AVS 66th International Symposium & Exhibition
    Thin Films Division Tuesday Sessions
       Session TF+PS-TuA

Paper TF+PS-TuA10
Epitaxial Growth of Ultrathin Molybedenum Nitrides on Ru(0001) and Ag(100)

Tuesday, October 22, 2019, 5:20 pm, Room A124-125

Session: Epitaxial Thin Films
Presenter: Asim Khaniya, University of Central Florida
Authors: A. Khaniya, University of Central Florida
M. Sajid, University of Central Florida
A. Kara, University of Central Florida
W.E. Kaden, University of Central Florida
Correspondent: Click to Email
Molybdenum-nitrides are known to possess interesting mechanical, electronic, and catalytic properties. For example, (i) hexagonal δ-MoN exhibits mechanical elasticity and hardness values comparable to cubic BN and diamond, (ii) both hexaganol and cubic phases of molybdeumn nitrides are known to be superconducting, and (iii) mixed-phase structures have been shown to outperform commercial hydrotreatment catalysts for selective nitrogen removal from heterocyclic organic feedstocks. To better understand these properties, many groups have worked to create improved recipes to grow different phase-pure crystallographic phases of the material. To-date, the most successful procedures have leveraged epitaxy to improve long-range bulk order, but have lacked the well-defined, planar terminations suitable for controlled surface-science investigations. To establish such samples, our group has opted to use low energy nitrogen ions in tandem with molybdenum physical vapor deposition to grow and characterize molybdenum-nitride films on Ru(0001) and Ag(100) supports, which have been chosen to template the growth of hexaganol and cubic phases of the nitride. At the time of this abstract submission, we have succeeded in the growth of a δ-MoN-like film that appears to grow layer-by-layer and in registry with the Ru(0001) support, and are now in the early stages of repeating the process to create γ-Mo2N on Ag via an analogous process. This talk will focus on the interesting aspects of these materials (particularly those relevant to catalysis), our approach to film preparation, and a thorough analysis of the physical properties of the resultant films and growth modes via: XPS, LEED, He+ Ion Scattering Spectroscopy, STM, and DFT.