Synthesis, characterization and dye removal capacities of N-doped mesoporous carbons

Nitrogen-doped ordered mesoporous carbons were synthesized by chemical vapor deposition, using acetonitrile as carbon and nitrogen source and SBA-15 as mesoporous silica template. Their porous texture, structural order and surface chemistry were studied as a function of the experimental conditions (acetonitrile stream concentration and deposition time). A non-doped ordered mesoporous carbon was also prepared by the same procedure using propylene as carbon source. Methylene blue, methyl orange and fuchsin acid were selected as probe molecules to investigate the dye adsorption behavior on the ordered mesoporous carbons. Both N-doped and non-doped ordered mesoporous carbons adsorbed large amounts of these three dyes demonstrating the importance of mesoporosity, especially for the adsorption of larger dyes (e.g. fuchsin acid). The presence of nitrogen functional groups was detrimental for the adsorption of the basic dye (methylene blue). On the other hand, the nitrogen functionalities improved the adsorption kinetics for both acid and basic dyes, and the N-doped samples achieved 100% of their maximum adsorption capacities in less than 15 min.