One-step nanocasting synthesis of nitrogen and phosphorus dual heteroatom doped ordered mesoporous carbons for supercapacitor application

Nitrogen (N) and phosphorus (P) dual heteroatom doped ordered mesoporous carbon (NPOMC) is synthesized via a one-step nanocasting route. Sucrose, cyanamide and phosphoric acid were used as precursors for carbon, nitrogen and phosphorus in the preparation of NPOMC. The synthesized samples were characterized by TEM, XRD, XPS, N2 sorption analysis and electrochemical methods. The results showed that nitrogen and phosphorus were successfully incorporated into carbon network and the doping amount of nitrogen and phosphorus and the population of various functionalities were correlated with each other. The obtained NPOMC exhibited much enhanced specific capacitance (220 F g−1 at 1 A g−1), good rate capability (178 F g−1 at 16 A g−1 with capacitance retention of 81%) and an excellent cycling stability (91%) in 6 mol L−1 KOH aqueous electrolytes compared with NOMC, POMC and OMC.