Nanostructure Growth on Surfaces

Project Decription

Example photoThis project focuses on low dimensional surface structures (ultrathin metallic films, islands, wires, etc.), especially in systems exhibiting Quantum Size Effects (QSE). Since such structures are metastable and are grown far from equilibrium, it is important to identify the optimal kinetic pathways. This requires a better understanding of many atomistic processes (surface diffusion, nucleation, coarsening, etc.) that define the kinetic pathway. In addition the properties of the grown structures (electronic band structure, density-of-states, etc.) depend on the structure's dimensions, so this also opens the possibility to control their potential uses in chemical reactivity and energy storage.

Phenomena on the nanoscale can be very different from phenomena in the bulk. Either because of free bonds of atoms at the nanostructure edges, or because quantum mechanics becomes more important on the nanoscale, unexpected effects and properties emerge. One of the goals is to discover robust ways to grow surface-supported nanostructures (nanoislands, nanodots, nanowires, etc.) with controllable dimensions (height, size, shape) and morphology (flat-top, wedding cake, stepped, etc). A different goal is to use these custom-made controllable nanostructures to enhance the rate of atomistic processes (nucleation, adsorption) and the yield of chemical reactions.

Graphene(G) is an exotic material that has been studied over the last eight years for possible applications in ultrafast microelectronics, catalysis, and spintronics. Recent research in the group has focused on the growth of metals deposited on single or bi-layer G. We have observed unusual nucleation in Fe on G, 3-d growth mode for all metals (due to the higher adsorption energy vs. bulk cohesive energy of the deposited metal), and for Dy growth the FCC crystal structure differs from bulk HCP Dy. The continued research of metals on graphene will pave the way for G applications by optimizing metal contacts on G.

Group Members

  • M. C. Tringides (Group Leader)
  • M. Hupalo (Staff Scientist)
  • M. Kolmer (Scientist II)
  • S. Chen (Postdoc)
  • J. Hall (PhD Student)

Local Collaborators

  • C. Z. Wang (Ames Lab)
  • K. M. Ho (Physics)
  • P. A. Thiel (Chemistry)
  • J. W. Evans (Physics)
  • C. M. Soukoulis (Physics)
  • T. Koschny (Physics)
  • A. Kaminski (Physics)

Long-term Outside Collaborators

  • Z. Chvoj and Z. Chromcova (Institute of Physics Academy of Sciences Czech Republic)
  • M. S. Altman and M. Ka Lun Michael (Hong Kong University of Science and Technology)
  • P. Miceli (University of Missouri)
  • E. Conrad (Georgia Tech)
  • M. Jalochowski (Lublin, Poland)
  • M. Horn von Hoegen (Essen Germany)
  • E. Bauer (Arizona)
  • R. Miranda and J. de Miquel (Autonoma University of Madrid )
  • Andree Zotov (Vladivostok Russia)
  • C. Brun and D. Roditchev (Institute des Nanosciences de Paris)
  • S. Chiang (UC Davis)

Recent Graduates and Previous Members

  • S. Chen (PhD Student 2023)
  • F. Timmer (Postdoc 2018)
  • M. T. Hershberger
    (PhD Student 2017)
  • H. Hattab
    (Postdoc 2013-15, University of Essen Duisburg sponsored by the Leopoldina, the German National Academy of Sciences)
  • S. M. Binz
    (PhD Student 2012)
  • J. Chen
    (PhD Student 2009)
  • M. K. Yakes
    (PhD Student 2006)