II International Symposium on Carbon for Catalysis ABSTRACTS

OP-I-27
spectroscopic feature of C1s spectra -" shake-up satellite", which indicates sp 2 -hybridization,
is expressed with unusually high intensity.
When methane is used as the reagent under the same conditions such a behavior is not
observed. We did not obtain any significant changes in C1s position of the spectra as well as
changes in the shape of the Auger spectra in this case, although the experiments were carried
out in the range of temperatures and pressure being even wider than those for ethylene.
The “high energetic films” (we refer it to the films where C1s have the position more
than 284.6 eV) being different from planar graphite films are similar in the characteristics to
nanotubes or fullerenes layers. Applying RAM we have found that these films consist of hills
and pits with diameters about hundreds of nanometers.
The carbon films obtained by hydrocarbon interaction are stable enough, but less than
planar graphite. We present systematic data concerning carbon burning by interaction with
O 2 . We have shown that the kinetic curves of the burning are very different and strongly
depend on the structure of carbon adsorbed layers. The fullerite like adsorbed layers (E b (C1s)
> 284.7 eV) are characterized by constant reaction rate in the high coverage range, while the
carbon adsorbed layers consisted of graphite islands layers (E b (C1s) < 284.4 eV) are
characterized by well known “S”-shape curve of carbon burning with high efficiency of this
process. It is noteworthy that the graphite uniform layer was inert to the O 2 under the all
studied conditions.
Under the high pressure action (> 10 Pa) of some hydrocarbons (ethylene and propane) at
temperature above 850 0 C the continuous growth of carbon films has been revealed. It was
established that in the process of the thick carbon films formation their XPS futures are
permanently altered. The obtained carbon films grown on the surface of Pt(111) can be used
as different carbon substrates for investigation of the model supported catalysts.
References
1 Boronin Andrei, Pazhetnov Egor, Koscheev Sergei. Effect of hydrocarbon nature on
carbon deposition on the surface of Pt(111). "Carbon for Catalysis" CarboCat - 2004,
Post-<strong>Symposium</strong> (after the 13th ICC in Paris) 18-20 July, 2004, Lausanne, Switzerland,
p. p 31-32.
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