THE SURFACE STRUCTURE OF NITROGEN-DOPED CARBON AEROGELS

摘要

Carbon aerogels were synthesized by sol-gel polymerization of phenol, melamine and formaldehyde followed by supercritical drying and pyrolysis. The chemical structure of the carbon aerogels were characterized by elemental analysis and XPS. It was found that the all of carbon aerogel samples have almost the same carbon and oxygen elemental states, as well as similar oxygen-containing groups. However, the weight fractions of nitrogen in carbon aerogels increased obviously with the ratio of melamine to phenol ratios in the range of 1.6 to 3.1 wt%. The nitrogen was enriched on surface of carbon nanoparticles with two-thirds of them on periphery of graphene layers (pyridinic-N, pyrrolic-N and/or pyridonic-N, pyridine N-oxide) and one-third of them inside graphene layers (quaternary-N).