NO2 adsorption at ambient temperature on urea-modified ordered mesoporous carbon

A soft-templated ordered mesoporous carbon was synthesized, impregnated with urea and pyrolyzed at 500 and 800 °C. The samples obtained were tested as NO2 adsorbents. Their structural properties and surface chemistry, before and after NO2 exposure, were investigated using nitrogen adsorption, TEM, potentiometric titration and thermal analysis. Results showed that the ordered mesoporous structure remains stable throughout the treatment applied and exposure to NO2. Even though the initial carbon exhibited a high NO2 adsorption capacity, the incorporation of nitrogen groups to the carbon surface, resulted in the further improvement of the performance after heat treatment. The mechanism of reactive adsorption was found to be significantly affected by surface chemistry of mesoporous carbons.