well as the understanding of their reactivity on the molecular and atomic level. To gain an understanding of these fundamental physical and chemical properties, he follows an experimental approach building on state-of-the-art scanning probe methods (UHV temperature-controlled STM/STS, electrochemical STM) combined with structural and spectroscopic methods based on photoelectron emission techniques (XPS, UPS, XPD, ARPES).
Currently, the catalytic activity and the interplay with molecules attracted his research interests as fundamental issues are largely unknown and it represents a strongly interdisciplinary field of research. In this context, the structural and electronic investigations of intermetallic compounds such as quasicrystals and approximants, but also catalytic active materials such as PdGa are highly relevant. Through the atomic and electronic structure determination, identification of initial adsorption sites and reaction mechanisms on different single crystal surfaces, he contributed substantially to the knowledge of the functionality of PdGa as catalyst. Roland Widmer supervised several PhD and Master Theses and presented his work at international conferences also as invited speaker. He has published more than 50 papers in international journals.

Fields of interest

Surface Physics and Chemistry; Chirality and Enantioselectivity; On-surface chemical reactions; Catalytic processes; Intermetallic Compounds; Complex surface structures

Selected publications

J. Prinz, O. Gröning, H. Brune, R. Widmer, Highly Enantioselective Adsorption of Small Prochiral Molecules on a Chiral Intermetallic Compound, Angewandte Chemie – Int. Ed. 54, 3902 (2015). DOI: 10.1002/ange.201410107

V.A. Rogalev, O. Gröning, R. Widmer, J.H. Dil, F. Bisti, L.L. Lev, T. Schmitt, V.N. Strocov, Fermi states and anisotropy of Brillouin zone scattering in the decagonal Al-Ni-Co quasicrystal, Nat. Comm. 6, 8607 (2015). DOI: 10.1038/ncomms9607

R. Mäder, R.Widmer, P. Gröning, W. Steurer, O. Gröning, Correlating scanning tunneling spectroscopy with the electrical resistivity of Al-based quasicrystals and approximants, Physical Review B 87, 075425 (2013). DOI: 10.1103/PhysRevB.87.075425

J. Prinz, R. Gaspari, C.A. Pignedoli, J. Vogt, P. Gille, M. Armbrüster, H. Brune, O. Gröning, D. Passerone, R. Widmer, Isolated Pd Sites on the Intermetallic PdGa(111) and PdGa(-1-1-1) Model Catalyst Surfaces, Angewandte Chemie – International Edition 51, 9339 (2012). DOI: 10.1002/ange.201203787

R. Widmer, D. Passerone, T. Mattle, H. Sachdev, O. Gröning, Probing the selectivity of a nanostructured surface by Xenon adsorption, Nanoscale 4, 502 (2010). DOI: 10.1039/b9nr00431a

For a complete list of publications since 2003, please click here.