II International Symposium on Carbon for Catalysis ABSTRACTS

PP-<strong>II</strong>-8
POROUS CARBONS/ZnO COMPOSITES: SYNTHESIS AND CHARACTERIZATION
Cesano F., Scarano D., Bertarione S., Bonino F., Damin A., Bordiga S., Prestipino C.,
Lamberti C., Zecchina A.
Department of Inorganic, Physical and Materials Chemistry, NIS (Nanostructured Interfaces
and Surfaces) Centre of Excellence, University of Torino, Via P. Giuria 7, I-10125 Torino, Italy
e-mail: federico.cesano@unito.it
Porous carbons have attracted a great attention in recent years, due to their potential
applications in many fields, including catalytic supports, gas storage, molecular sieves, porous
electrodes [1]. Organic polymers like as polyacrylonitrile (PAN), phenolic resin, polyimides,
poly(p-phenylene vinylene), polyvinyl acetate and polyfurfuryl alcohol (PFA) are commonly
used as carbonaceous precursors [2]. Among them, PFA can be easy prepared from a solution
of furfuryl alcohol and organic (p-toluenesulphonic, trifluoroacetic) or inorganic (SnCl 4 , I 2 )
Brønsted/Lewis acid catalysts [3]. The pyrolysis process of PFA is expected to form nongraphitizing
carbons (char formers) with a relatively high carbon yield if compared to other
precursors [4,5].
In this contribution it is shown that, starting from furfuryl alcohol and ZnCl 2 (Lewis acid
catalyst), PFA has been obtained under mild conditions (80-100°C). Subsequent pyrolysis at
500-600°C under controlled atmosphere (N 2 /air mixture) gives rise to a highly homogeneous
and porous ZnO/carbon composite (Fig.1 a,c), which after a subsequent thermal treatment at
higher temperatures in N 2 (800-900 °C) changes into a porous carbon (Fig.1 b,d). The carbon
surface is now characterized by a clear presence of pockets. We think that these pockets are
the places where ZnO microcrystals were implanted. In other words, ZnO has behaved as a
template of the carbon surface.
The formation of an oxide/carbon nanocomposite is very interesting, because it is expected: to
improve the abrasion resistance, modify the electrical properties, act as flame retardant and
UV stabilizer of the carbon phase. A second element of interest in this novel syntesis route of
carbon/ZnO composites, via catalytic dehydroxylation and dehydrogenation, is represented by
the presence of ZnO structures with photocatalytic properties for sensing properties. A further
element of interest is represented by the formation of an imprinted surface carbon phase,
which is originated by reduction of the ZnO microcrystallites implanted on the carbon surface
and successive vaporization of metallic Zn.
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