Electric Double Layer Capacitance of Mica Template Carbon

摘要

Novel carbon structure has been prepared from heterocyclic hydrocarbons, which contain a nitrogen atom, using a fluorine expandable mica as a template. The obtained carbon particles as a residue after acid washing of carbon/mica nanocomposite comprised two structural parts: very thin film and surrounding rim part. The latter rim part has constant width of about 20nm. In addition, on account of the nitrogen atoms in the starting hydrocarbons, a certain amount (10-18wt%) of nitrogen remained in the resulting template carbon. These template carbons indicated a high electric double layer capacitance amounting to more than 100- 180F/g in H2SO4 electrolyte. Because of low surface area of the samples, specific capacitance per unit surface area could reach 1.2- 2.2F/m2, which is over ten times as high as the capacitance of ordinary activated carbons. The capacitance decreased markedly with heat treatment temperature (>1000°C) of the template carbon. Since the heat treatment accompanied the elimination of nitrogen from the sample, the presence of residual nitrogen may account for such a high capacitance.