Resumo

MORENO, Astrid R.; BRICENO, Nelson O.  e  DIAZ, José de J.. MODIFICATION OF THE CHEMISTRY SURFACE CHARACTERISTICS OF CARBON AEROGELS BY OXIDATIVE TREATMENTS. Rev.Colomb.Quim. [online]. 2010, vol.39, n.2, pp.257-267. ISSN 0120-2804.

Carbon aerogels were prepared by carbonization of organic gels synthesized by the sol-gel methodology from resorcinol, formaldehyde and a basic catalyst. Its surface was modified by treatments with oxygen (8.8% in N₂) and nitric acid. The materials were characterized by nitrogen adsorption isotherms at 77 K, temperature programmed decomposition of CO and CO₂ (TPD), zero charge point and isoeletric point. It was found that the modified aerogels have a well developed micro and mesoporosity; the TPD results shows that oxidative treatment with oxygen increase the concentration of hydroxyl and carbonyl groups on the surface of aerogels, whereas the oxidation with nitric acid increase the concentration of carboxyl groups.

Palavras-chave : carbon aerogels; oxidative treatments; surface chemistry.