Nitrogen-doped carbon aerogels with high surface area for supercapacitors and gas adsorption

Abstract

Doping of nitrogen atoms has been considered to be a common strategy for improving the performance of carbon aerogels. In this work, two kinds of nitrogen-doped carbon aerogels with high porosity (NCA-800 and NCA-900) are prepared through polymerization of pyrrole and formaldehyde monomers under a hypersaline condition and subsequent carbonization at different temperatures (800 and 900 °C). In the whole preparation process, zinc chloride is not only used to provide a hypersaline environment for the polymerization of pyrrole and formaldehyde, but also applied as a catalyst and an activating agent. The as-prepared aerogels possess high specific surface area values (1450 m2 g–1 for NCA-800 and 1670 m2 g–1 for NCA-900) and moderate nitrogen contents (10.86 atom% for NCA-800 and 4.09 atom% for NCA-900). As gas adsorbents, they show high uptake capacities for carbon dioxide (∼16 wt%) at 273 K under 1.0 bar on the basis of high porosity and nitrogen contents. When applied as electrodes for supercapacitors, the as-prepared aerogels exhibit good electrochemical performances.