Spectroscopy of Endohedrally Doped non-IPR Fullerenes M@C60 on a Substrate

• Applicant: Professor Dr. Wolfgang Eberhardt, since 4/2013
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2010 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 120401550

• Final Report Year: 2017

Final Report Abstract

Fullerene cages with less than 60 carbon atoms, so called non-IPR fullerenes, represent a special class of fullerenes with promising electronic and magnetic properties when doped by metal atoms. The molecular identity and semiconducting properties makes doped fullerene clusters very appealing to be used as materials for nanodevice development with an active area of <1 nm. So far, the exploration of non-IPR fullerenes has been hampered owing to difficulties in the isolation from a carbon soot produced by standard Huffmann-Kretschmer technique. Here we report on the principal design of a fullerene arc cluster ion source for the production and direct deposition of doped fullerenes from a cluster beam, i.e. circumventing the elaborating elution from a carbon soot. First test with lanthanumdoped carbon electrodes demonstrates the operational readiness of the source for future experiments. In parallel to the development of the fullerene cluster source we deposited small clusters on unsupported graphene pits and HOPG to do spectromicroscopy on these two-dimensional metalcarbon hybrid compounds. A comparison of the dimensionality of the carbon host, i.e. two-dimensional (graphene) versus spherical symmetry (fullerene) has been the driving force for a comparative study. Ag-cluster/graphene hybrid compounds have been synthesized and explored by X-ray spectroscopy and TEM.

Publications

• Phys. Rev. A 85, 013201 (2012)
  Stanzel, Jörg; Neeb, Matthias; Eberhardt, Wolfgang; Lisinetskaya, Polina G.; Petersen, Jens & Mitrić, Roland
  
• Size-dependent Auger spectra and two-hole Coulomb interaction of small supported Cun-clusters, Phys. Chem. Chem. Phys. 15 9575 (2013)
  Peters, S.; Peredkov, S.; Neeb, M.; Eberhardt, W. & Al-Hada, M.
  
• Size-dependent XPS spectra of small supported Aun-clusters, Surf Sci. 608, 129 (2013)
  Peters, S.; Peredkov, S.; Neeb, M.; Eberhardt, W. & Al-Hada, M.
  
• Size-dependent XPS spectra of deposited Cunclusters goverened by initial state effects, J. Electron Spectrosc. Relat. Phenom. 192, 52 (2014)
  Peters, S.; Peredkov, S.; Al-Hada, M.; Neeb, M. & Eberhardt, W.
  
• Nanoisland formation of deposited Agn-clusters on HOPG as determined by inner-shell photoionization spectroscopy, Surf. Sci., 639, 43 (2015).
  Al-Hada, M.; Peters, S.; Peredkov, S.; Neeb, M. & Eberhardt, W.
  
• Structural investigation of supported Cun-clusters under vacuum and ambient air conditions using EXAFS spectroscopy, Catal. Sci. Technol. 6, 6942 (2016)
  Peredkov, S.; Peters, S.; Al-Hada, M.; Erko, A.; Neeb, M. & Eberhardt, W.
  
• Nanoparticle formation of deposited Agn-clusters on free-standing graphene, Surf. Sci., 665, 108 (2017)
  Al-Hada, M.; Peters, S.; Gregoratti, L.; Amati, M.; Sezen, H.; Parisse, P.; Selve, S.; Niermann, T.; Berger, D.; Neeb, M. & Eberhardt, W.