Synthesis of N-rich microporous carbon materials from chitosan by alkali activation using Na2CO3

•The novel manufacturing procedure of nitrogen-rich carbon materials.•The biopolymer chitosan can be activated by sodium carbonate.•The effect of the addition of activator and the temperature of carbonization was investigated.•The N-rich carbon materials exhibit high specific surface area and microporous structure.

The paper presents the first systematic study on the synthesis of nitrogen-rich nanoporous activated carbons by chitosan carbonization in the presence of a hard template (activator), i.e. Na2CO3. Carbonization process was carried out in the range of 600–900 °C under a flow of nitrogen. The effect of the addition of different volumes of activator and the temperature of carbonization on the development of specific surface area and pore structure (pore volume and median pore diameter) of the activated carbons was investigated. Additionally, the nitrogen content and nitrogen-containing surface species were determined by means of XPS and combustion elemental analysis. The nitrogen content was placed in the range of 2.4–13.1 wt.%. On the grounds of the low-temperature adsorption of nitrogen, it was found that obtained adsorption isotherms were of type-I, based on the IUPAC classification, which is typical for microporous materials.