Controllable synthesis of nitrogen-doped hollow carbon nanospheres with dopamine as precursor for CO2 capture

摘要

Nitrogen-doped hollow carbon nanospheres (N-HCSs) have been synthesized by self-polymerization of dopamine on silica spheres using the modified Stober method. The fabrication process uses dopamine as carbon and nitrogen source and tetraethyl orthosilicate as a structure-assisting agent. The particle sizes and shell thicknesses of the N-HCSs can be easily tuned in the range of 270-700 nm and 30-55 nm, respectively, by simply modifying the ethanol/water volume ratios. The surface areas of N-HCSs are in the range of 345-463 m(2) g(-1), and the total pore volumes are in the range of 0.34-0.52 cm(3) g(-1). The obtained N-HCSs have uniform mesoporous size of similar to 4.0 nm, and high nitrogen loading content of 7.2 at%. Besides, the N-HCSs exhibit a considerable performance for CO2 capture with a capacity of 3.09 mmol g(-1) at 25 degrees C and 1.0 bar and a good cycling stability.