Nanoporous carbon materials obtained by sucrose carbonization in the presence of KOH

This work reports the synthesis and characterization of novel carbon materials obtained by thermal activation in the presence of KOH of a sucrose-derived char. The effect of both, the amount of KOH and of carbonization temperature, on the properties of the final materials has been investigated by means of: FE-SEM; micro-Raman spectroscopy; adsorption of: (i) N2 at 77 K; (ii) CO2 at 273 K; (iii) H2 at 77 K. It is shown that carbonization temperature does not affect much the properties of the final material, whereas the amount of KOH dictates the porosity (improving the microporous volume) and slightly affects the degree of graphitization. Adsorption of H2 at sub-atmospheric pressure showed the highest uptake (2.5% by weight) for the material with the highest microporous volume, obtained by carbonization at 900 °C with a KOH/char mass ratio of 2.0.