FULLERENES FORMATION FROM AROMATIC PRECURSORS BY A SURFACE CATALYSED CYCLODEHYDROGENATION PROCESS

Controlled synthesis of fullerenes and heterofullerenes on surfaces is a preceding step towards the development of a true fullerene-based molecular electronics. New methods are required for the rational, size-controlled synthesis of fullerenes, heterofullerenes, and endohedral fullerenes that cannot be accessed by the current method of graphite vaporization. Recently, pioneering experiments have shown that C60 fullerene can be formed by flash vacuum pyrolysis of a trichlorinated precursor C60H57Cl3. However, this precursor was prepared in 11 steps from commercially available materials and the final dehydrogenation/dehydrochlorination proceeds in the gas phase in ca. 0.1-1.0 % yield1. Here we report a highly efficient (<100%) dehydrogenation mechanism leading to the formation of fullerene C60 and for the first time triazafullerene C57N3 in a one-step from their corresponding planar polycyclic aromatic precursors by a surface catalysed process2. We have visualized the whole process by in-situ Scanning Tunneling Microscopy (STM) and X-Ray Photoemission spectroscopy (XPS). The cyclodehydrogenation has been confirmed by the thermal desorption of HD and D2 from hexadeuterated 1-d6 precursors, by the mass-spectrometric detection of C60 in the platinum-catalysed dehydrogenation, and the whol