Engineering of rich nitrogen-doped and magnetic mesoporous carbon nanospheres with predictable size uniformity for acid dye molecules adsorption

The fabrication of monodispersed N-doped mesoporous carbon nanospheres (NMCNs) with a high N content remains a formidable challenge due to the decomposition of N-containing frameworks during the pyrolysis and the weak self-assembly ability between carbon precursors and templates. Herein, we demonstrated a strong hydrogen-bonding interaction driving self-assembly method to fabricate uniform NMCNs with rich N content. In this route, phloroglucinol-formaldehyde (PF) not only acted as a rigid phenolic resin framework to prevent N-containing framework from decompose during carbonization, but also provided greater driving force for the self-assembly interaction with F127 through enhanced hydrogen-bonding interaction. The nitrogen doping level, particle size and uniformity of the formed NMCNs could be facilely tuned by adjusting the concentrations of ethylenediamine (EDA). Interestingly, the NMCNs possess high N content (up to similar to 13.2 wt%), high surface area (556 m(2) g(-1)) and large pore volumes (similar to 0.50 cm(3)/g). By engineering the compositional diversity inside the single nanoparticles, Fe3O4 nanoparticles can be introduced into the NMCNs. The resultant Fe-NMCNs showed efficient adsorption (283 mg g(-1)) and magnetic separation property for acid red 57. The feasibility of the fabrication strategy may provide a new insight into the understanding of preparing functionalized carbon nanomaterials with mesoporous structure.