Synthesis and textural characteristics of organic aerogels, transition-metal-containing organic aerogels and their carbonized derivatives
نویسنده
چکیده
Four organic aerogels were prepared by the sol-gel method from polymerization of resorcinol with formaldehyde catalyzed by Na CO . These aerogels were further pyrolyzed in N in order to obtain their corresponding carbon aerogels, 2 3 2 and after that activated with either steam or CO to obtain activated carbon aerogels. Another series of organic aerogels and 2 their pyrolyzed and activated derivatives were prepared without a catalyst or in the presence of Ag, Pd or Pt. All these samples were texturally characterized, which has shown the porous modifications undergone by the aerogels during the pyrolysis and activation processes. The textural characteristics of the transition-metal-containing activated carbon aerogels depend on the nature of the metal. Thus, whereas the sample containing Pt, in a very small amount, had the largest meso and 3 21 macropore volume (0.822 and 2.982 cm g ) found, those containing either Pd or Ag were essentially microporous. 1999 Elsevier Science Ltd. All rights reserved.
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